what to use to clean pistons in block.

[Swifty1638]

I actually hear that, atleast on a running car, to drain the oil out, pour in like 3 quarts of auto trans fluid, and 1 qt oil, run the car a few mins, then drain, fill with oil. ever see dirty gears in a tranny?

[deadeye]

^Ya, I have heard that too. I even think there was something on vfaq about doing that for lifters if I remember right. When I worked at oreillys, I heard of some shops even doing that on the down low once in a while too. They were always kind of hush hush about it though.

I never had the cojones to try that. Maybe worth a shot on a car that is going to be rebuilt soon, just to see if it works.

The wire wheel and brake cleaner are what I would be going for.

[Alpha D]

Hmm just the thread i was looking for! I have a question relatively the same....What about if the head is still on and you cant take the head of anytime soon is there anything that can be done. My Pistons are still pretty BLACK AND WET SINCE OF A SERIOUS RUNNING RICH ISSUE!! People told me carb cleaner and it should burn of but idk want to do anything stupid.

[Goat Blower]

Tranny fluid in the oil is a decades old trick, I actually just used that again recently with a light lifter tick sound, cleared it right up. Hydraulic fluid actually has cleansing properties hence the cleaning, but it won't do anything for dirty piston tops. Actually running ethanol fuels for the last couple of years has kept my tops perfectly clean, but simply leaning out your AF ratio for optimum power does almost the same thing. Piston tops get corroded from running rich like the factory tune.