compression test

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Mon 13 Sep 2004 14:33
compression test - Rosanbo
I did a compression test in Feb this year 1.3 petrol engine.

cylinder no & respective pressure reading (bar)


1 --- 17
2 --- 8, 10, 12, 13
3 --- 15
4 --- 16

I just did another one yesterday:

1 --- 17
2 --- 6, 8, 10, 11, 12, 13
3 --- 14
4 --- 15

cylinders 1 , 3 & 4 the readings given are based on 2 tests and both tests came with approximately the same reading, and the pressure built up fairly quickly.

Cylinder 2 is strange, on both occasions it starts out low for the first test and with each subsequent test the pressure gradually increased. Each test has the engine turning over for roughly the same time, and the meter reset each time. So there was no "same result" as per the other 3 cylinders.

I don't understand why the pressure is different with each subsequent test. I didn't put any oil in as I figured there was no point because the pressure was increasing anyway (with subsequent tests).

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Mon 13 Sep 2004 14:44
compression test - Dynamic Dave
Are you refering to your Mitsubishi Colt?

www.honestjohn.co.uk/forum/post/index.htm?t=19540

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Mon 13 Sep 2004 15:49
compression test - Peter D
I do not understand. How are you doing this test. Is this using a push and hold type compression tester and each time you get a seal you get a different reading or is it screwed in and you are spinning the engine over a few seconds for each test. Regards Peter
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Tue 14 Sep 2004 10:01
compression test - Claude
The cylinder walls or piston ring(s) are worn in cyl number 2. The more you spin the engine the more oil is distributed on the cylinder walls and hence makes a better seal.
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