PDA

View Full Version : Removing carbon buildup from pistons, lands, and rings...what's the easiest?



rzimmerl
01-12-2009, 08:33 PM
I'm in process of refreshing a shortblock and the pistons have a small bit of carbon build up on them. Whats the easiest way to clean them? I've searched and came across a few like, soaking in kerosene, oven cleaner, and wire brush.

NEEDaSCbad
01-12-2009, 09:59 PM
what about hot tanking? it shouldn't cost much money to have them boiled. maybe 20 bucks.

rzimmerl
01-12-2009, 10:20 PM
Ya just thought about that. I have to pick up the block and crank from the shop tomorrow, might just see about dipping them also.

pablon2
01-12-2009, 11:20 PM
I'm cleaning piston crowns right now too. :) I use a brass wire wheel on a cordless drill.

NEEDaSCbad
01-13-2009, 01:23 AM
rzimmerl...you are getting set up with an AR correct? what kind of power are you estimating? I'm assuming around 340ish to the wheels, I'm probably way off
I'm curious as to what kind of fuel system you have to support it though.

Ddubb
01-13-2009, 01:30 AM
I use a piston ring groove cleaner tool for the ring grooves.

- Dan

rzimmerl
01-13-2009, 08:16 AM
rzimmerl...you are getting set up with an AR correct? what kind of power are you estimating? I'm assuming around 340ish to the wheels, I'm probably way off
I'm curious as to what kind of fuel system you have to support it though.

Yes, I have an AR. I am hoping for 350+ with the refreshed motor, ported heads, and cam. My member page is up to date so you can see what I will be running.

tim
01-21-2009, 01:41 AM
Believe it or not easy off oven cleaner. It comes it a spray.

rzimmerl
01-21-2009, 08:03 AM
I wish I would have tried the oven cleaner. The shop tanked them and "said" the rings broke when they tried to remove them to clean the ring grooves. Guess its time for new rings now.

XR7 Dave
01-21-2009, 09:47 AM
I wish I would have tried the oven cleaner. The shop tanked them and "said" the rings broke when they tried to remove them to clean the ring grooves. Guess its time for new rings now.

I'm wondering what they "tanked" them in because normal hot tank solution is completely incompatible with aluminum. We have a tank with carb solution which works fairly good to soften the carbon but you still have to scrape the grooves with an old broken ring or ring groove cleaning tool to get all the remaining carbon from the root of the grooves. You don't want ANY carbon left in the bottom of the grooves or you may end up with broken rings in the motor.

If the pistons are truly clean then you have on other issue to be concerned with and that is pin lubrication. The carb solution (or whatever they used to soak them in) will have removed all the oil from the pins and you'll need to work oil into them before re-assembly or you'll stick a pin in short order too.

I've pulled literally hundreds of rings out of old pistons and never broken one ever so I don't know why they would have broken these. Most likely they just tossed them in a bin while they were removing them and didn't want go looking around for them or else they broke them on purpose. Anyway, doesn't matter at this point.

rzimmerl
01-21-2009, 10:22 AM
They didn't use a dip tank, they used one of those heated rotary wash machines. There is still some crap in the oil ring groove even after "they used a ring groove cleaner", they scratched them with something maybe a pick since there is very small shiny grooves. The compression ring grooves look OK, but I'll use a flashlight tonite for a closer inspection. They did soak the pins with oil and the move freely. I am going to inspect them better tonite, and see how the grooves look. Probably still going to have use oven clean and then buy a scraper and redo it myself. This was the last time they will get any work from me.

Flex
01-25-2009, 08:44 PM
The best thing to remove carbon is an industrial paint stripper like TalStrip. It melts the carbon and it just washes away. Just wait for it to "cook" and hose it off with a pressure washer. Just don't get any on your skin.

DrFishbone
01-25-2009, 11:32 PM
I don't know how much the ring groove cleaner tool is...but I borrowed one and it made the job a ton easier...I cleaned as best I could dry, then sprayed out the little bit that was left with carb cleaner. I can't imagine how long it would've taken with anything else

XR7 Dave
01-26-2009, 12:15 AM
The heated pressure washers do not get the carbon off. Easiest thing to clean grooves with is a broken piston ring. It will get right to the bottom of the groove and won't damage the ring land. You'll have to turn it over and go both ways though because it's beveled on one side. Another big help I've found is to soak the whole mess in carb solution for a few days. Of course having a carb solution tank is a big plus. :) I just did this same job a couple weeks ago and it went pretty slick overall.

KMT
01-26-2009, 12:40 AM
Easiest?

New pistons & rings.

rzimmerl
01-26-2009, 08:21 AM
I have been squirting WD40 in the ring grooves for the past few days. I've used a ring groove cleaner and a pick to clean a couple of them. I think I might have some junk pistons with rings from a old parts car, I'll break a ring and use it also. They are turning out pretty good, a little wash of carb cleaner after takes the remaining residue off.

New pistons would have been nice, but not at this time in this engine. Thats for another TBD engine.