pulled the heads off a friends '72 last night....have a question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

superchevy · 08-22-2003, 01:01 PM

The valve seals were leaking oil into the cylinders pretty bad, so we pulled the heads off to have them rebuilt. The cylinders look pretty good, not much of a ridge - can still see a little crosshatch on the walls, so my buddy is just going to put the rebuilt heads back on.
The question is, there is a lot of carbon build-up on the piston tops from the oil burning; whats the best way to get this off the piston tops...scrape it? anybody use anything to maybe soften it up first?...wire brush?
Thanks, SC

cdowns · 08-22-2003, 01:36 PM

i've done it with a small wire wheel in a drill put the piston to the top of the bore spray alot of wd-40 and do the piston top, make sure to put rags in the adjacent cylinders and the valley to keep crap out spray lots of wd-40 while brushing and when done to flush the cylinders

junkyardjohn · 08-23-2003, 11:29 AM

I LIKE TO USE THE ROLOC DISCS THAT ARE MADE FOR GASKET REMOVAL. NOT!!!! THE FIBER ONES & NOT A WIRE WHEEL. I DON'T LIKE TO USE ANY ABRASIVE THAT WEARS INTO MICROSCOPIC PARTICALS, TO GET INTO PISTON RING GROOVES OR BEARINGS, CAUSING PREMATURE WEAR. I USE DIESEL FUEL AS A LUBRICANT TO LOOSEN UP THE CARBON BUILDUP. JOHN

LudwigTheMad · 08-23-2003, 12:38 PM

also...think about what you might be leaving in your engine if you use chemicals......

There is a substance called "marine" somthing or another....comes in a white metal container with a nickel size lid...heard this works fairly good.... its normally a crank case/ gas additive.

Warning to everone out there, I lost a 87 burb to this additive back in the early days. I bought the burb cheep and when I used this additive in the crank case.....it cleaned it so well I lost all the "leak seal" for the cooling system holding the coolent from entering into my cylanders (cracked heads...sealed with @$%#$% radiator leak stop.....)..

didn't know much of nothing about working on engines back then...........so I gave it away....

You guys would have loved it....it was "forest service" green..........

lukecp · 08-23-2003, 12:56 PM

I used carb cleaner to get off the carbon when i pulled my heads. It worked pretty good. Just use the little nozzle that comes with the can and blast the carbon right off. You don't have to get everything squeaky clean, just take off all of the thick stuff.

LudwigTheMad · 08-23-2003, 01:06 PM

thanks yellow 72....for stating in simple terms what I was trying to get across.............

to many people talking in my head today.....

Longhorn Man · 08-23-2003, 09:10 PM

And an oil chainge wouldn't be too bad an idea after spraying stuff and scraping things in the engine.
Maybe fire it up for a couple min to flush it all down, then drain it all out and don't forget the filter.

08-22-2003, 01:01 PM	#1
superchevy Got big-block? Join Date: Jul 2000 Location: Austin, Texas Posts: 2,453	pulled the heads off a friends '72 last night....have a question The valve seals were leaking oil into the cylinders pretty bad, so we pulled the heads off to have them rebuilt. The cylinders look pretty good, not much of a ridge - can still see a little crosshatch on the walls, so my buddy is just going to put the rebuilt heads back on. The question is, there is a lot of carbon build-up on the piston tops from the oil burning; whats the best way to get this off the piston tops...scrape it? anybody use anything to maybe soften it up first?...wire brush? Thanks, SC

08-22-2003, 01:36 PM	#2
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	i've done it with a small wire wheel in a drill put the piston to the top of the bore spray alot of wd-40 and do the piston top, make sure to put rags in the adjacent cylinders and the valley to keep crap out spray lots of wd-40 while brushing and when done to flush the cylinders __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

08-23-2003, 11:29 AM	#3
junkyardjohn Registered User Join Date: Aug 2001 Location: SOMERSET KY. Posts: 6,427	I LIKE TO USE THE ROLOC DISCS THAT ARE MADE FOR GASKET REMOVAL. NOT!!!! THE FIBER ONES & NOT A WIRE WHEEL. I DON'T LIKE TO USE ANY ABRASIVE THAT WEARS INTO MICROSCOPIC PARTICALS, TO GET INTO PISTON RING GROOVES OR BEARINGS, CAUSING PREMATURE WEAR. I USE DIESEL FUEL AS A LUBRICANT TO LOOSEN UP THE CARBON BUILDUP. JOHN __________________ junkyardjohn 69 1 TON TOW TRUCK // 84 4WD CUCV BLAZER// 85 1 TON 4WD STAKE TRUCK// 86 M1031 5/4 TON 4WD CUCV// ALOT OF OLD TRUCKS FOR ONE OLD MAN TO DRIVE. THERES ROOM FOR ALL OF GODS CREATURES RIGHT NEXT TO MY MASHED POTATOES// LIFE MEMBER OF P.E.T.A (PEOPLE EATING TASTY ANIMALS) DON'T RENT U-HAUL ALWAYS TELL THE TRUTH IT WILL AMAZE PART OF THE PEOPLE & ASTONISH THE REST

08-23-2003, 12:38 PM	#4
LudwigTheMad Registered User Join Date: May 2000 Location: Ramona, CA Posts: 2,033	also...think about what you might be leaving in your engine if you use chemicals...... There is a substance called "marine" somthing or another....comes in a white metal container with a nickel size lid...heard this works fairly good.... its normally a crank case/ gas additive. Warning to everone out there, I lost a 87 burb to this additive back in the early days. I bought the burb cheep and when I used this additive in the crank case.....it cleaned it so well I lost all the "leak seal" for the cooling system holding the coolent from entering into my cylanders (cracked heads...sealed with @$%#$% radiator leak stop.....).. didn't know much of nothing about working on engines back then...........so I gave it away.... You guys would have loved it....it was "forest service" green.......... __________________ That's right, I'm back in the game again. No it's not pink..... 1972 Blue and White Suburban.

08-23-2003, 12:56 PM	#5
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	I used carb cleaner to get off the carbon when i pulled my heads. It worked pretty good. Just use the little nozzle that comes with the can and blast the carbon right off. You don't have to get everything squeaky clean, just take off all of the thick stuff. __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

08-23-2003, 01:06 PM	#6
LudwigTheMad Registered User Join Date: May 2000 Location: Ramona, CA Posts: 2,033	thanks yellow 72....for stating in simple terms what I was trying to get across............. to many people talking in my head today..... __________________ That's right, I'm back in the game again. No it's not pink..... 1972 Blue and White Suburban.

08-23-2003, 09:10 PM	#7
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	And an oil chainge wouldn't be too bad an idea after spraying stuff and scraping things in the engine. Maybe fire it up for a couple min to flush it all down, then drain it all out and don't forget the filter.



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