Cleaning top of pistons

[PCasil]

What do you guys' use/do to clean the top of your pistons without having to disassemble them? I heard people applying Mopar Combustion Cleaner on top of their pistons to get it quickly removed while others use rubbing alcohol, a rag, and some elbow grease to get it removed. I'm doing a headgasket replacement and found a little bit of carbon lying on the top of my pistons.

Besides that, as much as I want to remove the carbon, some people say just leave it on while others say clean it? Not sure what advice I should be leaning towards, I just want the best possible option for this before my headgasket comes in.

Thank you

-PCasil

[bmwstephen]

just buy your gasoline from a top tier gas station or run a bottle of techron. I know they seem like a gimmick but they do work. After a year of running, there's a noticeable difference in cleanliness

[bmwman91]

I had the same question / issue a few months ago when I got my head back from a rebuild. Here's my take on it:

- Since you are not removing pistons: You to NOT want to get carbon chunks (or anything else) between the pistons and cylinder walls or scoring could result. Have a friend hold a shop-vac hose next to where you are working to suck the debris out.
- I had pretty good results with a plastic putt knife and a steel gasket scraper (NOT a metal putty knife, a gasket scraper).
- Mineral spirits seemed to do a decent job of softening up the carbin build-up. Acetone worked well too, but it was a bit too smelly for me.

Scrape off as much crap as you can first. Then use a rag and some of the aforementioned solvents to get things shiny. You will also want to get the top of the block / deck VERY clean to get a functional HG seal. That is much more of a pain in the ass than the pistons IMO.

[jalopi]

Spray-9. You can find it in home depot for about $5-6 a bottle. Will dissolve any carbon buildup with almost no effort... cleaned many a piston / engine block / mating surface using this stuff. It's magic :D

Also, I'd use a tooth brush to scrub the carbon off - just make sure to let it sit for a few minutes.

On the other hand, when I was cleaning my pistons a few of my co-workers asked why I was doing it... removing that 'extra compression' they said :)

[PCasil]

just buy your gasoline from a top tier gas station or run a bottle of techron. I know they seem like a gimmick but they do work. After a year of running, there's a noticeable difference in cleanliness

I had the same question / issue a few months ago when I got my head back from a rebuild. Here's my take on it:

- Since you are not removing pistons: You to NOT want to get carbon chunks (or anything else) between the pistons and cylinder walls or scoring could result. Have a friend hold a shop-vac hose next to where you are working to suck the debris out.
- I had pretty good results with a plastic putt knife and a steel gasket scraper (NOT a metal putty knife, a gasket scraper).
- Mineral spirits seemed to do a decent job of softening up the carbin build-up. Acetone worked well too, but it was a bit too smelly for me.

Scrape off as much crap as you can first. Then use a rag and some of the aforementioned solvents to get things shiny. You will also want to get the top of the block / deck VERY clean to get a functional HG seal. That is much more of a pain in the ass than the pistons IMO.

Spray-9. You can find it in home depot for about $5-6 a bottle. Will dissolve any carbon buildup with almost no effort... cleaned many a piston / engine block / mating surface using this stuff. It's magic :D

Also, I'd use a tooth brush to scrub the carbon off - just make sure to let it sit for a few minutes.

On the other hand, when I was cleaning my pistons a few of my co-workers asked why I was doing it... removing that 'extra compression' they said :)

Thanks for your input guys! I guess I'll go right ahead and remove the carbon deposits on top of the pistons! Any more suggestions is helpful! Thank you!

-PCasil

[jrobie79]

I used purple power, soaked a rag in it overnight and put it on the pistons and the stuff just wiped off...be careful tho because PP will damage anything alumnium with significant exposure time.

[bddog]

Clean everything completely. Make it look like new. Rub some motor oil on your cylinder walls. Turn the motor over by hand. Remove the oil and debris that comes to the top of the cylinder.

[essi1553]

Easy off oven cleaner and a wire brush, instructions on page two, pictures post 1.

http://www.r3vlimited.com/board/showthread.php?t=299728

[PCasil]

Easy off oven cleaner and a wire brush, instructions on page two, pictures post 1.

http://www.r3vlimited.com/board/showthread.php?t=299728

Clean everything completely. Make it look like new. Rub some motor oil on your cylinder walls. Turn the motor over by hand. Remove the oil and debris that comes to the top of the cylinder.

Gotcha. Thanks guys advice, guys. I'll pick up a bottle of spray cleaner and get cleaning!

-PCasil

[AndrewBird]

A wire wheel in a drill works very well. Plastic scrub brushes in a drill work as well.

[jalopi]

Uh, wouldn't you be concerned about the wire wheel maybe catching the mounting surface for the head gasket? Sounds like that could be too much for aluminum pistons too... seems risky.

[PCasil]

Uh, wouldn't you be concerned about the wire wheel maybe catching the mounting surface for the head gasket? Sounds like that could be too much for aluminum pistons too... seems risky.

A wire wheel in a drill works very well. Plastic scrub brushes in a drill work as well.

S'all good. I was aware of using something hard to scrub the carbon deposits so I used a softer brush than a aluminum or brass brush.