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Discussion Starter #1 (Edited)
Quick question.

How thick is the washer underneath the oil pump pressure relief spring?

Mine is paper thin and wondering if this is factory spec or been replaced for the wrong one some time. (wouldn't surprise me with my car and it's shady history).

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Mine was too, when i replaced my snapped pick up thingy, i just put 2 in. I was told that although it is possible to increase the oil pressure by fitting a thicker washer, this could lead to other problems, like oil seals blowing, so i didn't put a thick one in. I was advised to try and increase flow rate instead.
 

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Discussion Starter #3 (Edited)
Yes too much spring pressure is not good. 87 psi is the max for these engines.

I'm thinking about the pressure asserted on the valve seat area in the closed position. If the spring had weakened or the washer is too thin then maybe oil could leak between this surface.

Look at the new valve I obtained from aflasud parts.
Much wider seat area.:)
Also old one was wobbly in the seat and also in the bore.
 

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I normally use a 1 or 1.5mm thick washer under the relief valve spring. Another trick to improve oil pressure to the crank without excessive pressure elsewhere is to put a restrictor in the oil pipes on each side of the block which feed the head. From memory, the standard hole is about 10mm diameter and I thread in a grub screw with a 3mm hole drilled in the centre.
You don't need a lot of oil flow to the head of a 8v boxer as it virtually sits in an oil bath anyway.
Sorry no pics of this.
MARK
 

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Discussion Starter #5 (Edited)
I normally use a 1 or 1.5mm thick washer under the relief valve spring. Another trick to improve oil pressure to the crank without excessive pressure elsewhere is to put a restrictor in the oil pipes on each side of the block which feed the head. From memory, the standard hole is about 10mm diameter and I thread in a grub screw with a 3mm hole drilled in the centre.
You don't need a lot of oil flow to the head of a 8v boxer as it virtually sits in an oil bath anyway.
Sorry no pics of this.
MARK
Thanks Mark.
The current washer is about 0.2mm thick by guessing. I will measure it later today.
Maybe I'll try using a 1mm one. The spring is old and I bet it has lost some of it's original tension.

: 0.50 mm to be exact.
Think I will stick with this one. I know the local suppliers here will never have such a precise thin wide washer.

Regarding altering the oil gallery diameter I wouldn't feel sure about doing something so drastic. I believe restricting the flow in the galleries would not be such a good idea as I have hydraulic tappets which need a good pressure (maybe with the mechanical tappets yes).
The hole through the head is about 3mm that feeds the tappets isn't it?
Unless there is another oil channel that flows into the head in addition to the 3mm one.




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Ah, yes. I had forgotten you had hydraulic tappets. I have only done this on engines with the mechanical ones. Probably best to leave the oilways alone.
 
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