Radiator temp in/out and temp gauge readings

[mrdonut12]

--- In WanderlodgeForum@yahoogroups.com, "transit360"
wrote:
> George,
>
>
> And I'm taking it that there is NO possible way that you think
a
> bad thermostat can be diagnosed without taking it out. I won't
argue
> with you since you have the experience. Thanks again for your
input.
You're welcome and thanks for the nice response. :o)
There are several thermostat tests. The first and easiest is to
start the engine completely cold, run it a few minutes and feel the
top of the radiator. If it gets warm at all within a few minutes,
the thermostat isn't closing completely. This is the first sign of a
weak thermostat, it doesn't seal up cold. This doesn't require a
Raytek.
The next test does require a Raytek. The output temp of the
upper radiator hose should stay fairly level until the thermostat
opens, at which time the temp should just shoot up suddenly to the
170 degree or more area. This indicates the thermostat has opened.
The temp may toggle up and down slightly as the thermostat cycles.
Those are the thermostat tests.
The real reason I suggested replacement of the thermostat is it
really is a wearout item and it's job is critical to keep the engine
temperature constant. A 10 degree deviation has a lot of effect on
the efficiency of the engine and the longevity of it. I replace mine
every 3 years as a maintenance item.
The first thing I did after I bought my Bird was to replace the
thermostats in both the engine and the generator. Both were found to
be worn out on physical examination. Just because it passes those
tests doesn't mean it will be reliable in the future.
Hope this helps.

George Witt
81 FC 35
Lincoln, Nebraska
>
> Steve
> 2 '98 QBRE Bluebird
>
>
>
> --- In WanderlodgeForum@yahoogroups.com, "mrdonut12"
> <mrdonut12@y...> wrote:
> >
> > Steve,
> > Forgive me if I'm a little short with you, but I'm a
> professional
> > mechanic with over 30 years experience, ASE Certified Master
> > Technician, Advanced L-1 Engine Performance Certification,
> > Service Advisor Certification and I own one of the best auto
repair
> > shops in the US. In 10 years in business, my shop has fixed over
> > 34,000 cars.
> > I told you 3 weeks ago, the first step in fixing this thing
> is
> > to install new factory thermostats. You have to establish
> baselines
> > of performance in a system in order to fix it. No other part of
> the
> > cooling system can be properly evaluated with malfunctioning
> > thermostats in place.
> > Thermostats get old, they wear out and they break.
> > You asked my advice, I gave it to you, you argued with me
and
> > went out and bought a new toy that costs about 7 times what a
> > thermostat would cost and now you want me to answer more
questions.
> > My question to you is, do you want to screw around or do you
> want
> > to fix this thing?
> >
> > George Witt
> > 81 FC 35
> > Lincoln, Nebraska
> >
> > --- In WanderlodgeForum@yahoogroups.com, "transit360"
> > wrote:
> > > Tom and George,
> > >
> > > OK, sorry guys. I forgot to mention I also shot a temp
> reading on
> > > the hose going in and out of the water pump, both at around 200
> > > degrees also.
> > > To be honest with you, I'm not sure where my thermostat
is.
> I'm
> > > assuming it's in a usual spot near the water pump, but I've
> never
> > > worked on the 8.3 Cummins before, and I've been trying to find
a
> > > manual for a month. But it should be a no-brainer.
> > > So I'm gathering that we're suspecting improper coolant
> flow,
> > > which could be caused by a stuck thermostat or possibly a weak
> water
> > > pump? I'm assuming when I locate the thermostat that I should
be
> > > able to shoot it at operating temp and the temp should be the
> same
> > > on both sides, otherwise a temp difference would indicate it's
> > > closed, yes? Sounds feasible.
> > > However, this is pretty much how this bus has always
run,
> > > around 200 degrees on the highway. Wouldn't it overheat if the
> > > thermostat stayed closed? Could it be partially open or closed?
> That
> > > would restrict flow but maybe not enough to totally overheat
the
> > > engine?
> > >
> > > Thanks,
> > > Steve
> > > 2 '98 Bluebird QBRE Partybuses
> > >
> > > --- In WanderlodgeForum@yahoogroups.com, Tom Warner
>
> > > wrote:
> > > > George what he established is that the radiator is not
> exhanging
> > > heat.
> > > > There should be only about a 10-15 degree difference between
> the
> > > temp at
> > > > the top and bottom. If not the coolant is not flowing more
> then
> > > likely
> > > > because the thermostat is not open.
> > > >
> > > > tom
> > > > 1982 FC35
> > > > Vernon Center,Ny
> > > >
> > > > At 02:15 AM 7/20/2005 +0000, you wrote:
> > > > >Steve,
> > > > > You've established that the radiator, at the current
flow
> > > > >rate, is capable of exchanging heat.
> > > > > What you haven't established is if there's any water
> flow.
> > > > >With that deep a drop in temperature, does that tell you
that
> > > maybe
> > > > >the coolant is flowing too slowly?
> > > > > Use your Raytek infrared temp gun to tell you if the
> > > thermostat
> > > > >is working properly.
> > > > >
> > > > > George Witt
> > > > > 81 FC 35
> > > > > Lincoln, Nebraska
> > > > >
> > > > >
> > > > >--- In WanderlodgeForum@yahoogroups.com, "transit360"
> > > > > wrote:
> > > > > > I just got my new Raytek infrared temp gun and was
> getting
> > > some
> > > > > > shots on my 8.3 Cummins pusher in my '98 QBRE Partybus. I
> shot
> > > the
> > > > > > top of the radiator and it read 200 degrees, which is
what
> my
> > > bus
> > > > > > temp gauge said. I shot the lower radiator hose and it
> read 130
> > > > > > degrees.
> > > > > > I made sure to test location and reposition my gun
> several
> > > > > > times, and this is what I got. Should there be such a
> drastic
> > > change
> > > > > > in temp through the radiator? I was expecting about 15-20
> > > degrees
> > > > > > difference. Could this indicate any problems?
> > > > > >
> > > > > > Second question: My temp gauge on the dash has green
> (safe)
> > > > > > markings up to 220 degrees. Past 220, it reads in the
red.
> My
> > > bird
> > > > > > typically runs at 200 degrees while riding. Is this
> normal?
> > > Seems a
> > > > > > little on the warm side but this is my first Cummins as I
> have
> > > dealt
> > > > > > primarily with 8.2 and 6V71 Detroits in the past. My
other
> > > Bluebird
> > > > > > partybus (same exact bus) runs at about 190, although I
> haven't
> > > > > > confirmed it with the temp gun like the first.
> > > > > >
> > > > > > Thanks,
> > > > > > Steve
> > > > > > 2 '98 Bluebird QBRE Partybuses
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >----------
> > > > >YAHOO! GROUPS LINKS
> > > > >
> > > > > * Visit your group
> > > >
> > >
>
> "<http://groups.yahoo.com/group/WanderlodgeForum>WanderlodgeForum"
> > > on the web.
> > > > > *
> > > > > * To unsubscribe from this group, send an email to:
> > > > > *
> > > > > > > > subject=Unsubscribe>WanderlodgeForum-
unsubscribe@yahoogroups.com
> > > > >
> > > > > *
> > > > > * Your use of Yahoo! Groups is subject to the
> > > > > <http://docs.yahoo.com/info/terms/>Yahoo! Terms of Service.
> > > > >
> > > > >
> > > > >----------