Question about cleaning head mating surface

[Lunchbox88]

Im rebuilding the top end of my '79 GS850G, and just have a couple quick questions about cleaning the head. The head gasket material leftover on the head mating surface is being very stubborn. The most important thing I need to know is if there are areas that I should be very careful of when trying to clean the head. I know not to touch the valve seats but what about the combustion chamber edges? At my disposal is a brass brush, scotch-brite pads, carb dip, PB blaster, WD40, brake cleaner and engine de-greaser. Im just looking to avoid marring something that will cause a leak or loss in compression. Thanks.

 

[Agemax]

get your local machine shop to do the lightest skim they can do to ensure the mating surface is flat and level

 

[Dogma]

John Pearson (the drag engine builder most known for his crank work) taught me to use the green roloc wheel. It worked very well. It won't hurt the aluminum at all. Well, maybe if you hold it in one place for an hour. Pearson also told me not to bother planing the head, just clean it and put the engine back together. If you have evidence of warping, then you would obviously need to get it cut. Some people also like to see a perfectly smooth metal finish all the way across the head surface. It really only needs to be smooth in the sealing areas. Corrosion pitting in areas not around the cylinders and oil passages aren't really important.

 

[FiremanBob]

Gasket remover (a solvent in a spray can) will help, along with the brass brush. It's very strong stuff. Also acetone.

 

[Lunchbox88]

Wow thanks for the quick replies guys. Is it safe to scrub the edges of the combustion chamber (ie where the head gasket sit around the piston)?

I will look for those green roloc wheels and gasket remover tonight. Would the green roloc disks be at an automotive parts store or at a hardware store like lowes?

 

[FiremanBob]

Your brass brush, wielded by hand, will not hurt the aluminum. But if you were to use a power tool, it could.

 

[posplayr]

Soak I purple power; it will ease off most of the gasket and carbon

 

[Dogma]

Wow thanks for the quick replies guys. Is it safe to scrub the edges of the combustion chamber (ie where the head gasket sit around the piston)?

I will look for those green roloc wheels and gasket remover tonight. Would the green roloc disks be at an automotive parts store or at a hardware store like lowes?

I got my roloc wheel (a knockoff. Roloc is a brand name that refers to the quick change adapter) at Harbor Freight. I'm not sure if every parts or hardware store will have them. An auto parts store that has painting supplies should have them, I'd think. Anyhow, it's not the one that looks like sandpaper, but the one that looks like a plastic coral reef. This looks like the kit I got from HF (which I can't find anymore).

 

[JEEPRUSTY]

http://www.youtube.com/watch?v=U-a2fuFKDAk


WOW! them roloc wheels are impressive. This is the red one in action.
Um do not use the red one eh!

 

[chuck hahn]

Dont use the grinder abrasive ones in that video....who the heck would use that on an aluminum head!! Use the ones that look like a big round dish scrubbie disk.

 

[Nessism]

Last time I had a cylinder head skimmed the machinist told me he makes a lot of money fixing heads damaged by people using those Roloc abrasive pad things. If any of you guys choose to use them it's strongly advised to use the proper type for aluminum, and don't bare down too hard.

 

[Souske]

Always used red rolocs for cleaning off old gaskets. The trick is to keep it moving, and use a feather touch. The softer green one sound like just the ticket for soft aluminum.

Bet you will never use a razor blade again!

 

[JEEPRUSTY]

Perhaps the green is alos to harsh.
http://www.levineautoparts.com/3mrosucodibl1.html
is a softer 3M product.

Also there is a huge difference in knowing someone who has done it a lot does OK with the process.
You would be "learning" possibly the hard way on the only head you have.

Hom much would maching cost vs. the hassle of using the abrasive?

 

[Lunchbox88]

Thanks for all of the suggestions guys.

JEEPRUSTY, I see where you are coming from but where I am at down at school, there really aren't any reputable machine shops. I will just have to do my best to be careful, and hopefully I dont screw it up

 

[1_v8_merc]

Permatex makes a good gasket remover, in a tall black can.
It's usually hit or miss, seems hard to find sometimes.

Really nasty ****....you just sit and watch gaskets melt and bubble away.

 

[Dogma]

Good advice here on using the roloc. I should have mentioned it when I recommended them. Even with the green, if you stay in one place for too long you can begin to mark the aluminum. Learn the process in areas where it doesn't matter.