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Coolant fan override switch - Printable Version +- Wanderlodge Gurus - The Member Funded Wanderlodge Forum (http://www.wanderlodgegurus.com) +-- Forum: Yahoo Groups Archive (/forumdisplay.php?fid=61) +--- Forum: WanderlodgeForum (/forumdisplay.php?fid=63) +--- Thread: Coolant fan override switch (/showthread.php?tid=4363) Pages: 1 2 |
Coolant fan override switch - David Brady - 02-19-2007 15:12 Got it. Thanks everyone, I really appreciate your help. I got some testing to do, but it's going to have to wait a few days. David B '02 LXi, Smokey NC Gregory OConnor wrote: > David, Bypass and override are two independent features. I believe > bypass is a safety feature for a clogged hydro oil filter. Bypass is > not triggered by the override dash switch > GregoryO'Connor > 94ptRomolandCa > > --- In WanderlodgeForum@yahoogroups.com, David Brady > wrote: > >> Hi Rich, >> >> Thanks for the help. When I return to the bus I'll try your test. >> I guess if the fan speed increases, then the problem is between >> the dash switch and the "bypass valve". Alas, no wiring schematics.. >> I'll let you know what happens. >> >> >> David B >> '02 LXi, Smokey >> NC >> >> g_man1146 wrote: >> >>> Hi David, >>> >>> AS others have stated, a fan over-ride failure should fault to >>> > high > >>> speed. If you are not getting high fan speed with the air >>> > conditioner > >>> on or with the switch set to "over-ride" locate (assuming Detroit >>> > S60) > >>> a connector plug at the rear of the engine compartment (closest >>> > to rear > >>> bumper) on the fan side. You should see a hydraulic hose from the >>> > fan > >>> motor to this block (bypass valve) and wires coming from it. If >>> > you > >>> disconnect the connector plug on these wires, the fan should come >>> > up to > >>> full RPM. (ROAR) If it increases but not fully, the problem may >>> > lie > >>> with the hydraulic pump which is attached to the PTO on the curb >>> > side > >>> of the Allison or with the hydraulic bypass valve. BB makes >>> > changes all > >>> the time and my coach (3 years older) may not be set up the same. >>> > If > >>> you are not overheating on long hills everything may be normal. I >>> experienced an overheating situation only in extreme situations >>> > and > >>> determined the problem to be a faulty hydraulic pump supplied as >>> > part > >>> of the PTO recall from BB. The pump did not have sufficient >>> > capacity to > >>> run the fan at full speed. They supplied a new pump and labor to >>> install. The fan motor is actually rated at about 40 HP at full >>> capacity. No wonder it is designed to cut back when not needed! >>> >>> Rich D. '99LXi43' CT >>> >>> --- In WanderlodgeForum@yahoogroups.com, David Brady >>> > wrote: > >>> >>> >>>> Folks, >>>> >>>> On my '02 LXi, with the engine at idle, the fan seems to rotate >>>> at 400 rpm or so (give or take, lol), when I enable the override >>>> switch there doesn't seem to be any change in fan speed. Should >>>> there be? or are there other parameters at work hear; i.e., >>>> > engine > >>>> temp, etc. What are the common failure modes of the fan override? >>>> >>>> Thanks, >>>> David Brady >>>> '02 LXi, Smokey >>>> NC >>>> >>>> >>>> >>> >>> >>> >>> Yahoo! Groups Links >>> >>> >>> >>> >>> >>> >>> >> >> [Non-text portions of this message have been removed] >> >> > > > > > > Yahoo! Groups Links > > > > > > [Non-text portions of this message have been removed] Coolant fan override switch - Leroy Eckert - 02-19-2007 15:14 Thanks Ron: When I started having creeping heat I could not figure it out. I changed the Alarmstat and it stopped. Apparantly, the sensor did not fail totally but was intermittant, causing the fan to act weird. After I changed it to the factory value, 195 degrees, I did not like the average water temperature. So I ordered a 190 degree and I like the results of it much better. The problem is you cannot test the sensor while sitting still, and you cannot hear the fan while driving. You can only see the result on the temperature guage with the override off and the a/c off. It makes it difficult to troubleshoot. Leroy Eckert 1990 WB-40"Smoke N Mirrors" Niceville, FL ----- Original Message ----- From: ronmarabito2002 To: WanderlodgeForum@yahoogroups.com Sent: Monday, February 19, 2007 7:46 PM Subject: [WanderlodgeForum] Re: Coolant fan override switch I have not had a alarmstat failure on my 92, but I did on my 83PT40. It definitely failed into high speed fan mode. R.E. (Ron) Marabito, Dallas, TX 92WB40 --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > This is exactly how my system works. I would think yours is similar. > 1.With the fan override off and chassis a/c off the fan will spool between approx 400x600 RPM. This continues until the temperature reaches 195 degrees, (190 degrees now in my coach) then an alarmstat turns the fan to high speed approx. 1800 RPM. The alarmstat operates in an 8 to10 degree range, therefore cycling the fan from idle to high mode over and over again, hence the cycling you may see on the engine water temperature gauge. ( you will not see the cycling with the chassis a/c on.) you may not see cycling in this configuration in hot temperatures or while climbing hills. > > 2. Fan override off, and chassis a/c on: When the chassis a/c switch is turned on( either pilot or co-pilot) the fan goes into high mode, stays in high mode until the a/c switch is turned off. This takes the fan override and the alarmstat out of the system, and provides additional continuous cooling air for the condenser. My condenser covers the top half of the radiator. Earlier models a/c condenser are on the roof, cooled by electric fans. > > 3. Fan override on, chassis a/c off. Operates the same as item 2. except the fan override switch has now taken the Alarmstat out of the system. Using this switch in winter in my coach holds the engine water temperature at engine thermostat value approx. 