Depressing compression test results
#1
Racer
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I did a compression test the other day to get a baseline for the engine before I start any work. Here are the results (1-4) 140,120,72,106. With a little oil in the cylinders (1-4) 152,130,90,116. The test was done with the engine at operating temp, throttle wide open, all plugs out, freshly charged battery, cranking over a min. of 10 times per cylinder and Snap-On compression tester.
Obviously something going on in #3. The engine seemed to run fine. I have only had the car for 3 months and only put about 200 kms (120 Miles) on the car before storing it. It pulled 1.7 bar on the boost gauge and never made any strange noises. The engine has 212,000 kms (127,00 miles) on it.
Since #3 still didn't come up to snuff with the added oil, I'm thinking burnt valve?
Since I'm doing belts, seals water pump etc anyway, should I remove the head and check it and cyl. walls?
Any thoughts would be greatly appreciated.
Obviously something going on in #3. The engine seemed to run fine. I have only had the car for 3 months and only put about 200 kms (120 Miles) on the car before storing it. It pulled 1.7 bar on the boost gauge and never made any strange noises. The engine has 212,000 kms (127,00 miles) on it.
Since #3 still didn't come up to snuff with the added oil, I'm thinking burnt valve?
Since I'm doing belts, seals water pump etc anyway, should I remove the head and check it and cyl. walls?
Any thoughts would be greatly appreciated.
#3
Burning Brakes
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Try to do a leak down test and see if you can verify a burned or bent valve causing the problem. It also looks like you have a problem in #4 so taking the head off is a good first step, but first you may want to do a leak down. If it is a scored cylinder or bad rings then be prepared to do a full overhaul.
#4
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Leakdown test for the win. Do the test, and listen to where the leakage is coming from on cyl #3. From the tailpipe - exhaust valve. Out the throttle body - Intake valve. Dipstick tube/Oil filler - Rings.
#6
Racer
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I was afraid you were all going to say that. I was hoping to at least get one year of running under my belt before any major work.
I have never done a leak down test before and I couldn't find it on clarks. Is there a good site that describes the proceedure or could it be described here?
I have never done a leak down test before and I couldn't find it on clarks. Is there a good site that describes the proceedure or could it be described here?
#7
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http://www.carcraft.com/techarticles...ter/index.html
http://en.wikipedia.org/wiki/Leak-down_tester
For 1/2 hour charge, a local shop should be able to do it for you. You'd need a compressor and the tester to do it.
http://en.wikipedia.org/wiki/Leak-down_tester
For 1/2 hour charge, a local shop should be able to do it for you. You'd need a compressor and the tester to do it.
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#8
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again, I'd echo the recommendation of doing a leakdown and throw out that it could be the head gasket as cylinders #3 and 4 look pretty low even compared to #2, which tells me that it might be something common to both (which usually means head gasket).
A leakdown test will say for sure though
A leakdown test will say for sure though