A quick test is to start the cat cold. Feel the bypass hose and when it
starts to feel warm feel the upper radiator hose. If it also feels warm you
have a thermostat stuck partially open. The only real test is to remove the
thermostats and visually check and test them. I had one stuck partially
open and the second would not fully open. The symptoms were slow warming
up, temperature that tended to vary with speed, and excessive fan operation.
After replacement the engine would be up to temp by the time we get out of
our subdivision, the engine temperature is very stable, and the only time
the fan runs is creeping in traffic or the grade between El Centro and San
Diego. By the time I went to the work to pull them our I would just replace
them. Be sure and get net gaskets. About a three hour job if you have a
swing radiator.
- Chuck Wheeler -
82 FC 31 SB
Fort Worth, TX
_____
From:
WanderlodgeForum@yahoogroups.com
[mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of pattypape
Sent: Friday, January 19, 2007 7:55 AM
To:
WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] Re: gauge readings 88 FC
Bruce,
The 3208 coolant temp. appears to be low, The coolant is really
effected by the ambient temp, speed, and hill climbing. It also takes
time to get up to a stable operating temp.
The thermostat opens at about 185*, Fan kicks on at 195*. These
events could be a more accurate indication of temp than the temp
gage. So, I would suggest running the 3208 hotter and faster to try
to determine if the thermostat is opening properly.
oil press. 70 This is good......
Rear axle temp 210 probably not accurate...
It could take a full hour of highway driving to reach a stable rear
axle running temp.
Our 88 rear axle reads about 170* also ambient temp effected
ZF temp 195
This is good and rises quickly to the yellow during use. 240/250*
Pyro 600 to 650 RPM 2000 (This is good)
I have seen 1000* and 13/14 boost.
You are correct the gages could be at least 10% off, if they are
functioning correctly.
My experience with our gages is as follows:
The temp gages are really important, the old sensors are not
accurate, and the sensors do not always match the gage, I changed
both the 3208 oil temp & the rear axle temp gages and matching
sensors to get more accurate readings.
Sensors need to be matched and purchased thru a Teleflex or Stuart
Warner gage distributor.
BB is not much help with these old sensors, although BB has a
reasonable price on the gages.
Volt meters are more accurate, that is why volts are posted to the
10th of a volt, such as 12.7, 13.7 etc. Amp meter accuracy is not
criticle, so reading like 25, 50,75 amps is normal.
The Onan oil pressure sensor seems to be a higher failure part than
the gage. I think this is because of lack of use of the internal
diaphram. I replaced the sensor on the Onan to get a more correct
reading, 30/60 psi.
I have not replaced the Onan temp, gage or sensor, But I know the
coolant reads about 20 degrees high.
Hope this helps,
Bill 88 FC
--- In WanderlodgeForum@
yahoogroups.com, "birdshill123"
wrote:
>
> The following are my readings at a constant 59 mph. flat country.
> Water temp. 170
> oil press. 70
> Rear axle temp 210
> ZF temp 195
> Pyro 600 to 650
> RPM 2000
> ambient temp was 55 to 60
> At ambient temp of 75 the water temp climbed to just over 175
> I do not trust any of the gauges. I used my infrared thermometer
on
> the diff. and it was 160 to 165 depending on where you read. At the
> sensor it was 160. I know that my gennie oil prssure is off by 15
lbs.
> as I tested it with a non electric hydraulic gauge. I noticed that
> when I am in the hills and the turbo kicks in the pyro temps can
climb
> to over 900. Boost is about 10 to 12. How does all of this look??
>
> Bruce 1988 FC35
> " LaReina Gitana"
> on the road in Mexico
>
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