How do you prevent carbon from sliding past the piston head and grinding between the rings and cylinder walls?

I'm planning on removing the head and removing the carbon from the top of the pistons, but a buddy was saying that carbon can slide off the piston while it is being wiped down and tear up the cylinder walls causing excessive oil consumtion and blow by.

Is he right?

What's the best way to remove carbon from the piston heads while protecting the sides from tiny carbon chunks? (Keeping the stock pistons and rings only 15K miles).

 

remove the piston from the engine. this is the only safe way to do it.

 

I would advise not to do this unless you pull the pistons.

 

or you could just blow the sides around the pistons softly with an air gun. i dont see how the carbon would get past the first ring..

jmo.

 

It won't. For each piston, rotate the crank until it is flush with the deck before you clean. Instead of scraping the carbon off, use some carb cleaner (WalMart Hi Tech brand $1.17 a can) and a small wire brush to get the carbon off. Believe it or not, the carb cleaner and a towel will get quite a bit if it. This way you will more or less dissolve the carbon and not knock chunks off. Worked for me, discovered it by accident .

 

 

Gasket cleaner took it right off for me.

 

why must you do this? is there an ususual amount of buildup on the pistons? if it hasn't been running rich or burning oil there is nothing on those pistons that wont come right back in a few miles

 

A little carbon is normal and could even be argued is insulation keeping heat in the chamber where it can be used.

 

I'll be removing the heads over the holiday weekend and I'm expecting some carbon. I just wanted to keep it clean since carbon can absorb fuel droplets.

I don't want to pull the pistons since the rings are seated to the cylinder walls and I'd put new rings on to put them back in. If I was going that far then I would bore 030 over and get a good cross hatch.

Cleaning the piston head lightly with a solvent and a gentle brush could work. It would dissolve the carbon into smaller particles which may not get jammed.

 

You'll be surprised at the good cross hatch left. Every time I take a LT1 apart it always has a good cross hatch......high mileage or low mileage.

 

Shop vac.

 

Nuff said.

 

Thanks for the good feedback guys.

 

When I do this on 2-strokes, which is regular maintainence, I put a bit of grease in the gap around the piston first to catch the particles, then do the cleaning. Then I move the piston down a bit to leave the grease and crud visible so I can wipe it out. Next, I clean it up with a shop vac with 'interior detailing' attachments, which are small and really focus the vacuum well. I spray a small amount of brake cleaner around the piston to soften the grease up, then vacuum it out. DON'T do this with a flammable cleaner since it could blow up your vacuum! Finally, I apply oil, since the walls/rings are now degreased, and you don't want that.