1992 Force 150 compression minimum?

Gerard1970

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Hey guys, was wondering what the minimum compression on my 150 Force should be? 3 cylinders are 125 and 2 are 112. Is this ok? Thanks.
 

Frank Acampora

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Sounds a little low. I would expect around 145. However, it could be your gauge Try another gauge if you can borrow one. If the engine has not been run recently, run it for a little while before checking compression.
 

jerryjerry05

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I have twin 85's and if any of my cylinders(6) were 12# different I'd start looking for a reason.
You pull all the plugs when doing the test?
Let it spin up at least 5-6 times or more?
Like Frank suggested get a different gauge.
The comp with a good gauge is closer to 145-155

You can do a compression test without grounding the packs if you jump it at the solenoid.
 

Gerard1970

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When I did the test, I pulled all the plugs first...one thing I did not do was warm the engine up a bit first. It runs great, but just did a random test . Might have to try another gauge. Thanks again guys.
 

jerryjerry05

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No the test can be done on a hot or cold engine.
It can run good with different comp#s.
Some later model Forces actually were designed to have different comp on the top and bottom cyl. compared to the center holes.
After the test with a different gauge. Do a de-carb with Mercury's Powertune or BRP's Engine Cleaner.
 

Frank Acampora

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I didn't mean to warm-up the engine. If it had been sitting a good long while I meant you should run it for about 15 minutes to get some fresh oil into the cylinders and aid the seal.
 

Gerard1970

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Funny you said top and bottom cylinder ..those were the ones with lower compression. Thanks for the replies.
 
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