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Piston cleaning without removing the heads

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Hi all,

I am currently working on a high performance engine and there is some carbon build up on the piston crown and I need suggestions to clean the carbon without disassembling the head, the easiest access currently is through injector hole.

Thanks for the help.


Live with it, or do the work. Engine disassembly is part of having a "high performance engine". There is no easy way to remove the carbon without leaving debris that may score the cylinder. That's why you remove the piston and heads to do that work.

Some light carbon on the top of the piston isn't that uncommon, but if it's bad enough you feel you need to clean it off, there may be another issue.

As David said, you really need to remove the head(s) to do it properly - and you can check for any other issues like worn valve guide, bore wear, carbon deposits on the valves, etc. Poor "tuning" with over-rich mixtures and/or retarded timing can also cause this - unfortunately most don't seem to realise stoic', or a little lean, is best for light running, with gradual enrichment as the loading increases.

There are products that are supposed to help clean the internals on a running engine, I think some sort of "Seafoam" is popular, but it's at your own risk.

This isn't on a direct injection engine, is it?

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