Carbon cleaner?

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andyjf89
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Carbon cleaner?

Post by andyjf89 » 28/03/20 11:26

Hi!

So I performed a compression test on the 93T today with okay results, 185-195 across the board. That would suggest a carbon build up on pistons etc

Would anyone ever do a carbon clean using products or know of a way of cleaning the piston heads without taking the head off?

Thanks



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jimi
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Re: Carbon cleaner?

Post by jimi » 28/03/20 12:47

Suggests to me there's very little if anything wrong with it, the BGB spec is
Compression pressure 192 psi
Minimum pressure 156 psi
Difference between cylinders 14psi or less
put a little engine oil down the plug hole of the lowest cylinders and repeat the test, if it goes up it suggests worn rings. If it stays the same then it suggests valve seats or possibly head gasket.
Not sure I follow the carbon build up on pistons causing low compression reasoning ?
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Topic author
andyjf89
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Re: Carbon cleaner?

Post by andyjf89 » 28/03/20 13:18

Ahh perfect, I was under the impression from another forum post that 150 psi readings were deemed average but if not that is great news.

It was mentioned high carbon build up can be the cause of high readings too, not sure about the reasonings myself just what was said online.

Thanks for the post, much appreciated 😄

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