170-175. I expect to see continuous 190 or less in summer in this configuration. > > 4. When my alarmstat failed/or became intermittent I experienced creeping heat. I'm told that alarmstat failure is suppose to default to fan high mode. I have not verified that. > > 4. So you see, Bluebirds engineers forced our coaches to run on the high side of the DD specified range ( 170-210max, alarmed at 215 degrees: Ref: 13.12 DD Service Manual Pg. 13-48) by specifying the 195 degree alarmstat. Presumably, the thinking is that high fan RPM robs power so the higher you run the temperature the less fan activity. Unfortunately, that simply isn't the case because once the 195 degree temperature is attained the fan cycles continuously anyway. It does the same thing in my bus using a 190 degree alarmstat , however, the benefit of the lower water temperature is lower engine oil, tranny and retarder temperatures. > > When it gets hot, I intend to use my VMSpc to evaluate the temperature differences resulting from my alarmstat value change from 195 degree to 190 degree. I fully expect to see a 6-8 percent reduction in drivetrain component temperatures. > > The foregoing post has been documented with temperature values, estimated outside air temps and road conditions while driving my 1990 WB-40 over the past 5 months. > > Leroy Eckert > 1990 WB-40 > "Smoke N Mirrors" > > > > > > > ----- Original Message ----- > From: David Brady > To: WanderlodgeForum@yahoogroups.com > Sent: Sunday, February 18, 2007 10:36 PM > Subject: [WanderlodgeForum] Coolant fan override switch > > > Folks, > > On my '02 LXi, with the engine at idle, the fan seems to rotate > at 400 rpm or so (give or take, lol), when I enable the override > switch there doesn't seem to be any change in fan speed. Should > there be? or are there other parameters at work hear; i.e., engine > temp, etc. What are the common failure modes of the fan override? > > Thanks, > David Brady > '02 LXi, Smokey > NC > > > > > [Non-text portions of this message have been removed] > [Non-text portions of this message have been removed] Coolant fan override switch - Leroy Eckert - 02-19-2007 15:35 That was to Greg, but I think we are all speaking of the same thing, just a different component in the system with a bypass. The fan control valve has a bypass as does the Parker filter. The override sends a message so to speak to the valve to stop the bypass and get into high mode. So does the chassis a/c on switch. If the valve is bad, the fan will not spool up. Leroy Eckert 1990 WB-40"smoke N Mirrors" Niceville, FL ----- Original Message ----- From: g_man1146 To: WanderlodgeForum@yahoogroups.com Sent: Monday, February 19, 2007 9:08 PM Subject: [WanderlodgeForum] Re: Coolant fan override switch Gregory, On the later model Series 60's the fan bypass valve diverts hydraulic oil around the fan motor to allow the fan to run at a lower speed by sending the oil back without going through the fan "motor". If the bypass valve fails, you get full RPM of the fan as all of the oil is directed to the fan motor. This has nothing to do with a filter bypass. The bypass valve can also be tested by plugging the return line that goes to the bypass valve thus forcing all oil through the fan motor. Rich D. '99LXi43' CT --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > Yes. > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Nicevile, FL > > > ----- Original Message ----- > From: Gregory OConnor > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 8:02 PM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > David, Bypass and override are two independent features. I believe > bypass is a safety feature for a clogged hydro oil filter. Bypass is > not triggered by the override dash switch > GregoryO'Connor > 94ptRomolandCa > > --- In WanderlodgeForum@yahoogroups.com, David Brady > wrote: > > > > Hi Rich, > > > > Thanks for the help. When I return to the bus I'll try your test. > > I guess if the fan speed increases, then the problem is between > > the dash switch and the "bypass valve". Alas, no wiring schematics.. > > I'll let you know what happens. > > > > > > David B > > '02 LXi, Smokey > > NC > > > > g_man1146 wrote: > > > Hi David, > > > > > > AS others have stated, a fan over-ride failure should fault to > high > > > speed. If you are not getting high fan speed with the air > conditioner > > > on or with the switch set to "over-ride" locate (assuming Detroit > S60) > > > a connector plug at the rear of the engine compartment (closest > to rear > > > bumper) on the fan side. You should see a hydraulic hose from the > fan > > > motor to this block (bypass valve) and wires coming from it. If > you > > > disconnect the connector plug on these wires, the fan should come > up to > > > full RPM. (ROAR) If it increases but not fully, the problem may > lie > > > with the hydraulic pump which is attached to the PTO on the curb > side > > > of the Allison or with the hydraulic bypass valve. BB makes > changes all > > > the time and my coach (3 years older) may not be set up the same. > If > > > you are not overheating on long hills everything may be normal. I > > > experienced an overheating situation only in extreme situations > and > > > determined the problem to be a faulty hydraulic pump supplied as > part > > > of the PTO recall from BB. The pump did not have sufficient > capacity to > > > run the fan at full speed. They supplied a new pump and labor to > > > install. The fan motor is actually rated at about 40 HP at full > > > capacity. No wonder it is designed to cut back when not needed! > > > > > > Rich D. '99LXi43' CT > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > wrote: > > > > > >> Folks, > > >> > > >> On my '02 LXi, with the engine at idle, the fan seems to rotate > > >> at 400 rpm or so (give or take, lol), when I enable the override > > >> switch there doesn't seem to be any change in fan speed. Should > > >> there be? or are there other parameters at work hear; i.e., > engine > > >> temp, etc. What are the common failure modes of the fan override? > > >> > > >> Thanks, > > >> David Brady > > >> '02 LXi, Smokey > > >> NC > > >> > > >> > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > [Non-text portions of this message have been removed] > [Non-text portions of this message have been removed] Coolant fan override switch - Leroy Eckert - 02-19-2007 16:02 Rich: I have a question on the bypass valve if you know. I do not have a drawing of the valve. As I understand the system, the fan is normally in idle(bypass) mode until one of three things happen. The alarmstat activates high mode based on water temperature, the fan override(manually by humans or grandkids) activates high mode or the chassis a/c on switch activates high mode. Does the fan bypass valve default to fan high mode? . That would make sense otherwise the system would overheat with valve or electrical failure. If so, one could conclude that the piston in the valve is actuated by continuous power in the bypass position and the fan override, a/c switch and alarmstat cuts power off to it and it is spring loaded to full fan mode. If you know. Thanks. Trying to learn more here. Leroy Eckert 1990 WB-40"Smoke N Mirrors" Niceville,FL ----- Original Message ----- From: Leroy Eckert To: WanderlodgeForum@yahoogroups.com Sent: Monday, February 19, 2007 9:35 PM Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch That was to Greg, but I think we are all speaking of the same thing, just a different component in the system with a bypass. The fan control valve has a bypass as does the Parker filter. The override sends a message so to speak to the valve to stop the bypass and get into high mode. So does the chassis a/c on switch. If the valve is bad, the fan will not spool up. Leroy Eckert 1990 WB-40"smoke