Well decided to do a compression test on warm engine before service and after. Run 3 tests on each cylinder as 1st one was always oddly low. Front shows 118-119 PSI while rear shows exactly 120 PSI. No idea if that is good or not as notes about it I had were on the old forum.
I also dropped oil, nothing on magnetic sump plug cool, however for the first time since I had transplanted bottom end I have removed the secondary filter accessed from the side. Wow. View attachment 6790
that's an ok-ish figure L - was that with throttle fully open? also, was engine turning over medium/quick? no point in commenting on debris - looks aluminium?
Throttle was fully closed should it be open during test? Engine was rotating medium but then it is how it always rotates. That bottom end is form a 900ss that snapped a belt and was used on track days. Slightly over half of the debris is rock and sand. Rest was alloy and bit of magnetic stuff.
Good result, for information, if you think your compression is low, you could try putting a small amount of engine oil in cylinders (5-10ml) giving it quick wind over and redo the test, if there is a significant change/improvement in pressure this indicates worn compression rings, if no improvement this usually indicates leaking valves, a leakage test would confirm this.
