Results of Compression test

[Afordman31]

I have a flathead that I took a compression test on, and these were the readings. Maybe someone could enlighten me as to my results. Is it a mixture of valves and rings or would the valves be the problem?

[Art Newland]

I'm no flathead expert but those numbers look pretty low any way you look at them. Probably going to need the works.

[super flat]

Your readings are pretty low. Has this engine been run lately? If not I would get it runing and recheck the compression much later. It won't be perfect but may improve. Gary

[JSeery]

The rise in the reading from dry to wet indicate leakage around the dry rings. As you can see, #1 and #2 as still very low wet. #1 I would think indicates a ring issue that is only partially helped by adding oil and #2 appears to have a problem other than rings that is accounting for the low reading. Was the testing done with the throttle blocked wide open?

[Ross F-1]

I'd guess valves aren't seating or are sticking.

[fordwife]

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Did you have a good battery that would spin the engine and did you run it at least three revolutions for each cylinder?

[Ole Don]

Often the reading will go up if the carb is held open. Like it says above, run the engine a while and run a test before it cools.

[Afordman31]

Thank all of you for your replies!

[Jack E/NJ]

Howzit run? Jack E/NJ

[jake197000]

has it been sitting for a long time.if so change oil and pull start it.had them come back to life more than once.

[Bruce Koukalaka]

Throw some Marvel Mystery oil down the cylinders and let it set a few hours, then fire it up (if it runs) run it for about 20 minutes then do another compression check, sounds to me like rings are stuck.

[alanwoodieman]

we on the ford barn are assuming that you have removed all the plugs, blocked the throttle all the way open and have a good battery, even a 12 volt to give it a good spin. if this is the case pour some MMO down the cylinders and let it soak for awhile, then before you try a compression test again pour some motor oil in the cylinders and give it a try. blown headgaskets usually level out compression between two cylinders, burnt/stuck valve will yield near zero, and stuck/dry rings will yield low readings. just did a test as outlined above on a 40 and got 120 plus

[Drbrown]

Like said .... Get it running for a while to loosen it up. Longer the better. MMO it. Then get a vac gauge hooked up to it. Should normally be 19 to 21 but down to 17 might be ok for a driver. Most important watch vac level and especially needle movement - that's going to tell you a lot about your valve and internal conditions i.e. bad gaskets etc