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billjam billjam is offline
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Join Date: Aug 2007
Location: Perth, Western Australia
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I have now fitted my new turbo oil filter in the scavenge pump output line.


I fitted a 0-15 psi gauge on the inlet side of the filter so I could monitor the state of the filter. At idle, it shows about 1 psi. At about 4000 rpm it shows 1.5 psi when filter is clean (red line in pic). This is lower than I expected, but quite encouraging as it means the 100 micron filter has very low resistance to oil flow.
I have run it for a couple of days (about 50km) and there was no carbon collected (also encouraging).

I have also run the engine with the hose from the scavenge pump dumping into a container. At idle, it pumped about one litre per minute. This is also encouraging as it means no restriction in the oil system to and from the turbo - a potential cause of coking due to not enough flow.

I'll do another oil change soon and hopefully the problem is licked - or at least manageable.

Just another point of interest, the hose from the scavenge pump can be disconnected at the tank without having to drain the tank. It seems that even though the connection is at the bottom of the tank, there must be a pipe on the inside which goes up to a point above the normal oil level.
I'd love to see what's inside one of these if anyone's got photos.
1988 Carrera - 3.6 engine (with ITBs, COPs, MS3X) and a whole set of turbo body panels waiting in the attic.
Day job ...
Memories: '68 912, '72 911T, '80 911SC, '84 911, '85 930, '86 930, '87 911
Old 02-25-2009, 02:58 AM
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