I was going around the engine and the first three cylinders read 130-135 PSI. Then I rattled the compression tester a bit hard and the needle fell off . I think it stayed on since 1985.. So I put the needle on at zero and did the compression on number 4. 60 PSI !!! I thought that was a bit low , so I went back and checked number 3 again. It came out as 65PSI ... Then I took the needle off the gauge, pressed the decompression button to zero the gauge this time, put the needle on at zero. Duh. Now it read 130 PSI on number 3 and number 4....
I dont panic any more. Just stop for a bit, think, start mentally ordering parts from wherever, backtrack, think.. Like the time when I opened the engine hatch to see chunk of magnesium sitting on the block, that led to the replacement engine on order before the bus got home... I realised that despite the engine bucking at mid revs (see posting elsewhere) , it was storming up hills and running well, and sometimes running perfectly all in the space of a minute... The compression difference was so big that it did not seem right after only 18000 miles... Also it happened after the third thrash along the M4 from Bristol in a few weeks, and the engine had got a lot hotter on the second of the three trips. So as I had just measured three cylinders, I just went back and measured two of them again.. proving that it was the gauge.