N Mirrors" Niceville, FL ----- Original Message ----- From: g_man1146 To: WanderlodgeForum@yahoogroups.com Sent: Monday, February 19, 2007 9:08 PM Subject: [WanderlodgeForum] Re: Coolant fan override switch Gregory, On the later model Series 60's the fan bypass valve diverts hydraulic oil around the fan motor to allow the fan to run at a lower speed by sending the oil back without going through the fan "motor". If the bypass valve fails, you get full RPM of the fan as all of the oil is directed to the fan motor. This has nothing to do with a filter bypass. The bypass valve can also be tested by plugging the return line that goes to the bypass valve thus forcing all oil through the fan motor. Rich D. '99LXi43' CT --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > Yes. > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Nicevile, FL > > > ----- Original Message ----- > From: Gregory OConnor > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 8:02 PM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > David, Bypass and override are two independent features. I believe > bypass is a safety feature for a clogged hydro oil filter. Bypass is > not triggered by the override dash switch > GregoryO'Connor > 94ptRomolandCa > > --- In WanderlodgeForum@yahoogroups.com, David Brady > wrote: > > > > Hi Rich, > > > > Thanks for the help. When I return to the bus I'll try your test. > > I guess if the fan speed increases, then the problem is between > > the dash switch and the "bypass valve". Alas, no wiring schematics.. > > I'll let you know what happens. > > > > > > David B > > '02 LXi, Smokey > > NC > > > > g_man1146 wrote: > > > Hi David, > > > > > > AS others have stated, a fan over-ride failure should fault to > high > > > speed. If you are not getting high fan speed with the air > conditioner > > > on or with the switch set to "over-ride" locate (assuming Detroit > S60) > > > a connector plug at the rear of the engine compartment (closest > to rear > > > bumper) on the fan side. You should see a hydraulic hose from the > fan > > > motor to this block (bypass valve) and wires coming from it. If > you > > > disconnect the connector plug on these wires, the fan should come > up to > > > full RPM. (ROAR) If it increases but not fully, the problem may > lie > > > with the hydraulic pump which is attached to the PTO on the curb > side > > > of the Allison or with the hydraulic bypass valve. BB makes > changes all > > > the time and my coach (3 years older) may not be set up the same. > If > > > you are not overheating on long hills everything may be normal. I > > > experienced an overheating situation only in extreme situations > and > > > determined the problem to be a faulty hydraulic pump supplied as > part > > > of the PTO recall from BB. The pump did not have sufficient > capacity to > > > run the fan at full speed. They supplied a new pump and labor to > > > install. The fan motor is actually rated at about 40 HP at full > > > capacity. No wonder it is designed to cut back when not needed! > > > > > > Rich D. '99LXi43' CT > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > wrote: > > > > > >> Folks, > > >> > > >> On my '02 LXi, with the engine at idle, the fan seems to rotate > > >> at 400 rpm or so (give or take, lol), when I enable the override > > >> switch there doesn't seem to be any change in fan speed. Should > > >> there be? or are there other parameters at work hear; i.e., > engine > > >> temp, etc. What are the common failure modes of the fan override? > > >> > > >> Thanks, > > >> David Brady > > >> '02 LXi, Smokey > > >> NC > > >> > > >> > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > [Non-text portions of this message have been removed] > [Non-text portions of this message have been removed] [Non-text portions of this message have been removed] Coolant fan override switch - Gregory OConnor - 02-20-2007 02:53 Ok,Is the fan pump on the S60 also the Powersteering pump. Is there a filter by pass? GregoryO'Connor 94ptRomolandCa --- In WanderlodgeForum@yahoogroups.com, "g_man1146" wrote: > > Gregory, > > On the later model Series 60's the fan bypass valve diverts > hydraulic oil around the fan motor to allow the fan to run at a > lower speed by sending the oil back without going through the > fan "motor". If the bypass valve fails, you get full RPM of the fan > as all of the oil is directed to the fan motor. This has nothing to > do with a filter bypass. The bypass valve can also be tested by > plugging the return line that goes to the bypass valve thus forcing > all oil through the fan motor. > > Rich D. '99LXi43' CT > > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > Yes. > > > > Leroy Eckert > > 1990 WB-40"Smoke N Mirrors" > > Nicevile, FL > > > > > > ----- Original Message ----- > > From: Gregory OConnor > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 8:02 PM > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > David, Bypass and override are two independent features. I > believe > > bypass is a safety feature for a clogged hydro oil filter. > Bypass is > > not triggered by the override dash switch > > GregoryO'Connor > > 94ptRomolandCa > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > wrote: > > > > > > Hi Rich, > > > > > > Thanks for the help. When I return to the bus I'll try your > test. > > > I guess if the fan speed increases, then the problem is between > > > the dash switch and the "bypass valve". Alas, no wiring > schematics.. > > > I'll let you know what happens. > > > > > > > > > David B > > > '02 LXi, Smokey > > > NC > > > > > > g_man1146 wrote: > > > > Hi David, > > > > > > > > AS others have stated, a fan over-ride failure should fault > to > > high > > > > speed. If you are not getting high fan speed with the air > > conditioner > > > > on or with the switch set to "over-ride" locate (assuming > Detroit > > S60) > > > > a connector plug at the rear of the engine compartment > (closest > > to rear > > > > bumper) on the fan side. You should see a hydraulic hose > from the > > fan > > > > motor to this block (bypass valve) and wires coming from it. > If > > you > > > > disconnect the connector plug on these wires, the fan should > come > > up to > > > > full RPM. (ROAR) If it increases but not fully, the problem > may > > lie > > > > with the hydraulic pump which is attached to the PTO on the > curb > > side > > > > of the Allison or with the hydraulic bypass valve. BB makes > > changes all > > > > the time and my coach (3 years older) may not be set up the > same. > > If > > > > you are not overheating on long hills everything may be > normal. I > > > > experienced an overheating situation only in extreme > situations > > and > > > > determined the problem to be a faulty hydraulic pump > supplied as > > part > > > > of the PTO recall from BB. The pump did not have sufficient > > capacity to > > > > run the