Cleaning piston tops?

Toms-SC

Registered User
Have a tech question for the pros out there.

My car is coming apart again for the heads and cam install. Last time I noticed a fair amount of carbon build up on the piston tops. It was not a smooth build up either. Is there a way to clean them up?

Thanks
 
I used a brass bristle brush and my wife's vacuum cleaner, but don't tell my wife that.
Then again, maybe I should mention to her I need a shop-vac.
 
Read the label on a bottle of Seafaom---it actually cleans the carbon off the surface of the pistons while the engine is together----if you can spray it directly into the air path----like pull off the connector for the boost gauge and spray it in there while holding the engine at about 2000rpm then let it set for a couple hours and do it again----the pistons will be pretty darn clean when you pull the engine apart and anything that is left will be much easier to get off---definitely worth a 7 or 8 dollar investment.................Dan
 
Not interested in any snake oil that may or may not have side effects. I'm all about the elbow grease. :)
 
Engine degreaser and Scotch-Brite work well. I usually spray the degreaser off with brake cleaner and then scrub it to a shine with the Scotch-Brite.

Also, you can sand blast them with 120-grit aluminum oxide.
 
And this is how I do it :D :D Of course, there's more too it than just what the pictures illustrate. I drained the oil first, hosed off the lifters as well and then drained the water out... if the engine isn't run and you don't let it sit for a long period of time, it won't be a problem. Also, turn the crank, wipe each cylinder dry, repeat until no residue remains. :cool:
 
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Not interested in any snake oil that may or may not have side effects. I'm all about the elbow grease. :)

No skin off my nose---you asked. Never heard the slogan "Better living through chemistry?????? there are any number of ways to destroy a set of pistons--carry on................Dan
 
Have a tech question for the pros out there.

My car is coming apart again for the heads and cam install. Last time I noticed a fair amount of carbon build up on the piston tops. It was not a smooth build up either. Is there a way to clean them up?

Thanks


Cleaning piston tops

If there out of the engine and off the rods we do this all the time first take a putty nife scrape the carbon off not to dig into the aluminum while soaking them in a salvent bath. Than take a green scrub pad in salvent remove the rest easy and dont hit the ring lands or skurts
 
Since you won't be taking them out, this is one way of doing it.

First cut small strips of cardboard about 1/4 wide and stuff them down next to the piston. This will prevent large bits of trash from getting down beside the pistons. Then cover the lifter valley and other pistons so that you don't get junk in them.

Then with the piston at TDC scrape the carbon off with a good razor blade. This will get rid of most of it. Don't worry about scratching the pistons, you won't hurt them *but do be careful about the block deck and cylinder walls!*

Then I use a soft wire wheel on a drill to clean off most of the remainder. You won't get it all but don't worry about it. Use compressed air to blow away the dust and then remove the cardboard strips and blow out next to the rings. Rotate the motor around, wiping the walls with a clean rad until the piston doesn't leave traces of junk behind it.

When you are all done spray a little WD40 on the walls so they aren't dry before re-assembling.
 
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