Chassis heat problems

[Don Bradner]

Until a few days ago, my chassis heat was working fine, now it is dead.

The chassis heat on this coach is a lot simpler than has been described for many
others. No summer/winter valves, no always-on Sporlans, no Webasto or Primus.

The water system consists of a single Sporlan valve and a pump, both actuated by
a slide switch in the cockpit (below the backup monitor controls). The valve
should open and the pump turn on whenever the switch is in the Warm position and
the ignition key is on.

When this is done (engine off in order to hear things), there is a discernible
click at the Sporlan, and the pump starts. After a few seconds, a circuit
breaker can be heard to pop, and it goes off. Maybe ten seconds later the
breaker resets and things run for a few seconds more.

Question: Could this be a stuck Sporlan (pump blowing breaker because of back
pressure)? I've looked through the various documents available and don't see a
good way to test a Sporlan valve.

Don Bradner
90 PT40 "Blue Thunder"
Posting today by satellite from Pea Soup Andersen's, Santa Nella, CA

[Stephen Birtles]

I would be checking the pump first in case the impeller is gone and
jamming the motor

Stephen 77fc35 with new pumps and sporlan kits in stock
http://www.dupreeproducts.com

--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> Until a few days ago, my chassis heat was working fine, now it is dead.
>
> The chassis heat on this coach is a lot simpler than has been
described for many others. No summer/winter valves, no always-on
Sporlans, no Webasto or Primus.
>
> The water system consists of a single Sporlan valve and a pump, both
actuated by a slide switch in the cockpit (below the backup monitor
controls). The valve should open and the pump turn on whenever the
switch is in the Warm position and the ignition key is on.
>
> When this is done (engine off in order to hear things), there is a
discernible click at the Sporlan, and the pump starts. After a few
seconds, a circuit breaker can be heard to pop, and it goes off. Maybe
ten seconds later the breaker resets and things run for a few seconds
more.
>
> Question: Could this be a stuck Sporlan (pump blowing breaker
because of back pressure)? I've looked through the various documents
available and don't see a good way to test a Sporlan valve.
>
> Don Bradner
> 90 PT40 "Blue Thunder"
> Posting today by satellite from Pea Soup Andersen's, Santa Nella, CA
>

[Gregory OConnor]

Don, Your theory sounds good. running the pump wet ,primed and
against a closed supply is like trying to get fuel out of an
unvented tank.

Wonder if it is just bearings in the pumps motor or crap in the
impeller (which will screw the bearings anyway). I would pull the
pump and bench test it maybe some one knows the amp dray it is
designed to pull. if it pulls more on the bench with a goud source,
chances are it is time for a new. If the Sporlan is a vacumn
Diaphram valve they fail to close more often then fail to open. If
it is a valve problem it may well be crap on the supply side of the
sporlan or a screen doing what you describe to the pump.

GregoryO'Connor
94ptRomolandCa

--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> Until a few days ago, my chassis heat was working fine, now it is
dead.
>
> The chassis heat on this coach is a lot simpler than has been
described for many others. No summer/winter valves, no always-on
Sporlans, no Webasto or Primus.
>
> The water system consists of a single Sporlan valve and a pump,
both actuated by a slide switch in the cockpit (below the backup
monitor controls). The valve should open and the pump turn on
whenever the switch is in the Warm position and the ignition key is
on.
>
> When this is done (engine off in order to hear things), there is a
discernible click at the Sporlan, and the pump starts. After a few
seconds, a circuit breaker can be heard to pop, and it goes off.
Maybe ten seconds later the breaker resets and things run for a few
seconds more.
>
> Question: Could this be a stuck Sporlan (pump blowing breaker
because of back pressure)? I've looked through the various documents
available and don't see a good way to test a Sporlan valve.
>
> Don Bradner
> 90 PT40 "Blue Thunder"
> Posting today by satellite from Pea Soup Andersen's, Santa Nella,
CA
>

[ronmarabito2002]

Don: Have you checked to make sure your manual valves on the engine
are open. These valves are notorious for vibrating into a closed
position.

R.E. (Ron) Marabito, Dallas, TX 92WB40

--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> Until a few days ago, my chassis heat was working fine, now it is dead.
>
> The chassis heat on this coach is a lot simpler than has been
described for many others. No summer/winter valves, no always-on
Sporlans, no Webasto or Primus.
>
> The water system consists of a single Sporlan valve and a pump, both
actuated by a slide switch in the cockpit (below the backup monitor
controls). The valve should open and the pump turn on whenever the
switch is in the Warm position and the ignition key is on.
>
> When this is done (engine off in order to hear things), there is a
discernible click at the Sporlan, and the pump starts. After a few
seconds, a circuit breaker can be heard to pop, and it goes off. Maybe
ten seconds later the breaker resets and things run for a few seconds
more.
>
> Question: Could this be a stuck Sporlan (pump blowing breaker
because of back pressure)? I've looked through the various documents
available and don't see a good way to test a Sporlan valve.
>
> Don Bradner
> 90 PT40 "Blue Thunder"
> Posting today by satellite from Pea Soup Andersen's, Santa Nella, CA
>

[Don Bradner]

Yes, someone has nylon-tied them open.