fan at full speed. They supplied a new pump and > labor to > > > > install. The fan motor is actually rated at about 40 HP at > full > > > > capacity. No wonder it is designed to cut back when not > needed! > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > >> Folks, > > > >> > > > >> On my '02 LXi, with the engine at idle, the fan seems to > rotate > > > >> at 400 rpm or so (give or take, lol), when I enable the > override > > > >> switch there doesn't seem to be any change in fan speed. > Should > > > >> there be? or are there other parameters at work hear; i.e., > > engine > > > >> temp, etc. What are the common failure modes of the fan > override? > > > >> > > > >> Thanks, > > > >> David Brady > > > >> '02 LXi, Smokey > > > >> NC > > > >> > > > >> > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > Coolant fan override switch - g_man1146 - 02-20-2007 03:02 The pump is attached to a PTO on the curb side of the transmission and the only lines I see go to the fan. No filter bypass on mine. This setup is quite different than that on my previous '90 PT40 8V92. Rich D. '99LXi43' CT --- In WanderlodgeForum@yahoogroups.com, "Gregory OConnor" > > Ok,Is the fan pump on the S60 also the Powersteering pump. Is there a > filter by pass? > GregoryO'Connor > 94ptRomolandCa > > --- In WanderlodgeForum@yahoogroups.com, "g_man1146" > wrote: > > > > Gregory, > > > > On the later model Series 60's the fan bypass valve diverts > > hydraulic oil around the fan motor to allow the fan to run at a > > lower speed by sending the oil back without going through the > > fan "motor". If the bypass valve fails, you get full RPM of the fan > > as all of the oil is directed to the fan motor. This has nothing to > > do with a filter bypass. The bypass valve can also be tested by > > plugging the return line that goes to the bypass valve thus forcing > > all oil through the fan motor. > > > > Rich D. '99LXi43' CT > > > > > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > > > > Yes. > > > > > > Leroy Eckert > > > 1990 WB-40"Smoke N Mirrors" > > > Nicevile, FL > > > > > > > > > ----- Original Message ----- > > > From: Gregory OConnor > > > To: WanderlodgeForum@yahoogroups.com > > > Sent: Monday, February 19, 2007 8:02 PM > > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > > > > David, Bypass and override are two independent features. I > > believe > > > bypass is a safety feature for a clogged hydro oil filter. > > Bypass is > > > not triggered by the override dash switch > > > GregoryO'Connor > > > 94ptRomolandCa > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > > Hi Rich, > > > > > > > > Thanks for the help. When I return to the bus I'll try your > > test. > > > > I guess if the fan speed increases, then the problem is > between > > > > the dash switch and the "bypass valve". Alas, no wiring > > schematics.. > > > > I'll let you know what happens. > > > > > > > > > > > > David B > > > > '02 LXi, Smokey > > > > NC > > > > > > > > g_man1146 wrote: > > > > > Hi David, > > > > > > > > > > AS others have stated, a fan over-ride failure should fault > > to > > > high > > > > > speed. If you are not getting high fan speed with the air > > > conditioner > > > > > on or with the switch set to "over-ride" locate (assuming > > Detroit > > > S60) > > > > > a connector plug at the rear of the engine compartment > > (closest > > > to rear > > > > > bumper) on the fan side. You should see a hydraulic hose > > from the > > > fan > > > > > motor to this block (bypass valve) and wires coming from > it. > > If > > > you > > > > > disconnect the connector plug on these wires, the fan > should > > come > > > up to > > > > > full RPM. (ROAR) If it increases but not fully, the problem > > may > > > lie > > > > > with the hydraulic pump which is attached to the PTO on the > > curb > > > side > > > > > of the Allison or with the hydraulic bypass valve. BB makes > > > changes all > > > > > the time and my coach (3 years older) may not be set up the > > same. > > > If > > > > > you are not overheating on long hills everything may be > > normal. I > > > > > experienced an overheating situation only in extreme > > situations > > > and > > > > > determined the problem to be a faulty hydraulic pump > > supplied as > > > part > > > > > of the PTO recall from BB. The pump did not have sufficient > > > capacity to > > > > > run the fan at full speed. They supplied a new pump and > > labor to > > > > > install. The fan motor is actually rated at about 40 HP at > > full > > > > > capacity. No wonder it is designed to cut back when not > > needed! > > > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > > > wrote: > > > > > > > > > >> Folks, > > > > >> > > > > >> On my '02 LXi, with the engine at idle, the fan seems to > > rotate > > > > >> at 400 rpm or so (give or take, lol), when I enable the > > override > > > > >> switch there doesn't seem to be any change in fan speed. > > Should > > > > >> there be? or are there other parameters at work hear; > i.e., > > > engine > > > > >> temp, etc. What are the common failure modes of the fan > > override? > > > > >> > > > > >> Thanks, > > > > >> David Brady > > > > >> '02 LXi, Smokey > > > > >> NC > > > > >> > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > Coolant fan override switch - g_man1146 - 02-20-2007 03:11 Leroy, You are correct; the fan bypass defaults to closed, thereby forcing all of the pump output through the fan motor. Cool temperatures, air conditioner "ON" or "Fan Override" switch "ON" all hold the bypass valve open allowing oil to flow around the fan motor. When I was attempting to diagnose what turned out to be a defective pump, BB sent me a diagram and test procedure to follow. They said the LXi shared the same system as the "LTC" commercial coach. Rich D. '99LXi43' CT --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > Rich: I have a question on the bypass valve if you know. I do not have a drawing of the valve. > > As I understand the system, the fan is normally in idle(bypass) mode until one of three things happen. The alarmstat activates high mode based on water temperature, the fan override(manually by humans or grandkids) activates high mode or the chassis a/c on switch activates high mode. > Does the fan bypass valve default to fan high mode? . That would make sense otherwise the system would overheat with valve or electrical failure. If so, one could conclude that the piston in the valve is actuated by continuous power in the bypass position and the fan override, a/c switch and alarmstat cuts power off to it and it is spring loaded to full fan mode. > > If you know. Thanks. Trying to learn more here. > > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Niceville,FL > > > > > > > ----- Original Message ----- > From: Leroy Eckert > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 9:35 PM > Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch > > > That was to Greg, but I think we are all speaking of the same thing, just a different component in the system with a bypass. The fan control valve has a bypass as does the Parker filter. The override sends a message so to speak to the valve to stop the bypass and get into high mode. So does the chassis a/c on switch. If the valve is bad, the fan will not spool up. > > Leroy Eckert > 1990 WB-40"smoke N Mirrors" > Niceville, FL > > ----- Original Message ----- > From: g_man1146 > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 9:08 PM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > Gregory, > > On the later model Series 60's the fan bypass valve diverts > hydraulic oil around the fan motor to allow the fan to run at a > lower speed by sending the oil back without going through the > fan "motor". If the bypass valve fails, you get full RPM of the fan > as all of the oil is directed to the fan motor. This has nothing to > do with a filter bypass. The bypass valve can also be tested by > plugging the return line that goes to the bypass valve thus forcing > all oil through the fan motor. > > Rich D. '99LXi43' CT > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > Yes. > > > > Leroy Eckert > > 1990 WB-40"Smoke N Mirrors" > > Nicevile, FL > > > > > > ----- Original Message ----- > > From: Gregory OConnor > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 8:02 PM > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > David, Bypass and override are two independent features. I > believe > > bypass is a safety feature for a clogged hydro oil filter. > Bypass is > > not triggered by the override dash switch > > GregoryO'Connor > > 94ptRomolandCa > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > wrote: > > > > > > Hi Rich, > > > > > > Thanks for the help. When I return to the bus I'll try your > test. > > > I guess if the fan speed increases, then the problem is between > > > the dash switch and the "bypass valve". Alas, no wiring > schematics.. > > > I'll let you know what happens. > > > > > > > > > David B > > > '02 LXi, Smokey > > > NC > > > > > > g_man1146 wrote: > > > > Hi David, > > > > > > > > AS others have stated, a fan over-ride failure should fault > to > > high > > > > speed. If you are not getting high fan speed with the air > > conditioner > > > > on or with the switch set to "over-ride" locate (assuming > Detroit > > S60) > > > > a connector plug at the rear of the engine compartment > (closest > > to rear > > > > bumper) on the fan side. You should see a hydraulic hose > from the > > fan > > > > motor to this block (bypass valve) and wires coming from it. > If > > you > > > > disconnect the connector plug on these wires, the fan should > come > > up to > > > > full RPM. (ROAR) If it increases but not fully, the problem > may > > lie > > > > with the hydraulic pump which is attached to the PTO on the > curb > > side > > > > of the Allison or with the hydraulic bypass valve. BB makes > > changes all > > > > the time and my coach (3 years older) may not be set up the > same. > > If > > > > you are not overheating on long hills everything may be > normal. I > > > > experienced an overheating situation only in extreme > situations > > and > > > > determined the problem to be a faulty hydraulic pump > supplied as > > part > > > > of the PTO recall from BB. The pump did not have sufficient > > capacity to > > > > run the fan at full speed. They supplied a new pump and > labor to > > > > install. The fan motor is actually rated at about 40 HP at > full > > > > capacity. No wonder it is designed to cut back when not > needed! > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > >> Folks, > > > >> > > > >> On my '02 LXi, with the engine at idle, the fan seems to > rotate > > > >> at 400 rpm or so (give or take, lol), when I enable the > override > > > >> switch there doesn't seem to be any change in fan speed. > Should > > > >> there be? or are there other parameters at work hear; i.e., > > engine > > > >> temp, etc. What are the common failure modes of the fan > override? > > > >> > > > >> Thanks, > > > >> David Brady > > > >> '02 LXi, Smokey > > > >> NC > > > >> > > > >> > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > [Non-text portions of this message have been removed] > > > > > > [Non-text portions of this message have been removed] > Coolant fan override switch - Leroy Eckert - 02-20-2007 03:46 Ok, thanks. Now all I have to figure out is how any one of the three components disables the other two when in high mode. Somehow, the a/c and override switch must be tied to the Alarmstat NC sensor . I just haven't figured that one out. I want to make an electrical drawing of my system. If I figure it out, I'll post it. Thanks, Leroy Eckert 1990 WB-40"Smoke N Mirrors" Niceville, FL ----- Original Message ----- From: g_man1146 To: WanderlodgeForum@yahoogroups.com Sent: Tuesday, February 20, 2007 9:11 AM Subject: [WanderlodgeForum] Re: Coolant fan override switch Leroy, You are correct; the fan bypass defaults to closed, thereby forcing all of the pump output through the fan motor. Cool temperatures, air conditioner "ON" or "Fan Override" switch "ON" all hold the bypass valve open allowing oil to flow around the fan motor. When I was attempting to diagnose what turned out to be a defective pump, BB sent me a diagram and test procedure to follow. They said the LXi shared the same system as the "LTC" commercial coach. Rich D. '99LXi43' CT --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > Rich: I have a question on the bypass valve if you know. I do not have a drawing of the valve. > > As I understand the system, the fan is normally in idle(bypass) mode until one of three things happen. The alarmstat activates high mode based on water temperature, the fan override(manually by humans or grandkids) activates high mode or the chassis a/c on switch activates high mode. > Does the fan bypass valve default to fan high mode? . That would make sense otherwise the system would overheat with valve or electrical failure. If so, one could conclude that the piston in the valve is actuated by continuous power in the bypass position and the fan override, a/c switch and alarmstat cuts power off to it and it is spring loaded to full fan mode. > > If you know. Thanks. Trying to learn more here. > > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Niceville,FL > > > > > > > ----- Original Message ----- > From: Leroy Eckert > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 9:35 PM > Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch > > > That was to Greg, but I think we are all speaking of the same thing, just a different component in the system with a bypass. The fan control valve has a bypass as does the Parker filter. The override sends a message so to speak to the valve to stop the bypass and get into high