Removing Carbon from Piston Tops

[Diabolic]

I tore the heads off my daily driver 95 Cobra last night for an upgraded setup. I noticed a 1.5" strip of carbon that goes from front to back across each piston. The carbon buildup is in the valve reliefs as well. The pistons are SRP Forged for inline valve heads. I'm installing some Vic Jr heads with 2.05 valves and some 1.7 Comp Pro Mag 1.7RR's. I don't want to experience any PTV issues due to excessive carbon buildup. Soooooooooo...............SHould I just throw it back together and Seafoam it afterwards, or should I try and scrape it off now? I'm thinking about soaking some rags in Trans Fluis and laying them across the pistons to soak for a day. Then I can use a brass wire brush on a drill to remove the carbon. Thoughts??? Seafoam would definately be easier, but I just don't know if it can remove a 1/16" of carbon buildup. This is a 331 with 75,000 miles.

[white88]

A wire brush on the end of a drill works well, just bring each piston to TDC before you start going to town on it.

[majorownage]

I wouldn't mess with it...It'll just make it pretty looking.

[shumpertdavid]

I roll the piston to tdc and use a scraper to take off the big stuff then hit them with a fine wire brush on my angle head die grinder

[Diabolic]

Could I leave the piston down in the bore about 1/4-1/2" and coat the top portion with grease of something? Then I can push the piston to the top and catch all the debris in the grease. When the piston drops I could then wipe the grease out????? I don't think grease would really hurt anything, but maybe WD40 would work better?

[sspstang]

A wire brush on the end of a drill works well, just bring each piston to TDC before you start going to town on it.

Correct sir, I have done it this way several times.

[BlueCoupeRedVert]

Small wire wheel in a die grinder. Then hit with a scotch brite pad mounted in a cut off wheel post. Cleans/polishes them nice'n purdy.

[Big Thumper]

I'd leave it, thats compression which equals HP

[shumpertdavid]

grease shouldn't be needed, just blow the cylinders clean after you finish and rub a light coat of oil on the walls.

[greenbullitt]

soak in motorcraft pm3, will wipe right off afterwards. wire brushing pistons is not recommended.PERIOD.

edit...still in engine, scotchbrite is your best bet,but why...my .02 focus on the gasket surfaces instead

[Alvarado GT]

I have heard of people using oven cleaner to get pistons clean

[Diabolic]

What is PM3? Where do I buy it? I have rags soaked in Trans fluid sitting on top of the pistons at the moment. I have a coarse nylon stripping brush for my drill. I figure nylon cant hurt it. I have a carbon scraper blade to try as well on the thick areas. Hopefully tomorrow when I get to work on it the trans fluid will have the carbon softened.

[greenbullitt]

pm3 is a motorcraft pt #, get it at any ford dealer or chandlers. It cuts carbon like you wouldnt imagine.The 3m nylon gasket removers (titty brushes) are nice.

[Diabolic]

This one isn't a 3M but it looks like a regular wire brush just it's nylon instead. Very stiff nylon at that. I may swing by the parts department and buy some of that stuff. Do they sell it to the public?

[greenbullitt]

This one isn't a 3M but it looks like a regular wire brush just it's nylon instead. Very stiff nylon at that. I may swing by the parts department and buy some of that stuff. Do they sell it to the public?

thats the brush I speak of. Yes they do. depending on the dealer, I may be able to recommend a contact