Coolant fan override switch

[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"
> wrote:
> >
> > 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]
> >
>