Oil Pressure Problems
04-06-2006, 12:53 AM
#16
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Had a similar problem with low oil pressure as the engine gets hot. Mine dipped below 2 bar at idle only after several autocross runs in a row. Otherwise the oil pressure drops to the normal 3 bar at idle.
When I changed oil I noticed it was very very thin, drained out like water. Was using Vavoline max life, went with Vavoline racing. Now it only drops to just above 2 bar when idling after working it really hard.
Mine has 15K on a rebuild done by the previous owner.
When I changed oil I noticed it was very very thin, drained out like water. Was using Vavoline max life, went with Vavoline racing. Now it only drops to just above 2 bar when idling after working it really hard.
Mine has 15K on a rebuild done by the previous owner.
04-06-2006, 01:07 PM
#17
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I have always used the Mahle oil filters. I've been using Castrol full-syntec 12-40 oil.
It has only started happening recently... the past month. I had to have the rod bearings ground and used larger bearings as a result.
It has only started happening recently... the past month. I had to have the rod bearings ground and used larger bearings as a result.
04-07-2006, 09:39 AM
#18
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Question – you said that it ran @ 3 bar while cruising (say 3krpm) and then went to 4.5 bar under load – is this still at the same RPM? If so I would guess that you have a worn thrust bearing surface.
The slow build up of oil pressure at start up does sound like a pick up leak issue (or any air leak on the pre pump oil path). You did use the locktite stuff on the crank girdle? Did the oil pump fit flush on the block?
Chris White
The slow build up of oil pressure at start up does sound like a pick up leak issue (or any air leak on the pre pump oil path). You did use the locktite stuff on the crank girdle? Did the oil pump fit flush on the block?
Chris White
04-07-2006, 10:09 AM
#19
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I did use the Loctite574 on the girdle and the oil pump did fit flush to the block. The oil pressure does raise with load while cruising. How easily should I be able to spin the oil pump in my hands? I remember having to use a little bit of effort to spin the pump by hand - should I have replaced it? Thanks for all of the help 
04-07-2006, 10:39 AM
#20
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The pump does not spin freely - so you are OK there. Pump failures are very rare (never seen one!). If you can vary the pressure by changing the load at the same RPM then the thrust bearing is the main culprit. Unfortunately that’s and engine out type fix…
Chris White
Chris White
04-10-2006, 01:04 AM
#22
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I decided to clean out my oiling system with B12 Chemtool for 5 mins at idle. After fresh oil and diving my car around I noticed something new/different - the oil pressure will drop to sub-par ratings ONLY if I come to an abrupt stop, but it will rebuild itself w/out me revving the motor. The more gentle of a stop, the less the pressure drops. My thought would be the oil pickup. Any ideas?
