Cylinder Compression

[325_driver 422]

Hey, just did a rebuild

i suppose im asking this because im paranoid, as im not to flash with the mechanics of compression etc

every thing was done by the book, and the rings were definately for the engine etc etc.

The bore is still to specification

and the rings were as specification, no doubt

im concerned that when i put compressed air down the spark plug hole i can hear air leaking some where, and its not the valves, and its not out the head, definately not back out the spark plug hole. So that leaves the cylinder walls.

Head was Professionally Reconned, valves seated etc.

Its definately holding compression, but reason why i ask, is because, is it normal for some portion of air to leak down past the compression rings ? Obviously not a large ammount, but is this normal ?

Jono

[CamB 48]

Has it run yet?

[325_driver 422]

Has it run yet?

nah, put it all together and it didnt run because, 99% sure it was leaking through the valves, e.g. we did a s$$ job at re seating them, so i got the head professionally done.

basically im paranoid just thinking if it were possible to loose all that compression down the cylinder wall, but according to the engine re conditioners, they have never heard of a engine loosing 60 - 80 psi of cylinder compression through rings, even with a warped block from some one thouroughly abusing it

what you reakon ?

[*Glenn* 854]

Have you rechecked your valve clearances ?

To do a cylinder leak test, you must turn the engine over in the firing order (153624) so that both valves are closed to leak test each individual cylinder. This can be done with the rocker cover off so that you can see that both valves are closed and both rocker arms are on the back of the cam. This is also the position to check valve clearances which should be set at 10 thous. at the valve, not the camshaft.

[Guest FrantiC]

Run it in first then start to worry..