Carbon build up on pistons
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Joined: Feb 2010
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Carbon build up on pistons
Just recently I was lucky enough to pick up a 350 short block and two heads for $140. Everything is in pretty decent shape and for the most part this engine looks like all it needs is a good cleaning, which brings me to the pistons. I dissembled the engine and I am trying to clean off the build up of carbon on the piston tops. Ive tried soaking them in degreaser and even mineral spirits. They look alot better but are still covered with stubborn carbon. Any body have any tips on how to remove all the lingering carbon?
Joined: Oct 2001
Posts: 12,214
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From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Carbon build up on pistons
This stuff is NASTY.
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From: Pennsylvania
Car: 1992 Camaro RS
Engine: Rebuilt 350 going in after paint
Transmission: WCT5, 7k & counting behind the 350
Axle/Gears: 4thgen disc rear w/ 3.73 Posi
Re: Carbon build up on pistons
When I cleaned the pistons during my last engine build, I used a wire wheel in my dremel. Just have be careful as it will scratch the surface of the pistons.
Thread Starter
Member
Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Hmmm Ive heard about that chem dip stuff, someone at my shop told me about that. Unfortunately being that my Camaro took a crap on me (that's the reason for the engine) I am going to have to walk to the commissary on base and pick up some oven cleaner. Darn
Joined: Oct 2001
Posts: 12,214
Likes: 1,140
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Carbon build up on pistons
Tip: the longer you let it soak without drying out, the better it all works.
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Joined: Jan 2009
Posts: 2,313
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From: belle fourche,s.d.
Car: '82 z28
Engine: L83 5.7
Transmission: 700r4-1985
Axle/Gears: 3.42 posi
Re: Carbon build up on pistons
same thing with the oven cleaner-i think i used EZ-off,took about 4 soak/spray off cycles to get the pistons clean as new.
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From: Sussex County, NJ
Car: 1994 Z28
Engine: 355 LT1
Transmission: T56
Axle/Gears: 3.42
Re: Carbon build up on pistons
Permatex Gasket Remover works on everything. It even makes oxidized aluminum manifolds look brand new.
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Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Damn, I never know so much stuff is good at removing carbon, thanks guys. Maybe I am also a little impatient, I'm sure this process takes time and alot of elbow grease.
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iTrader: (3)
Joined: Jun 2007
Posts: 2,359
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From: Pennsylvania
Car: 1992 Camaro RS
Engine: Rebuilt 350 going in after paint
Transmission: WCT5, 7k & counting behind the 350
Axle/Gears: 4thgen disc rear w/ 3.73 Posi
Thread Starter
Member
Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Thanks guys, ultimately I used oven cleaner to clean the pistons. Let them soak then used fine grain steel wool and finally rinsed them in water. I think I should be able to get away with this...
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From: Sanctuary state
Car: 67 ******mobile
Engine: 385 Solid roller
Transmission: T-56
Axle/Gears: 4.11
Re: Carbon build up on pistons
Thats fine what you got there.
Unless its totally disassembled I leave the carbon on. Free compression
Unless its totally disassembled I leave the carbon on. Free compression
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Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Not sure If it is mandatory to hot tank the block and clean it up...its not too bad
Joined: Oct 2001
Posts: 12,214
Likes: 1,140
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Carbon build up on pistons
Those chunks in the eyebrows will chip out with a small dull screwdriver.
Thread Starter
Member
Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Yeah I'm just trying to be careful with it so I don't scratch the head of the piston.
Joined: Oct 2001
Posts: 12,214
Likes: 1,140
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Carbon build up on pistons
As long as its just a very light scratch your ok. Its the skirts,ringlands you don't want to scratch.
Just don't gouge the krap out of it!
Just don't gouge the krap out of it!
Thread Starter
Member
Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Very true, the face of the piston isn't as load bearing as the skirts are....I think I'm gonna upload some more pictures..I'm trying to get this motor together correctly, but as cheap and quick as possible. I think I'm doing pretty well because I picked up the short block for $140 and the guy said it was rebuilt about 10,000 miles ago. Looks pretty new just has some grime on it.
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Joined: Jun 2007
Posts: 2,359
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From: Pennsylvania
Car: 1992 Camaro RS
Engine: Rebuilt 350 going in after paint
Transmission: WCT5, 7k & counting behind the 350
Axle/Gears: 4thgen disc rear w/ 3.73 Posi
Re: Carbon build up on pistons
Hot tanking isn't necessary if its not too gunked up. When I did mine, I just used a bunch of simple green to degrease the surfaces of it. Then I used my wife's Shark steam cleaner to get in the oil passages(boy, was she pissed when she found out!). I used a cheap set of round wire brushes in various sizes I picked up from Harbor Freight to make sure all the passages were clear, and a set of thread taps to chase all the old sealant out of the bolt threads. It's a very, very messy job.
Thread Starter
Member
Joined: Feb 2010
Posts: 108
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From: Dover AFB, Delaware
Car: 1986 Iroc-Z
Engine: 5.7
Transmission: 700r4
Axle/Gears: 3.23
Re: Carbon build up on pistons
Hmmm...I think Ill have to see what I'm working with. I live on base housing so I must be careful how much crap I blow areound the garage/driveway lol
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