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billjam billjam is offline
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Join Date: Aug 2007
Location: Perth, Western Australia
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JF: I was looking at doing almost exactly the same thing but have now started on a slightly different approach.
I have just bought a similar filter by KRC Racing (does that mean I will be able to go faster?).
It is 100 micron fuel filter, 140mm long x 50mm diameter primarily designed for fuel injection systems. It has a long tubular stainless steel mesh filter.

I was going to fit it in the hose just before the tank as you did, but my current thinking is to fit it in the engine bay (I have lots of space) for several reasons.
1. Iím not sure how the extra weight hanging off this hose will work long-term.
2. If it is fitted down low, checking the filter will necessitate draining the tank or fitting a shut-off valve between filter and tank . As I intend to check this fairly often, this could be a hassle/more cost/more leak potential/disastrous if I forget to reopen the valve!
3. Iíd also like to fit a pressure gauge just before the filter. This will allow me to monitor the filter at a glance. I donít know what pressure I should expect here. It should be quite low, but for sure if it starts to increase, then I will have to check the filter internally.

I will mount it in the space behind my AC compressor in such a way that I can catch any split oil when I open it up.

JF and Dave: During my year-long rebuild of this car, the turbo sump tank and the main oil tank were fully flushed out and repainted. All rubber oil pressure lines were replaced and all other lines were properly cleaned out. All this coke has been created only over the past two months.
The K27 wasnít new, but it was completely stripped and rebuilt. The hot side and centre housing were sandblasted clean and were spotless when the parts went back together.

Charles: The idea of an electric pump sounds good. Iíd be interested in seeing any datasheets of suitable motor/pump combinations.

Today when I went out shopping for this filter at lunchtime, the temperature in Perth was 33*C (92*F). I left the car idling several times while I was in shops and each time when I came back (yes, it was still there!), the temp gauge had risen from mid-range (needle horizontal) to half way between horizontal and the upper red section. This sort of de-bunks the idle-down theory (which I donít necessarily disagree with) but when the car is idling, it gets hotter, not cooler!

I also had a chat with Shell this morning. It went along these lines Ö
BJ: explained problem, asked if this was normal, asked if there was a more suitable oil in their range.
Shell: Our oils donít do that. Must be from fuel contamination of oil. Click.

I guess fuel contamination is always a possibility, but with new or recond fuel system (fuel distributor, injectors, WUR) and AFRs mostly 12 to 13 through the range, I just canít see this being a factor.
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 02-22-2009, 09:11 PM
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