Cleaning carbon from piston tops - any homebrew remedies?

nich · Post by **nich** » Mon Feb 09, 2009 10:38 pm

Do NOT use sodium hydroxide to clean aluminum. It is LYE which has been mentioned earlier is caustic and will destroy aluminum parts.

shoedoos · Post by **shoedoos** » Mon Feb 09, 2009 10:52 pm

Thanks Nich......lucky I asked.....

airflowdevelop · Post by **airflowdevelop** » Mon Feb 09, 2009 10:54 pm

Walnut shell mixture from SstrokerAce...

just did a set for a customer... Customer thought I bought him new pistons!

shoedoos · Post by **shoedoos** » Mon Feb 09, 2009 11:23 pm

Okay, I'll bite....what's the walnut shell mixture?

airflowdevelop · Post by **airflowdevelop** » Mon Feb 09, 2009 11:27 pm

shoedoos wrote:Okay, I'll bite....what's the walnut shell mixture?

Honestly... I don't know.

It is a mixture of different grit walnut shells... Bret would know for sure.

2.2=8 · Post by **2.2=8** » Mon Feb 09, 2009 11:30 pm

I discovered this by accident and have been using it for 25years to clean carbon from pistons........Permatex spray gasket remover. spray on carbon liberally, wait five minutes and gently scrub with small brass or stainless brush. softens carbon very fast, just wipe off with rag.

monstercutlass · Post by **monstercutlass** » Mon Feb 09, 2009 11:51 pm

go to any local heavy truck detailer and have them acidized.wont hurt the aluminum and only takes a few minutes to soak.its just a spray on solution.i just did a set for a friend of mine and they look new.

mike ramirez racing · Post by **mike ramirez racing** » Tue Feb 10, 2009 4:10 am

X2 on GM top engine cleaner. However its getting harder to get that stuff. I just used some on my pistons on my saturn. Let it sit over night and stuff wipes off with a rag in the morning.

I've also used purple power or Castrol super clean in my wash basin and hot water. Cleans parts nicely. I let stuff sit for a couple of hours and scrub away.

jeff swisher · Post by **jeff swisher** » Tue Feb 10, 2009 8:02 am

The first really high cranking pressure engine i slapped together got the full treatment of sharp edge removal...The pistons had carbon on the tops, but the rest of the piston was really clean..

non chemical
Frown if you want to, I went to the river and gathered 5 gallons of sand that was being blown across the top of the river banks..very fine sand

I taped my pistons and bagged the rods and more tape then with a siphon feed sand blaster(the 18$ cheap one) i blasted the tops of the pistons..It was slow due to the fine sand, maybe 1 minute or 1.5 minutes per piston

Then washed them off in the bath tub, hot water and dry....

To clean small parts like plugs and carbs i now use hot water and baking soda...

t3steve · Post by **t3steve** » Tue Feb 10, 2009 11:15 am

I've been told that reving the engine up and spraying water through the carb will clean the carbon off.
Has anyone heard or tried this?

DCal · Post by **DCal** » Tue Feb 10, 2009 11:22 am

I would be inclined to check the ring groove clearances before I went to all that trouble. If old and subjected to detonation, rich conditions, or bad seals they might not be worth the effort.
Dcal

mike ramirez racing · Post by **mike ramirez racing** » Tue Feb 10, 2009 2:44 pm

I think we can all agree bead blasting the pistons would be the best. He was looking for something easier. Not everybody has access to a bead blaster or can go out and buy one. Plus you have to make sure you tape the skirts and pin area well and after which you need to wash the parts again to get rid of the excess sand/glass beads.

Whitewater Racer · Post by **Whitewater Racer** » Tue Feb 10, 2009 2:51 pm

Its main ingredient is sodium hydroxide.

Some common cleaners contain Lye, which will attack Aluminum

Sodium Hydroxide (NaOH) is lye, also sometimes incorrectly called caustic soda. It is a VERY strong base. Strong bases attack aluminum. The interaction of aluminum and NaOH produces hydrogen gas. NaOH can cut the anodizing right off aluminum. It will make a polished surface cloudy and can lead to further degradation of the aluminum.

shoedoos · Post by **shoedoos** » Tue Feb 10, 2009 3:58 pm

Just to let you all know the result of using Lye (Sodium Hydroxide) was disasterous.....I was given a sample and used it on an old piston.

When I dropped the piston into the solution it bubbled and foamed like mad. It does strip the carbon off, but then it turns the piston black. Once it dried, the area dipped changed to a dark charcoal grey which looks permanent to me.

The whole process took about 20 minutes.

MadBill · Post by **MadBill** » Tue Feb 10, 2009 4:02 pm

Long, long ago, I left a cast iron motorcycle head to soak in a strong lye solution in an alumium pot. When I came back, the lye was everywhere but the pot was not...