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How to remove carbon buildup from piston tops.....

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So I have lots of thick carbon buildup on the tops of all my pistons. And I want to remove it. Can I ever so carefully use a razor to remove it or is that a no-no? If I were to slightly scratch the piston tops, can this be polished off or am I opening a can of worms. The Bentley shows this being done with a plastic scraper. This stuff is cooked on. Mostly from bad combustion related to a number of factors, all of which I hope I am addressing.
 
I like a rotary wire brush -- brass
Brush from the center off the edge
 
Soak the carbon build up with Sea Foam. This will soften the deposits then you can scrape off with a small putty knife. Do a good job with the clean up of the scrapings and you should be fine.
 
Re: How to remove carbon buildup from piston tops.

Bill
I will be doing mine tonight as my head is ready to put back on. My Triumph Maintenance book says to use a 'wooden' scraper about 1 inch wide. And says to leave a ring of carbon around the edge of the piston.
Regards
Craig
 
Re: How to remove carbon buildup from piston tops.

Yes, they are still in the block and no wooden spatula in the world will remove this stuff. I like the idea of the brass rotary wire brush. Any negatives here. The pistons are aluminum , aren't they? Scratch easily. AE pistons.
 
Re: How to remove carbon buildup from piston tops.

Is this in the engine, or out? It makes quite a difference.

In the engine, I run a bead of grease around the piston/wall joint to keep carbon out of there. Scrape the piston to the grease line. Then scrape the grease line. Though sometimes I leave about a 1/4" ring of carbon around the rim if I don't feel happy about working in that area.

Out of the engine, I scrape with abandon using my scraper. Sometimes I get inspired and use a carbon solvent, but not usually.
 
Re: How to remove carbon buildup from piston tops.

How about Easy Off Oven Cleaner, with Fox's bead of grease around the piston to wall area?
 
Re: How to remove carbon buildup from piston tops.

Bill
the carbon on my pistons is quite flaky and loose (lucky me).
Regards
Craig
 
Re: How to remove carbon buildup from piston tops.

Just throw a handful of buckshot on each piston when you put it back together. When you start it up the buckshot bouncing around will take care of any carbon. :savewave: :crazy:

For the not mechanically inclined, just kidding, do not do this.
 
Re: How to remove carbon buildup from piston tops.

tomshobby said:
Just throw a handful of buckshot on each piston when you put it back together. When you start it up the buckshot bouncing around will take care of any carbon. :savewave: :crazy:

For the not mechanically inclined, just kidding, do not do this.
Click to expand...


Actually, for a very brief moment I was thinking about that trick. I am gullible and weak at this time.
 
Re: How to remove carbon buildup from piston tops.

Nice comic relief there, Tom.
Foxtrapper addressed my concern about the debris.
From what I hear of your skill with dental instruments, this should come easy for you. ...
 
Re: How to remove carbon buildup from piston tops.

A bit of diesel applied with a paint brush usually loosens the carbon, if left to soak in for a while.

When decoking with the pistons in situ, an old vacuum cleaner is useful while chipping away with a paint scraper.

Finally any scraps in the gap down to the top ring can be lifted and vacuumed out using an old feeler guage with the tip cut to an angle.
 
Re: How to remove carbon buildup from piston tops.

Bill, just think of it as plaque and have at it....
 
Re: How to remove carbon buildup from piston tops.

TR6oldtimer said:
Bill, just think of it as plaque and have at it....
Click to expand...

Yeah but Ray, I think I am "out of network" and they won't pay.
 
Re: How to remove carbon buildup from piston tops.

Well, there's always the hygenist. But seriously, Dremel has a nice flexible cable drive outfit and a pretty good assortment of abrasives and wire brushes.
Just a thought.
 
Re: How to remove carbon buildup from piston tops.

I'd subcontract the carbon removal to someone experienced.
This lad looks like a winner to me AND he's wearing his
O.S.H.A. approved eye protection.

JackHammerweb.jpg
 
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