On 3/3/2008 at 4:36 AM ronmarabito2002 wrote:

>Don: Have you checked to make sure your manual valves on the engine
>are open. These valves are notorious for vibrating into a closed
>position.
>
>R.E. (Ron) Marabito, Dallas, TX 92WB40
>
>--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
> wrote:
>>
>> Until a few days ago, my chassis heat was working fine, now it is dead.
>>
>> The chassis heat on this coach is a lot simpler than has been
>described for many others. No summer/winter valves, no always-on
>Sporlans, no Webasto or Primus.
>>
>> The water system consists of a single Sporlan valve and a pump, both
>actuated by a slide switch in the cockpit (below the backup monitor
>controls). The valve should open and the pump turn on whenever the
>switch is in the Warm position and the ignition key is on.
>>
>> When this is done (engine off in order to hear things), there is a
>discernible click at the Sporlan, and the pump starts. After a few
>seconds, a circuit breaker can be heard to pop, and it goes off. Maybe
>ten seconds later the breaker resets and things run for a few seconds
>more.
>>
>> Question: Could this be a stuck Sporlan (pump blowing breaker
>because of back pressure)? I've looked through the various documents
>available and don't see a good way to test a Sporlan valve.
>>
>> Don Bradner
>> 90 PT40 "Blue Thunder"
>> Posting today by satellite from Pea Soup Andersen's, Santa Nella, CA
>>
>
>
>
>
>
>Yahoo! Groups Links
>
>
>

[Don Bradner]

Revisting this one: As far as I can tell, the pump and sporlan valve are
functioning correctly (can see the pump, and took the valve apart, at which
point I can observe that the pump is pumping). The slide switch that controls
heat is attached to a circuit board that is a timer circuit. Output is either
+12V, or nothing, and the further to the right you move it the longer the
on-cycle lasts. There is no full-on condition. The cycling I heard appears to be
normal, and what I thought was a breaker is a relay, #12 in the front nose
panel.

I was alerted me to the presence of another valve, located under the top front
step. It is difficult to reach, and I investigated it using a camera. I can put
a hand on it, and there is no obvious vibration or sound when the relay kicks
the other valve and the pump cycles. The valve does not exactly match what was
described, but it is certainly in the water line to the front heater core. There
may not be any decent way to test it except by pulling it out, not a fun job.

Picture of the valve at http://www.arcatapet.net/image/heatvalve.jpg

On 3/2/2008 at 5:06 PM Don Bradner wrote:

>Until a few days ago, my chassis heat was working fine, now it is dead.
>
>The chassis heat on this coach is a lot simpler than has been described
>for many others. No summer/winter valves, no always-on Sporlans, no
>Webasto or Primus.
>
>The water system consists of a single Sporlan valve and a pump, both
>actuated by a slide switch in the cockpit (below the backup monitor
>controls). The valve should open and the pump turn on whenever the switch
>is in the Warm position and the ignition key is on.
>
>When this is done (engine off in order to hear things), there is a
>discernible click at the Sporlan, and the pump starts. After a few
>seconds, a circuit breaker can be heard to pop, and it goes off. Maybe ten
>seconds later the breaker resets and things run for a few seconds more.
>
>Question: Could this be a stuck Sporlan (pump blowing breaker because of
>back pressure)? I've looked through the various documents available and
>don't see a good way to test a Sporlan valve.
>
>Don Bradner
>90 PT40 "Blue Thunder"
>Posting today by satellite from Pea Soup Andersen's, Santa Nella, CA
>
>
>
>
>
>Yahoo! Groups Links
>
>
>

[Gregory OConnor]

Could be the pump works when not held against a closed loop???? maybe
the return line is simply plugged up. or your fan is staying on, and
the detroit isnt getting hot??

The camera trick is one CurtS taught me to do. I have even taken 10
meg picks of part labels then was able to read them on the computer
screen.

When you look at all the controls and appliances exposed to the
weather on these rigs it is a wonder that anything works.

