Compression test

[msmith]

I have no clue what I am doing, but having fun learning as I go. I am trying to get a plan together as to what I need to do to the Bronco vs what I want to do to it.

I am getting ready to remove the body so that I can clean the frame up and paint it. Figured I would do a compression check to see where the engine was as far as making my plans, ie. new/rebuild engine, or body work, or bite the bullet and do both which might upset the financial committe.

So, recommendations?

1 - 135 then 150 after a couple squirts of oil in the cylinder
2 - 155
3 - 142
4 - 142
5 - 128 then 150 after a couple squirts of oil in the cylinder
6 - 150
7 - 145
8 - 152

Plugs were clean and all looked the same

 

[Broncobowsher]

Put the plugs back in and run it.

 

[Rustytruck]

its common for 1 and 5 to be a little low on the small block ford. due to fuel wash on the rings. nose down attitude and fuel vapor boil over. you need to do nothing except stop fluid leaks.

 

[msmith]

Thank you, guys, for the information. I have learned today.

I was hoping for this. While I'd love to have more HP, I really didn't want to go down that road yet. I want to focus on the frame and body for now.

 

[Broncobowsher]

150ish is a good running motor. Smog era dogs are 120ish. Modern stuff tends to be 200ish. But 150ish is good regular fuel engine.

 

[DirtDonk]

And frankly, if this engine hasn’t run in a while, your compression numbers will probably go nowhere but up once it’s driven on a regular basis. Keep in the inside of the engine clean and getting good oil in there and even flushing it now and then it’s not a bad idea as long as you know there aren’t huge build ups of gummy deposits already there.

So, new oil and a good functioning PCV system and you’re in business.

 

[msmith]

Thanks everyone. I'm not real knowledgeable about motors so those two low cylinders concerned me some. Just learnin' as I go.

 

[Broncobowsher]

A lot of people wish there engine was as good as what you have. And are still driving them for many years.

 

[Steve83]

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