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Ronnie's.930 Ronnie's.930 is offline
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Join Date: Nov 2007
Location: Rockwall, Texas
Posts: 8,765
Robby, the scavenge pump is mechanical, and it is driven off of the left camshaft via a small pin mounted through the tip of the pump's drive-gear axle. If the pin breaks, or gets severely worn, the pump will not work right or at all.

Like others have mentioned, you need to first test the scavenge pump's pumping capacity. If it is insufficient, you need to see if you have an air leak in the oil line leading from the turbo drip tank to the scavenge pump (an air leak allows the thing to suck air, and pump very little oil, and a tiny hole will not leak much oil even though it will allow enough air into the line to cause a problem when the car is running). If no leaks are found, you will need to remove and dismantle the scavenge pump and repair as needed).

If the flow test checks out OK, then exhaust gasses are getting past the turbo's axle seals and pumping air and oil out of the drip tank breather. This could have potentially been caused by damage to the turbine impeller and/or axle - by maybe a broken piece of air injector getting drawn into it (or hardened JB Weld).


Page 63 has an exploded-view drawing of the scavenge pump, and all of its parts and related hoses (the pump itself is item #31). See dude, I remembered you saying that you liked books with pics!!!!

http://www.porsche.com/all/media/pdf/originalparts/usa/911_USA_87_89_KATALOG.pdf

Last edited by Ronnie's.930; 05-29-2014 at 03:25 PM..
Old 05-29-2014, 02:47 PM
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