GregoryO'Connor
94ptRomolandCa

[Don Bradner]

My concern is that the front valve may be the plug in the loop, if it is not
opening. Temperature of the engine is not an issue - I ran it at idle today up
to about 160 so that I would have it warm enough to be sure to feel the heat.
All lines stayed cold, including the top of the pump, until I allowed the pump
to run open via the dismantled Sporlan. Only took a couple of quarts of coolant
spilled to heat up everything through the pump to the valve.

On 3/15/2008 at 4:25 AM Gregory OConnor wrote:

>Could be the pump works when not held against a closed loop???? maybe
>the return line is simply plugged up. or your fan is staying on, and
>the detroit isnt getting hot??
>
>The camera trick is one CurtS taught me to do. I have even taken 10
>meg picks of part labels then was able to read them on the computer
>screen.
>
>When you look at all the controls and appliances exposed to the
>weather on these rigs it is a wonder that anything works.
>
>GregoryO'Connor
>94ptRomolandCa

[Gregory OConnor]

If you cant remove the valve maybe try and bypass it to see that
that is the problem first???? KevinMk did that with a remote air
regulator or somthing????
GregoryO'Connor
94ptRomolandCa

--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> My concern is that the front valve may be the plug in the loop, if
it is not opening. Temperature of the engine is not an issue - I ran
it at idle today up to about 160 so that I would have it warm enough
to be sure to feel the heat. All lines stayed cold, including the
top of the pump, until I allowed the pump to run open via the
dismantled Sporlan. Only took a couple of quarts of coolant spilled
to heat up everything through the pump to the valve.
>
> On 3/15/2008 at 4:25 AM Gregory OConnor wrote:
>
> >Could be the pump works when not held against a closed loop????
maybe
> >the return line is simply plugged up. or your fan is staying on,
and
> >the detroit isnt getting hot??
> >
> >The camera trick is one CurtS taught me to do. I have even taken
10
> >meg picks of part labels then was able to read them on the
computer
> >screen.
> >
> >When you look at all the controls and appliances exposed to the
> >weather on these rigs it is a wonder that anything works.
> >
> >GregoryO'Connor
> >94ptRomolandCa
>

[Don Bradner]

Well, it is back to the drawing board. The valve has been removed and replaced,
and the voltage tested. What I learned:

The valve up front is a normally-open valve, closed by power coming from the
timing circuit. Plus 12 volts is fed down to the valve, then back through
another wire to (somewhere) that gets power to the #12 relay. When the relay is
powered, there is no power to the circulation pump or the Sporlan valve.

So, power on, both valves are closed, one by the presence of power, the other by
the absence of power, and the pump is off.

When the valve was re-installed I left the power connection off, so the valve
was open (bench test had shown it working, and it was left in the open
position). When the key was turned on, the Sporlan opened, and the pump ran
continuously. The pump never faltered, but nothing in the system got even warm
to the touch (outside temp in the 40s, engine about 160).

I pulled the top of the pump off and managed to lose about 4 gallons of coolant
in the process - certainly the supply side of the pump is unobstructed! Replaced
the gasket and reassembled, after ascertaining that the pump runs well and there
is no damage to any of the impellor blades.

Both gate valves are wide open, which I assume is the correct setting (and I
presume they should have been closed before I messed with the pump!)

Looking for new possiblities, if anyone has any ideas.

Don Bradner
90 PT40 "Blue Thunder"
Eureka, CA

On 3/15/2008 at 5:52 AM Gregory OConnor wrote:

>If you cant remove the valve maybe try and bypass it to see that
>that is the problem first???? KevinMk did that with a remote air
>regulator or somthing????
>GregoryO'Connor
>94ptRomolandCa
>
>--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
> wrote:
>>
>> My concern is that the front valve may be the plug in the loop, if
>it is not opening. Temperature of the engine is not an issue - I ran
>it at idle today up to about 160 so that I would have it warm enough
>to be sure to feel the heat. All lines stayed cold, including the
>top of the pump, until I allowed the pump to run open via the
>dismantled Sporlan. Only took a couple of quarts of coolant spilled
>to heat up everything through the pump to the valve.
>>
>> On 3/15/2008 at 4:25 AM Gregory OConnor wrote:
>>
>> >Could be the pump works when not held against a closed loop????
>maybe
>> >the return line is simply plugged up. or your fan is staying on,
>and
>> >the detroit isnt getting hot??
>> >
>> >The camera trick is one CurtS taught me to do. I have even taken
>10
>> >meg picks of part labels then was able to read them on the
>computer
>> >screen.
>> >
>> >When you look at all the controls and appliances exposed to the
>> >weather on these rigs it is a wonder that anything works.
>> >
>> >GregoryO'Connor
>> >94ptRomolandCa
>>
>
>
>
>------------------------------------
>
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