Hi,
Just done a comp test on my warm m20b25, the results were the same across all cylinders but seem quite high compared to what I have read elsewhere on t'interweb.
14 bar + on all cylinders (>200 PSI)
Thanks in advance
compression test results - seem high?
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Speedtouch
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They do indeed sound very high; normal pressures are around 175-190 psi.
Are you sure the gauge is calibrated, and which engine block do you have - 25 6E or 25 6K?
Are you sure the gauge is calibrated, and which engine block do you have - 25 6E or 25 6K?
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
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ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
well i have some quite bad oil leakage issues so high compression may be responsible.
Basically enough pressure to blow the filler cap off! Both oil breathers are clear so not sure where, why or how it is leaking oil but if I drive over 2k rpm it proper spooges oil from somewhere around the back of the block. Comp test was first point of call.
Basically enough pressure to blow the filler cap off! Both oil breathers are clear so not sure where, why or how it is leaking oil but if I drive over 2k rpm it proper spooges oil from somewhere around the back of the block. Comp test was first point of call.
Engine runs fine and oil goes everywhere its supposed to. None of the pathways are blocked and new oil is still nice and golden.
Only other thing I have changed is I rotated the oil filter housing to allow for tubular manifold, and removed the oil cooler. From research I understood that both of these are completely fine to do... Unless I maybe have restricted the oil channel into the filter housing somehow
Only other thing I have changed is I rotated the oil filter housing to allow for tubular manifold, and removed the oil cooler. From research I understood that both of these are completely fine to do... Unless I maybe have restricted the oil channel into the filter housing somehow
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Speedtouch
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What grade of engine oil did you use? It may be worth trying a thicker one - 20W50 was used back in the day, when these engines first came out.
Lighter grade modern stuff may be too thin and be the cause of the leakage on an older engine.
Lighter grade modern stuff may be too thin and be the cause of the leakage on an older engine.
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
Im on 10w40 semi-synth at the moment and that is what I have used since I owned the car.
I replaced the headgasket recently and did a complete top end rebuild and problems have only started since then.
I think oil is leaking from the rear crank seal area, but still no real clue as to the cause.
I replaced the headgasket recently and did a complete top end rebuild and problems have only started since then.
I think oil is leaking from the rear crank seal area, but still no real clue as to the cause.
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Speedtouch
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- Posts: 14024
- Joined: Tue Feb 14, 2006 11:00 pm
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///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421



