build up on pistons...

[Roque]

I was locating TDC through the spark plug hole and noticed how cruddy the top of my pistons are. Question is will the carbon build up affect my engine negatively? Just seeing it in there is bothering me, might be time for a top end rebuild.

 

[XSLeo]

Unless it's a 1/2 thick I wouldn't worry to much. Some carbon build up is normal. It happens when fuel burns.
Get it running and check the compression on a warm engine. If it is withinspecs then the build up is fine.
Leo

 

[Roque]

Cool. Thnx.