Are these compression test results ok?

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NitroDann
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Re: Are these compression test results ok?

Postby NitroDann » Tue Sep 10, 2013 7:58 pm

The stronger it is the harder it turns the engine over the harder it pumps the compression gauge up.

Sorry If that came across aggressive.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

sticky nicky
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Re: Are these compression test results ok?

Postby sticky nicky » Tue Sep 10, 2013 8:03 pm

Ahhh ok, now I understand. No it didnt come across as agressive at all.

Appreciate your help.......again :D

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Re: Are these compression test results ok?

Postby NitroDann » Tue Sep 10, 2013 8:07 pm

There is a limit, and that limit is how powerful the starter motor can be.

Long story short the test needs to be done at operating temp, with a jumpstart to ensure the starter is going full power and with the throttle wide open to get all the air in you can.

If it wasnt done like that it doesnt count.

Dann
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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Are these compression test results ok?

Postby sailaholic » Tue Sep 10, 2013 9:41 pm

If the car want being run on a jump start the first time around, the performing the rest differently the second time around is likely to give different results.

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sticky nicky
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Re: Are these compression test results ok?

Postby sticky nicky » Thu Sep 19, 2013 4:35 pm

93_Clubman wrote:
sticky nicky wrote:I had a compression test today and they came in at 140, 143, 140 and 143.

Bit of a contrast from a year ago - hope it's just the tired battery!
sticky nicky wrote:Just had my replacement engine (1.6, long nose crankshaft) tested for compression before it goes in. Results were 225, 225, 225, 175.

viewtopic.php?t=54462&f=29


OK, so a got a new battery from RAC $235.00 :shock: have had another compression test done in the same conditions and its come up at 155, 157, 155, 157.

So I guess thats better, the mechanic did put a Cometic head gasket on as well but not sure of the thickness, so maybe thats a reason why its a bit lower as well.

The higher results (225, 225, 225, 175) were done when the engine was sitting in a trailer, so I gather you can get acurate results when its not cranking in your car?

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Re: Are these compression test results ok?

Postby NitroDann » Thu Sep 19, 2013 4:42 pm

Yes, either way its important that the engine have its throttle FULLY open.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.


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