89 200TQ Oil Guage

["Small, Jason" <Jason.Small@valleylab.com>]

Date: Sun, 17 Jan 1999 20:09:32 -0600
From: ""P-O Selander (EUS)"" <EUSPOS@am1.ericsson.se>
Subject: 89 200TQ Oil Guage

P-O,
I am the one who wrote the following:

>Are we sure we don't have to worry?  My 89 100Q at startup pins the oil
pressure >gage past 5 bar.  After 2-5 minutes it drops to what I
consider normal operation of 2 >to 4 bar (dependent on RPM).  I have
always thought this was due to the oil >warming and its viscosity
lowering.  However, I found out two months ago (the hard >way) that my
100Q has an external oil cooler.  Bentley implies this is a feature
>reserved for the turbo engine.  I definitely have one, as my oil
cooler blew out and >had to be replaced.  Now I wonder if the initial
high oil pressure "reading" (key >word, Selander) is a result of the
oil cooler not opening until after warm-up.  Any >thoughts?

>>And, maybe I was a bit careless (sometimes you have to eat your words) when
>>saying ""not to worry"", but what I meant was that the high initial oil
>>pressure is very common and should ""normally"" not be a source of concern
if
>>it drops down to normal readings once engine has heated up and oil has
>>become ""fluid"".
>>
>>What happened to your car? Did the cooler burst?
>>
>>/// P-O

Driving down a Boulder street one rainy evening, my oil can picture
appeared on the multi-function display.  I was not terribly concerned as
this happens from time to time, especially within the first few minutes
of startup as with Pat Korach and maybe Scott Miller.  However, I always
glance at the gage to confirm that I have no reason for concern.  This
time, instead of my pressure reading normal to high, it was low and
dropping lower.  Of course I immediately pulled over and shut down the
engine.  Looking under the engine revealed a gushing wound from some
heretofore unnoticed shrouding in the front right area.  Lo and behold,
I do have an external oil cooler.  Bentley does not outright say the NF
engine does not have an oil to air cooler, but in the diagrams, this
cooler is shown on the MC engine and not on the NF engine.  Apparently,
the cooler had burst from inside the finned area and needed replacement.

Now I am inclined to allow an extended warm-up time and I am even more
gentle with the throttle during the first five minutes of driving when
the oil pressure gage is above 5 bar.  Pat Korach, have you learned more
about the root causes of your oil pressure warnings?

Jason Small
Boulder, CO
1989 100Q