Compression test levels

[paulbaker1954]

Just been doing some more investigating on my odd sounding no 1 cylinder and decided to check compression. I am getting 135 psi on all 4 pots so no drastic difference on no 1 cylinder

That said are these readings a bit on the low side as the maintenance manual mention 177 psi

I should add that engine had a full rebuild 2k miles ago with new pistons and rings and I also regrouped all valves in etc

I should add that this was a “dry” test ie no oil put down bores etc

[hairygit]

Did you have the throttles wide open and a warm engine?

[paulbaker1954]

Did you have the throttles wide open and a warm engine?

Should have said
Throttles and choke open on cold engine, would a warm engine make that much difference