mode. So does the chassis a/c on switch. If the valve is bad, the fan will not spool up. > > Leroy Eckert > 1990 WB-40"smoke N Mirrors" > Niceville, FL > > ----- Original Message ----- > From: g_man1146 > To: WanderlodgeForum@yahoogroups.com > Sent: Monday, February 19, 2007 9:08 PM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > Gregory, > > On the later model Series 60's the fan bypass valve diverts > hydraulic oil around the fan motor to allow the fan to run at a > lower speed by sending the oil back without going through the > fan "motor". If the bypass valve fails, you get full RPM of the fan > as all of the oil is directed to the fan motor. This has nothing to > do with a filter bypass. The bypass valve can also be tested by > plugging the return line that goes to the bypass valve thus forcing > all oil through the fan motor. > > Rich D. '99LXi43' CT > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > Yes. > > > > Leroy Eckert > > 1990 WB-40"Smoke N Mirrors" > > Nicevile, FL > > > > > > ----- Original Message ----- > > From: Gregory OConnor > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 8:02 PM > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > David, Bypass and override are two independent features. I > believe > > bypass is a safety feature for a clogged hydro oil filter. > Bypass is > > not triggered by the override dash switch > > GregoryO'Connor > > 94ptRomolandCa > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > wrote: > > > > > > Hi Rich, > > > > > > Thanks for the help. When I return to the bus I'll try your > test. > > > I guess if the fan speed increases, then the problem is between > > > the dash switch and the "bypass valve". Alas, no wiring > schematics.. > > > I'll let you know what happens. > > > > > > > > > David B > > > '02 LXi, Smokey > > > NC > > > > > > g_man1146 wrote: > > > > Hi David, > > > > > > > > AS others have stated, a fan over-ride failure should fault > to > > high > > > > speed. If you are not getting high fan speed with the air > > conditioner > > > > on or with the switch set to "over-ride" locate (assuming > Detroit > > S60) > > > > a connector plug at the rear of the engine compartment > (closest > > to rear > > > > bumper) on the fan side. You should see a hydraulic hose > from the > > fan > > > > motor to this block (bypass valve) and wires coming from it. > If > > you > > > > disconnect the connector plug on these wires, the fan should > come > > up to > > > > full RPM. (ROAR) If it increases but not fully, the problem > may > > lie > > > > with the hydraulic pump which is attached to the PTO on the > curb > > side > > > > of the Allison or with the hydraulic bypass valve. BB makes > > changes all > > > > the time and my coach (3 years older) may not be set up the > same. > > If > > > > you are not overheating on long hills everything may be > normal. I > > > > experienced an overheating situation only in extreme > situations > > and > > > > determined the problem to be a faulty hydraulic pump > supplied as > > part > > > > of the PTO recall from BB. The pump did not have sufficient > > capacity to > > > > run the fan at full speed. They supplied a new pump and > labor to > > > > install. The fan motor is actually rated at about 40 HP at > full > > > > capacity. No wonder it is designed to cut back when not > needed! > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > >> Folks, > > > >> > > > >> On my '02 LXi, with the engine at idle, the fan seems to > rotate > > > >> at 400 rpm or so (give or take, lol), when I enable the > override > > > >> switch there doesn't seem to be any change in fan speed. > Should > > > >> there be? or are there other parameters at work hear; i.e., > > engine > > > >> temp, etc. What are the common failure modes of the fan > override? > > > >> > > > >> Thanks, > > > >> David Brady > > > >> '02 LXi, Smokey > > > >> NC > > > >> > > > >> > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > [Non-text portions of this message have been removed] > > > > > > [Non-text portions of this message have been removed] > [Non-text portions of this message have been removed] Coolant fan override switch - David Brady - 02-20-2007 11:48 Leroy, From a circuit standpoint, I think you're looking for an Open Collector Output on each of the signals: a/c, override switch, and alarmstat. All three would then be tied together and pulled up with a power source and a resistor. This signal could then be fed into the bypass switch. When all signals are off, the pull up resistor supplies power to the bypass enabling the piston and the slow fan speed. When one or more of the input signals drives it's Open Collector output to ground, the pull up resistor will be driven to ground and in turn the input to the bypass switch will be ground resulting in the release of the piston and a high fan speed. If the power source goes away, then the input to the bypass switch loses it's voltage and the bypass defaults to high fans speed. This can easily be implemented with transistors, relays are another story... David Brady '02 LXi, Smokey NC Leroy Eckert wrote: > Ok, thanks. Now all I have to figure out is how any one of the three components disables the other two when in high mode. Somehow, the a/c and override switch must be tied to the Alarmstat NC sensor . I just haven't figured that one out. I want to make an electrical drawing of my system. If I figure it out, I'll post it. > > Thanks, > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Niceville, FL > > > > ----- Original Message ----- > From: g_man1146 > To: WanderlodgeForum@yahoogroups.com > Sent: Tuesday, February 20, 2007 9:11 AM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > Leroy, > You are correct; the fan bypass defaults to closed, thereby forcing > all of the pump output through the fan motor. Cool temperatures, air > conditioner "ON" or "Fan Override" switch "ON" all hold the bypass > valve open allowing oil to flow around the fan motor. When I was > attempting to diagnose what turned out to be a defective pump, BB > sent me a diagram and test procedure to follow. They said the LXi > shared the same system as the "LTC" commercial coach. > > Rich D. '99LXi43' CT > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > Rich: I have a question on the bypass valve if you know. I do not > have a drawing of the valve. > > > > As I understand the system, the fan is normally in idle(bypass) > mode until one of three things happen. The alarmstat activates high > mode based on water temperature, the fan override(manually by humans > or grandkids) activates high mode or the chassis a/c on switch > activates high mode. > > Does the fan bypass valve default to fan high mode? . That would > make sense otherwise the system would overheat with valve or > electrical failure. If so, one could conclude that the piston in the > valve is actuated by