82-gs1100 piston cleaning

[eddiev]

Any advice on cleaning black carbon buildup on pistons. I don't want to go further than removing the head. The piston domes seem to have carbon flakey deposits. I was considering a brass wire brush attachment to my drill.
Thanks.
Eddie V

[SqDancerLynn1]

I would assume you are installing new rings ? Use one of the old rings to clean the ring grouves Use a plastic scraper on the piston tops- put a little carb cleaner on the top to soften the carbon. IT wouldn't take much to remove them, soak them in can of berymans carb cleaner MUCH safer MAKE sure to stuff rags into the crankcase to keep crap out

[Dink]

Unfortunately as you have already removed the head you NEED to also remove the cylinder block.
The cylinder head and block are clamped down together!! releasing the tension on the head, does exactly the same to the block. This leads to the seal on the base gasket of the cylinder block releasing, you must replace the base gasket and the four large o-rings around the cylinder sleeves or the engine will seep oil around the base gasket after re-assembly.
Whilst the block is off remove the pistons and wire brush them clean (brass wire wheel on a bench grinder is best)

Dink

[fgh]

With all due respect to the previous two posts I'm quite confident you can clean the piston tops and reassemble without problems. Use a soft bristle metal brush to clean the piston tops. There is a very real danger you could damage the rings, pistons and cylinders by allowing debris to get below the top of the piston and not get removed. Block the gap with thread, string or paper board. If you have a shop vac then use it to collect the debris as you clean and to clean the gap when done. After cleaning each piston crank the engine by hand to expose anyting that might have gotten below the piston top.

As far as the base gasket cylinder goes I've never seen one leak. Of all the GS's most of the leakage at the base of the cylinder comes from the cam chain tensioner or the head cover. I've removed and reinstalled several heads and never had a base gasket leak.

BE VERY CAREFUL TO MAKE SURE YOU LEAVE NOTHING BEHIND IN THE CYLINDERS!!!

[eddiev]

82-gs1100, engine rebuild

Thanks for all the responses. I became concerned of exactly what Dink mentioned when I realized there are no additional bolts holding down the block. Will the block just pull right off now? Won't the pistons just be dangling then? I imagine it's a real pain lining it all up again.

[fgh]

The cylinders will pull straight off. DON'T TAKE THEM OFF. There is a shoulder on the bottom of each one that fits into the block. It is machined to fit very snug. It would require a strong pull and same wiggling and maybe some very careful prying to get it started. Yes the pistons and connecting rods will just start flopping around. When you go to reinstall the cylinders you'll need to start the pistons and then tap the cylinder back down making sure the the rings compress properly back into the grooves.

If you're careful and patient you can get the job done. But I can guarantee you its a waste of time. I looked at the fiche for an 82 GS1100 EZ and there is a base gasket and o-ring (probably four but the fiche shows one). IF YOU DIDN'T ALREADY HAVE LEAKAGE THEN REMOVING THE HEAD WON'T CAUSE ONE TO START.

[eddiev]

Thanks again. I think I am leaning towards leaving the block on. I've had some leaks but the best I can see it's been from a broken bolt on the cam cover and the tach cable. My charging system crapped out when troubleshooting it at 5000rpm like the manual said (I wouldn't typically idle it that high), I noticed oil dripping from the bottom but couldn't really find the source. I decided at that point since it was going into the cooler weather anyway that I'd update to the electrex charging system and do a complete gasket job. So that's where I am. I just want to pull the oil pan now and then start reassembly. The dampness in my shed caused a rust film to appear on the cam lobes which I'm not happy about. I basically want to get this back together and running.
Thanks to everyone. I'll keep you posted as to my progress.
Eddie V

[Guyver]

This helped me as well...

Thanks for the info FGH, I have a head gasket that started blowing oil in the front middle and I'm going to be doing the same thing soon. Warning Impending Thread Highjack: The bike has 29k on it and runs strong, should I bother with replacing the rings at this point? Also, in order to do this job is hanging the cam chain on a wire hanger the best way to keep it from dropping in the case? ~Gene

[Kcwiro]

....Also, in order to do this job is hanging the cam chain on a wire hanger the best way to keep it from dropping in the case? ~Gene

My friend and I used string secured to the frame of the bike somewhere. make sure you tie around the chain entirely since if you just wrap around it like me it will try and slip out on you. Then as you take each piece off *extra hands help* just grab the chain and re-tie it off until you get down to where your going to stop.

[crag antler]

Thanks for the info FGH, I have a head gasket that started blowing oil in the front middle and I'm going to be doing the same thing soon. Warning Impending Thread Highjack: The bike has 29k on it and runs strong, should I bother with replacing the rings at this point? Also, in order to do this job is hanging the cam chain on a wire hanger the best way to keep it from dropping in the case? ~Gene

I have 41,000 on mine and never had an issue of burning oil or smoking but feel while I'm in there I might as well do the rings.
I used a wire to hold the cam chain up.