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WERK I WERK I is offline
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Join Date: Jan 2003
Location: Wisconsin
Posts: 3,291
Originally Posted by JFairman View Post
Oil from the turbo drains to it's own little sump tank, then gets sucked to the turbo scavenge pump where it gets pumped on to the main oil tank without going through the oil filter, right?
Or does the oil from the scavenge pump get pushed through the oil filter? I think only the oil coming from the scavenge side of the engines oil pump goes through the oil filter.

So maybe this carbon thats clogging the spray bars is coming from coked or burnt oil from the turbo bearing.
Maybe this is more reason to use synthetic oil and let it idle cool down a minute or so after driving.

Might be a good idea to take off the turbo sump and see if you can rinse any little burnt oil carbon chunks out of it...
The turbo sump oil goes back into the oil tank unfiltered.
The main tank oil is filtered "before" it is fed to the engine on the pre-964 engines. The problem I see with their logic is when the engine is cold, the viscosity of the oil is high. The oil filters high a pressure spring bypass that allows the oil to go to the engine unfiltered, relatively speaking. Porsche found its wisdom later by filtering before AND after with the 964's.

The other problem I see is the top end lubrication is open loop. If in the unlikely event that any particles get up there, they have no where to go. A ticking time bomb, IMHO.
'85 930 Factory Special Wishes Flachbau
Werk I Zuffenhausen 3.3l/330BHP Engine with Sonderwunsch Cams, FabSpeed Headers, Kokeln IC, Twin Plugged Electromotive Crankfire, Tial Wastegate(0.8 Bar), K27 Hybrid Turbo, Ruf Twin-tip Muffler, Fikse FM-5's 8&10x17, 8:41 R&P

Last edited by WERK I; 10-07-2007 at 05:42 AM.. Reason: oops! meant open loop
Old 10-03-2007, 05:41 AM
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