continuous power in the bypass position and the > fan override, a/c switch and alarmstat cuts power off to it and it is > spring loaded to full fan mode. > > > > If you know. Thanks. Trying to learn more here. > > > > > > Leroy Eckert > > 1990 WB-40"Smoke N Mirrors" > > Niceville,FL > > > > > > > > > > > > > > ----- Original Message ----- > > From: Leroy Eckert > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 9:35 PM > > Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > That was to Greg, but I think we are all speaking of the same > thing, just a different component in the system with a bypass. The > fan control valve has a bypass as does the Parker filter. The > override sends a message so to speak to the valve to stop the bypass > and get into high mode. So does the chassis a/c on switch. If the > valve is bad, the fan will not spool up. > > > > Leroy Eckert > > 1990 WB-40"smoke N Mirrors" > > Niceville, FL > > > > ----- Original Message ----- > > From: g_man1146 > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 9:08 PM > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > Gregory, > > > > On the later model Series 60's the fan bypass valve diverts > > hydraulic oil around the fan motor to allow the fan to run at a > > lower speed by sending the oil back without going through the > > fan "motor". If the bypass valve fails, you get full RPM of the > fan > > as all of the oil is directed to the fan motor. This has nothing > to > > do with a filter bypass. The bypass valve can also be tested by > > plugging the return line that goes to the bypass valve thus > forcing > > all oil through the fan motor. > > > > Rich D. '99LXi43' CT > > > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > > > > Yes. > > > > > > Leroy Eckert > > > 1990 WB-40"Smoke N Mirrors" > > > Nicevile, FL > > > > > > > > > ----- Original Message ----- > > > From: Gregory OConnor > > > To: WanderlodgeForum@yahoogroups.com > > > Sent: Monday, February 19, 2007 8:02 PM > > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > > > > David, Bypass and override are two independent features. I > > believe > > > bypass is a safety feature for a clogged hydro oil filter. > > Bypass is > > > not triggered by the override dash switch > > > GregoryO'Connor > > > 94ptRomolandCa > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > > Hi Rich, > > > > > > > > Thanks for the help. When I return to the bus I'll try your > > test. > > > > I guess if the fan speed increases, then the problem is > between > > > > the dash switch and the "bypass valve". Alas, no wiring > > schematics.. > > > > I'll let you know what happens. > > > > > > > > > > > > David B > > > > '02 LXi, Smokey > > > > NC > > > > > > > > g_man1146 wrote: > > > > > Hi David, > > > > > > > > > > AS others have stated, a fan over-ride failure should fault > > to > > > high > > > > > speed. If you are not getting high fan speed with the air > > > conditioner > > > > > on or with the switch set to "over-ride" locate (assuming > > Detroit > > > S60) > > > > > a connector plug at the rear of the engine compartment > > (closest > > > to rear > > > > > bumper) on the fan side. You should see a hydraulic hose > > from the > > > fan > > > > > motor to this block (bypass valve) and wires coming from > it. > > If > > > you > > > > > disconnect the connector plug on these wires, the fan > should > > come > > > up to > > > > > full RPM. (ROAR) If it increases but not fully, the problem > > may > > > lie > > > > > with the hydraulic pump which is attached to the PTO on the > > curb > > > side > > > > > of the Allison or with the hydraulic bypass valve. BB makes > > > changes all > > > > > the time and my coach (3 years older) may not be set up the > > same. > > > If > > > > > you are not overheating on long hills everything may be > > normal. I > > > > > experienced an overheating situation only in extreme > > situations > > > and > > > > > determined the problem to be a faulty hydraulic pump > > supplied as > > > part > > > > > of the PTO recall from BB. The pump did not have sufficient > > > capacity to > > > > > run the fan at full speed. They supplied a new pump and > > labor to > > > > > install. The fan motor is actually rated at about 40 HP at > > full > > > > > capacity. No wonder it is designed to cut back when not > > needed! > > > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > > > wrote: > > > > > > > > > >> Folks, > > > > >> > > > > >> On my '02 LXi, with the engine at idle, the fan seems to > > rotate > > > > >> at 400 rpm or so (give or take, lol), when I enable the > > override > > > > >> switch there doesn't seem to be any change in fan speed. > > Should > > > > >> there be? or are there other parameters at work hear; > i.e., > > > engine > > > > >> temp, etc. What are the common failure modes of the fan > > override? > > > > >> > > > > >> Thanks, > > > > >> David Brady > > > > >> '02 LXi, Smokey > > > > >> NC > > > > >> > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > Coolant fan override switch - Leroy Eckert - 02-20-2007 14:28 Thanks, I had concluded that some sort of collector box or terminal strip would be needed because the three components must have power until actuation. Since any one of the three can independently place the fan in high mode I couldn't follow it. I called BB and Jessie said he would see if he can find a schematic. Everything works fine now but I would like to document it in my Bluebox just in case, primarily because I intend to sleep between now and the time of failure. lol Thanks, Leroy Eckert 1990 WB-40"Smoke N Mirrors" Niceville, FL ----- Original Message ----- From: David Brady To: WanderlodgeForum@yahoogroups.com Sent: Tuesday, February 20, 2007 5:48 PM Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch Leroy, From a circuit standpoint, I think you're looking for an Open Collector Output on each of the signals: a/c, override switch, and alarmstat. All three would then be tied together and pulled up with a power source and a resistor. This signal could then be fed into the bypass switch. When all signals are off, the pull up resistor supplies power to the bypass enabling the piston and the slow fan speed. When one or more of the input signals drives it's Open Collector output to ground, the pull up resistor will be driven to ground and in turn the input to the bypass switch will be ground resulting in the release of the piston and a high fan speed. If the power source goes away, then the input to the bypass switch loses it's voltage and the bypass defaults to high fans speed. This can easily be implemented with transistors, relays are another story... David Brady '02 LXi, Smokey NC Leroy Eckert wrote: > Ok, thanks. Now all I have to figure out is how any one of the three components disables the other two when in high mode. Somehow, the a/c and override switch must be tied to the Alarmstat