Low Compression on Cylinder 4 |
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Just can't stay away
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2012/5/20 22:28 From Parker, CO
Posts:
52
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I just finished a compression test on my 1946 Clipper.
The compression range was 70-85 PSI across all the cylinders except cylinder 4 was 45. When I put oil in the cylinders, compression went up to 85-90 across the cylinders but Cylinder 4 stayed at 45. My understanding is this points to a valve issue or head gasket. Is there anything I can try with the valves specific to this cylinder before ripping everything apart for a rebuild?
Posted on: 11/25 7:48:33
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Re: Low Compression on Cylinder 4 |
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Forum Ambassador
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2007/3/14 16:01 From New Jersey
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15715
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I'm assuming you have a 282 engine; make sure you have some valve lifter clearance on both valves. In other words, just make sure lifter adjustment isn't keeping a valve from closing completely.
That an adjacent cylinder doesn't also have low compression suggests (but doesn't prove) that it's a valve problem and not a headgasket issue. You could pressurize the cylinder with compressed air and listen carefully to identify where the loss is coming from.
Posted on: 11/25 9:58:49
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Re: Low Compression on Cylinder 4 |
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Just can't stay away
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2012/5/20 22:28 From Parker, CO
Posts:
52
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Thank You. That is the information I was looking for. I assisted with doing a valve job on this car with my Dad about 40 years ago. I am going to have to do a little research to remember the process, if the gap was set wrong back then, it was probably my fault.
Posted on: 11/26 14:26:18
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