RE: 5K - engine warning system

["Paul C. Waterloo" <74543.407@compuserve.com>]

>I have an 88 100CD (5000) with a low oil pressure warning light
>that keeps coming on. There is nothing wrong with the engine, no
>oil leaks, no oil consumption (only done 90,000 miles). The oil
>pressure senders have been replaced. Oil and filter change has
>been done. Anybody got any ideas on:

>1. What the spurios low oil pressure signal is (only comes on at
>3000 RPM), 2. If no anwers to 1, how to disconnect the engine
>warning system.

My parents use to have a first generation 5000S (81 or something?) with the
five cylinder engine. They ended up having the same problem as you
described. It ended up being one of the main bearings had too large of a
clearance. I guess from wear. You can usually tell if this is the case when
the oil light comes on, if your foot is off the gas, give it a little gas
or vice-versa. If the light goes off, then you problably have a bearing
with a large clearance. What's happening is the crankshaft is then
thrusting or seating itself against the bearing, closing the large
clearance, restricting oil flow, causing oil pump pressure to increase. 

If this was the case, the only real cure is to rebuild the engine (probably
just lower end), depending on the car's shape and how bad you need it, you
might just want to ride it out, it might last a very long time.....

Paul

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Paul Waterloo
Brookfield, IL

91 200q

EMAIL: 74543.407@compuserve.com
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