NC sensor . I just haven't figured that one out. I want to make an electrical drawing of my system. If I figure it out, I'll post it. > > Thanks, > > Leroy Eckert > 1990 WB-40"Smoke N Mirrors" > Niceville, FL > > > > ----- Original Message ----- > From: g_man1146 > To: WanderlodgeForum@yahoogroups.com > Sent: Tuesday, February 20, 2007 9:11 AM > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > Leroy, > You are correct; the fan bypass defaults to closed, thereby forcing > all of the pump output through the fan motor. Cool temperatures, air > conditioner "ON" or "Fan Override" switch "ON" all hold the bypass > valve open allowing oil to flow around the fan motor. When I was > attempting to diagnose what turned out to be a defective pump, BB > sent me a diagram and test procedure to follow. They said the LXi > shared the same system as the "LTC" commercial coach. > > Rich D. '99LXi43' CT > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > Rich: I have a question on the bypass valve if you know. I do not > have a drawing of the valve. > > > > As I understand the system, the fan is normally in idle(bypass) > mode until one of three things happen. The alarmstat activates high > mode based on water temperature, the fan override(manually by humans > or grandkids) activates high mode or the chassis a/c on switch > activates high mode. > > Does the fan bypass valve default to fan high mode? . That would > make sense otherwise the system would overheat with valve or > electrical failure. If so, one could conclude that the piston in the > valve is actuated by continuous power in the bypass position and the > fan override, a/c switch and alarmstat cuts power off to it and it is > spring loaded to full fan mode. > > > > If you know. Thanks. Trying to learn more here. > > > > > > Leroy Eckert > > 1990 WB-40"Smoke N Mirrors" > > Niceville,FL > > > > > > > > > > > > > > ----- Original Message ----- > > From: Leroy Eckert > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 9:35 PM > > Subject: Re: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > That was to Greg, but I think we are all speaking of the same > thing, just a different component in the system with a bypass. The > fan control valve has a bypass as does the Parker filter. The > override sends a message so to speak to the valve to stop the bypass > and get into high mode. So does the chassis a/c on switch. If the > valve is bad, the fan will not spool up. > > > > Leroy Eckert > > 1990 WB-40"smoke N Mirrors" > > Niceville, FL > > > > ----- Original Message ----- > > From: g_man1146 > > To: WanderlodgeForum@yahoogroups.com > > Sent: Monday, February 19, 2007 9:08 PM > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > Gregory, > > > > On the later model Series 60's the fan bypass valve diverts > > hydraulic oil around the fan motor to allow the fan to run at a > > lower speed by sending the oil back without going through the > > fan "motor". If the bypass valve fails, you get full RPM of the > fan > > as all of the oil is directed to the fan motor. This has nothing > to > > do with a filter bypass. The bypass valve can also be tested by > > plugging the return line that goes to the bypass valve thus > forcing > > all oil through the fan motor. > > > > Rich D. '99LXi43' CT > > > > --- In WanderlodgeForum@yahoogroups.com, "Leroy Eckert" > > > > > > > > Yes. > > > > > > Leroy Eckert > > > 1990 WB-40"Smoke N Mirrors" > > > Nicevile, FL > > > > > > > > > ----- Original Message ----- > > > From: Gregory OConnor > > > To: WanderlodgeForum@yahoogroups.com > > > Sent: Monday, February 19, 2007 8:02 PM > > > Subject: [WanderlodgeForum] Re: Coolant fan override switch > > > > > > > > > David, Bypass and override are two independent features. I > > believe > > > bypass is a safety feature for a clogged hydro oil filter. > > Bypass is > > > not triggered by the override dash switch > > > GregoryO'Connor > > > 94ptRomolandCa > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > wrote: > > > > > > > > Hi Rich, > > > > > > > > Thanks for the help. When I return to the bus I'll try your > > test. > > > > I guess if the fan speed increases, then the problem is > between > > > > the dash switch and the "bypass valve". Alas, no wiring > > schematics.. > > > > I'll let you know what happens. > > > > > > > > > > > > David B > > > > '02 LXi, Smokey > > > > NC > > > > > > > > g_man1146 wrote: > > > > > Hi David, > > > > > > > > > > AS others have stated, a fan over-ride failure should fault > > to > > > high > > > > > speed. If you are not getting high fan speed with the air > > > conditioner > > > > > on or with the switch set to "over-ride" locate (assuming > > Detroit > > > S60) > > > > > a connector plug at the rear of the engine compartment > > (closest > > > to rear > > > > > bumper) on the fan side. You should see a hydraulic hose > > from the > > > fan > > > > > motor to this block (bypass valve) and wires coming from > it. > > If > > > you > > > > > disconnect the connector plug on these wires, the fan > should > > come > > > up to > > > > > full RPM. (ROAR) If it increases but not fully, the problem > > may > > > lie > > > > > with the hydraulic pump which is attached to the PTO on the > > curb > > > side > > > > > of the Allison or with the hydraulic bypass valve. BB makes > > > changes all > > > > > the time and my coach (3 years older) may not be set up the > > same. > > > If > > > > > you are not overheating on long hills everything may be > > normal. I > > > > > experienced an overheating situation only in extreme > > situations > > > and > > > > > determined the problem to be a faulty hydraulic pump > > supplied as > > > part > > > > > of the PTO recall from BB. The pump did not have sufficient > > > capacity to > > > > > run the fan at full speed. They supplied a new pump and > > labor to > > > > > install. The fan motor is actually rated at about 40 HP at > > full > > > > > capacity. No wonder it is designed to cut back when not > > needed! > > > > > > > > > > Rich D. '99LXi43' CT > > > > > > > > > > --- In WanderlodgeForum@yahoogroups.com, David Brady > > > > > wrote: > > > > > > > > > >> Folks, > > > > >> > > > > >> On my '02 LXi, with the engine at idle, the fan seems to > > rotate > > > > >> at 400 rpm or so (give or take, lol), when I enable the > > override > > > > >> switch there doesn't seem to be any change in fan speed. > > Should > > > > >> there be? or are there other parameters at work hear; > i.e., > > > engine > > > > >> temp, etc. What are the common failure modes of the fan > > override? > > > > >> > > > > >> Thanks, > > > > >> David Brady > > > > >> '02 LXi, Smokey > > > > >> NC > > > > >> > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > [Non-text portions of this message have been removed] > > > > > Yahoo! Groups Links > > > > > > [Non-text portions of this message have been removed] |