kevincnc

Hey guys, it's been a while. My head gasket on the '89 finally deteriorated and started to leak. I brought the head to a local machine shop and they found a low spot where the leak was, so I paid $55 for him to take .004" off. I also paid $37.50 for a "Jet Wash" and I still have to clean carbon from around the valves. I let him know I wasn't happy and he said I could just scrape it with a screwdriver. What an idiot.

So my question is what's the easiest way to clean the carbon? I figure a plastic putty knife and brake cleaner. I didn't let him mess with the valves since it only has 44k miles. Will .004" affect compression enough to worry about? I'm guessing it won't.

Any advice would be appriciated.



Kevin

Techno Duck

Bring it to another machine shop and have it hot tanked and soda blasted if really bad. It will come out looking brand new. I would also have them check the cut milling job the first machine shop did.

V2Rocket

WD40 and green scotchbrite will take the carbon off pretty easily.

fortysixandtwo

Mechanically removing it will take a lot of effort and, depending on your tool of choice, you run the risk of gouging the metal. Instead, let chemicals do the work.

Now, just spraying a cleaner on and scrubbing is still going to require some effort to remove the carbon as you have to let the chemicals sit to do the work. Making puddles of the stuff will not work well either since it evaporates quickly, so here's what to do.

Get some carburetor cleaner, paper towels, 4 ziplock bags large enough to cover each of the combustion chambers, and some sand or dirt (without rocks).
Step 1: Fill the bags partially with sand and seal shut,
Step 2: Fold paper towels so they're about the size/shape of the combustion chambers and put in place. (tear them up into smaller pieces to get the right shape)
Step 3: Drench them in carburetor cleaner.
Step 4: Place bags of sand over paper towels ensuring to work it and ultimately the paper towels into every surface of the combustion chamber, and also verify it is making a good seal to prevent evaporation.
Step 5: Go about your life for day
Step 6: Remove bags and towels
Step 7: Use a brass brush to remove the now loosely adhered powder that use to be difficult to remove carbon.


I've done this on pistons and it worked great.
You'll want to plug the spark plug holes too, to prevent evaporation.

kevincnc

Thanks guys, I'll give the carb cleaner a try.

KevinGross

With the valves out of the head, I have used a wire wheel. If you want to do the job right, you should be cleaning more than just the valve faces.

kevincnc

I know and I'm not usually one to cut corners especially on this car, but like I said with only 44k original miles I'm not going to disturb the valves. The intake side is very clean internally and the exhaust isn't bad. Maybe I'll Seafoam once it's running again.