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Re: How to remove carbon buildup from piston tops.
Easy-Off works. But it's MESSY. You have to plan ahead so it doesn't get down between piston and bore. I'd leave the "coke" in place and "burn" it off later with water. The stuff is carbon (think ~diamonds~ here) and any that gets down into the bore-to-piston area can chew things up kinda quick.
Just my superstition showing.
Easy-Off works. But it's MESSY. You have to plan ahead so it doesn't get down between piston and bore. I'd leave the "coke" in place and "burn" it off later with water. The stuff is carbon (think ~diamonds~ here) and any that gets down into the bore-to-piston area can chew things up kinda quick.
Just my superstition showing.
foxtrapper
Jedi Trainee
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Re: How to remove carbon buildup from piston tops.
Those bearings aren't aluminum. His pistons are. Oven cleaners can do nasty things to aluminum.conan69 said:
foxtrapper
Jedi Trainee
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Re: How to remove carbon buildup from piston tops.
Doesn't take three days for oven cleaner to do damage, it can start to happen in minutes. Considering how easy it is to scrape carbon off pistons by hand, I'd not bother with something that corrodes the piston.
BTW, as an ex jet mech myself, I find it fascinating that you've got a manual specifying the use of oven cleaner for a bearing. Who's?
conan69 said:
Doesn't take three days for oven cleaner to do damage, it can start to happen in minutes. Considering how easy it is to scrape carbon off pistons by hand, I'd not bother with something that corrodes the piston.
BTW, as an ex jet mech myself, I find it fascinating that you've got a manual specifying the use of oven cleaner for a bearing. Who's?
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Re: How to remove carbon buildup from piston tops.
Besides, racers pay big bucks to have thermal barrier (ceramic) coatings put on piston tops & combustion chamber surfaces to increase thermal efficiency of the engine. A light coating of carbon does much the same thing. Engines build more power AFTER a carbon coating has been established on the shiny surfaces.
An engine that is in good condition & tuned correctly will only build a light carbon coating. If there is excess carbon from previous conditions, it will burn off to the lighter level when everything is set up correctly. As Dr. E says, water injection with the engine running will hasten removal of any excess carbon.
D
I agree. Carbon is very abrasive. With the pistons in place, you can never keep some of it from getting into bore piston/ring areas when scraping. Better to leave it alone & remove it later, if needed, as Dr.E says.DrEntropy said:
Besides, racers pay big bucks to have thermal barrier (ceramic) coatings put on piston tops & combustion chamber surfaces to increase thermal efficiency of the engine. A light coating of carbon does much the same thing. Engines build more power AFTER a carbon coating has been established on the shiny surfaces.
An engine that is in good condition & tuned correctly will only build a light carbon coating. If there is excess carbon from previous conditions, it will burn off to the lighter level when everything is set up correctly. As Dr. E says, water injection with the engine running will hasten removal of any excess carbon.
D
Brosky
Great Pumpkin
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Re: How to remove carbon buildup from piston tops.
Dave,
You sound like you've seen the inside of a few good running engines......and maybe a few of some NOT so good running ones as well.
But I guess if they were good running, you wouldn't have seen the inside of them. Annyyyhow......
We used to de-carbon the Caddy HT4100 with the leaky intake manifold gaskets, by injecting water into the intake until it almost stalled the engine, then I'd shut the valve off and run WOT. Man, the stuff that came out of the tailpipes on those cars. Catalytic convertors weren't much good after that.
Of course, if we failed to remove the carbon, GM paid to tear it down properly and do it. No safety net here.
My advise is go very easy on the water injections. I had two go south on me and it wasn't pretty, even though I didn't have to pay for the damage.
Dave,
You sound like you've seen the inside of a few good running engines......and maybe a few of some NOT so good running ones as well.
But I guess if they were good running, you wouldn't have seen the inside of them. Annyyyhow......
We used to de-carbon the Caddy HT4100 with the leaky intake manifold gaskets, by injecting water into the intake until it almost stalled the engine, then I'd shut the valve off and run WOT. Man, the stuff that came out of the tailpipes on those cars. Catalytic convertors weren't much good after that.
Of course, if we failed to remove the carbon, GM paid to tear it down properly and do it. No safety net here.
My advise is go very easy on the water injections. I had two go south on me and it wasn't pretty, even though I didn't have to pay for the damage.
Got_All_4
Luke Skywalker
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Re: How to remove carbon buildup from piston tops.
After a professional carb rebuild the technician said I had a large carbon build up in my pistons in my TR3. He recommended pulling the head and scraping it off. I had no time because I was planning to take the car to the TRF party the next week. I had a similar problem in my Mercury Outboard where the piston rings were sticking. My Mercury dealer sold me a can Quick Silver carbon remover. You spray it into the carbs while the engine is running a few times and then stall it by over filling it. Let it sit and after start up man the black stuff that came out. Did it on the TR and it worked perfectly.
After a professional carb rebuild the technician said I had a large carbon build up in my pistons in my TR3. He recommended pulling the head and scraping it off. I had no time because I was planning to take the car to the TRF party the next week. I had a similar problem in my Mercury Outboard where the piston rings were sticking. My Mercury dealer sold me a can Quick Silver carbon remover. You spray it into the carbs while the engine is running a few times and then stall it by over filling it. Let it sit and after start up man the black stuff that came out. Did it on the TR and it worked perfectly.
OP
RonMacPherson
Guest
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Re: How to remove carbon buildup from piston tops.
Same procedure using GM Top End Cleaner. Then let it sit overnight for a good soak.
BMW, once upon a time, used crushed walnut shells as a media to remove carbon from the combustion chambers.
Same procedure using GM Top End Cleaner. Then let it sit overnight for a good soak.
BMW, once upon a time, used crushed walnut shells as a media to remove carbon from the combustion chambers.
AweMan
Jedi Knight
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Re: How to remove carbon buildup from piston tops.
Here is an interesting article on the topic on engine decorbonisation.
Engine Carbon Removal
Here is an interesting article on the topic on engine decorbonisation.
Engine Carbon Removal