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a question about compression in PSI.

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Old Apr 11, 2015 | 07:31 PM
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Default a question about compression in PSI.

Just bought a new fancy digital compression tester and cold front cylinder is 139 and the rear is 150. Pretty close to whats acceptable but I will check the valves and make sure they are correct. When hot, what would be acceptable? 74 flh, New topend.

randy
 
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Old Apr 12, 2015 | 05:21 AM
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From: Rye, By God, Deep East Texas
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Every motor is different. The important thing is that the cylinders should be within 10% of each other. Yours falls in that spec. It is outlined in your factory service manual on how to do a proper compression check.
 
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Old Apr 12, 2015 | 07:37 AM
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From: la la land jerzey
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3 pumps on the gage is what we use with a small battery charger in place
 
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