compression test

[mike37cdn]

did a compresston test on my engine i got 60 pounds on all four cylinders is this good for an a motor or what should it be close to its all stock

 

[Loyd Nix]

Perfect! In fact I will swap you even.

 

[Mitch//pa]

Perfect

 

[Dick Deegan]

Right on the money for a stock engine. Congratulations!!

 

[Peter J]

I got between 54 and 56 on mine and happy to get it. You've got a gooden!
Pete

 

[gtrob2003]

Thanks! I was looking for this info. Any good sites or simple steps to follow to do this test on mine? I'm kindda new at engine work. What would be good indicators of needing to do this test/indicators of low compression? Thanks!

 

[V4F]

hard starting , use of oil , a cyl fouling a plug , alot of blowby.......... steve

 

[Bruce Adams]

Thanks! I was looking for this info. Any good sites or simple steps to follow to do this test on mine? I'm kindda new at engine work. What would be good indicators of needing to do this test/indicators of low compression? Thanks!

Look in Les Andrews' MODEL A FORD TROUBLESHOOTING AND DIAGNOSIS book, (the third volume of his series), which gives a full page on how to perform a compression test on a Model A.

He says an "average" Model A engine should have from 55 to 70 psi.

 

[mike37cdn]

thanks guys i am going for a long drive justenjoying my 28 tudor

 

[bogdonj]

where in Ontario are you from Mike?

 

[Larry Brumfield]

did a compresston test on my engine i got 60 pounds on all four cylinders is this good for an a motor or what should it be close to its all stock

60 pounds is good compression for any stock Model A but it's not perfect as others have suggested. Perfect would be closer to 76 pounds. BUT, it's not going to happen unless you have a new old stock, never used original cam.

 

[Larry Brumfield]

Thanks! I was looking for this info. Any good sites or simple steps to follow to do this test on mine? I'm kindda new at engine work. What would be good indicators of needing to do this test/indicators of low compression? Thanks!

gtrob, you never know what you can find in the Fordbarn already thoroughly discussed. Click on the following and read post #4.

http://fordbarn.com/forum/showthread.php?t=4960&highlight=compression+test

Then just for the hell of it, click on the following and read the thread.

Predicting gauge pressure, perfect Model A

http://fordbarn.com/forum/showthread.php?t=4996&highlight=compression+test

 

[RichPA]

It's not so much the number(PSI) but the variance between cylinders. The number is greatly affected by temperature, oil on the piston rings, and the amount of carbon build up in the combustion chamber. If they are all within a few pounds of each other you are in great shape.