cleaning suggestions

[geniusloerts]

HEY ALL,

Well I pulled the the head apart to replace the valve guide seals. I was wondering what is the best way to clean the carbon build-up off of the valves without damaging the valves. (my dad was ready to put them to the bench grinder wire wheel.....I told him to hold off.) If there are any suggestions and tips I am greatful!

Thanks,

-GeniusLoerts

[81xsproject]

carb cleaner...?

[geniusloerts]

I thought about that, but this is some serious build up. I will have to post some pictues, I belive it to be a record for the thickest build up on a valve, when it is thick than the valve.

[bikerphil]

I just replaced a valve on my 79F. While the head was off, I used a thin piece of metal with the end rounded off to scrape off the carbon. Just don't put too much pressure to avoid deep scratches. Lighter scratches are ok but don't scrape the valve seating area. I checked for leaks with gasoline, was ok, threw back togeather. 150psi each cylinder, runs like a champ.

[79XS11F]

I have done 3 head refurbs to date and I use a BRASS wire wheel. I have never has any issues with that and the job goes pretty fast if you have a bench mounted unit. In all three cases the valve to seat seal was perfect on the rebuilds.
Rob

[boyat68]

geniusloerts:

I spent a couple of years in my youth rebuilding small engines and was told by one of the manuals I used to use a 'Brass Wire wheel or brush" to remove the build up. (as suggested by 79XS11F) The brass being softer than the valve metal will not leave score marks that may cause problems. One caution, use a safety shield or safety goggles as the brass wheel sheds small pieces that will fly into your eyes, but that will do the trick.

[trbig]

Yup...brass wheel. Just be ready to blow some interesting stuff out of your nose from the carbon dust.


Tod

[geniusloerts]

Thanks guys,

Im going to go the brass wheel route. I learned the hard way about wire wheels and the flying bristles.(maginets are great) lets just say I will never leave my safty goggles off again, even for the smallest jobs.

[boyat68]

geniusloerts:

Another tip, A shotgun cleaning kit has a brass wire tip that can be used in an electric drill. This is great for cleaning out gunk in brake cylinders as well as any in place steel part. A cotton patch wrapped around the brass wire tip with a little mother's polish will give, a great finish.

[trbig]

To be honest, the bench grinder steel wheel would probably not hurt the valve unless you really TRIED to. A valve face is pretty hard, and the part that has the carbon on it isn't sliding up into the seal, so you won't get into that really either. BUT... the brass wheel is probably the safer way to do it. I used to use the steel wheel on auto valves all the time, but they were being turned afterwards.

If it is carboned up as bad as you say, you may pick up a few H/P after this since the motor will be breathing better. There also won't be as much weight for the springs to have to return to closed position, making their life easier. Also, the people that ride behind you AND the mosquitos will thank you..

Tod

[cloerts]

dad

I'm surprised dad didn't suggest the air chisle.

[geniusloerts]

Yeah, im sure it ran through his mind. Got the valve compressor , so the head should be starting to go back together.

[geniusloerts]

Welp, yesterday was a semi productive day. After painting for 20 hours strait, i returned home and cleaned the valves with the brass wire brush, lapped them, gave the head a bubble bath and a good scrub. The head ahas been re-assembled and put back on the bike. Just need to reinstall the cams now and she THE BLACK GOBLIN will be screaming again.


NOTE: When installing the springs and keepers, be certain not to ding the cylinders where the shim buckets inter, especially around where they first enter, makes for a big head ache. after fixing a nic or two, things are gooooooood

[prometheus578]

"Trick I learned..."

When installing the springs... first shove a standard sized business card into the valve well to protect the sides from gouges.

[trbig]

Just a tip... When lapping the valves, you will need to check valve clearances again. Even though I lapped mine very lightly last time, it changed my valve shims by 2 sizes on some of them.


Tod