Splitting the crankcase?

bennecc · Full Member Joined: May 31, 2009 Posts: 57

Anyone have any tips for getting this thing apart? I've removed all the nuts, and according to the manual I should be able to lift the top half off. It says to maybe use a rubber mallet to help get the two pieces loose, but so far that hasn't worked.

Every step of this tear-down so far has been much tougher that the manual makes it seem, probably something to do with the bike sitting outside uncovered for years. Anyways, the case doesn't even feel close to coming apart and I've been knocking it pretty good with a mallet. I really hesitate to hit it any harder.

Any ideas?

jayel · Posted: October 22, 2009, 3:42 pm Post subject: Re: Splitting the crankcase?

did you get the hidden nut behind the clutch? between crankshaft and clutch shaft above starter gear on clutch side, should have 18 nuts, count em'

bennecc · Full Member Joined: May 31, 2009 Posts: 57

yep, i got that one. 18 total.

xsjohn · Posted: October 22, 2009, 4:54 pm Post subject: Re: Splitting the crankcase?

Guys that use sealer on their head gaskets have trouble sometimes getting them loose........I suggested on another site to put the barrel and head in the oven at say 220 degrees and it came loose easily........don't know how you would ever get that thing in an oven but heat will help............. even in front of the oven would heat it like a huge turkey wrapping tin foil around it with the door off or above the door......think I'm loosing it again........ if the wife asks ...........your cooking....if the kid asks smack him.......

I have always used Indian Head shellac.on both surfaces.....never a leak or a problem with stuck case or cleanup..... ?

xsjohn

dwyatt · Posted: October 22, 2009, 5:28 pm Post subject: Re: Splitting the crankcase?

I'm a BFH kinda guy, always works.

yamaman · Posted: October 22, 2009, 6:12 pm Post subject: Re: Splitting the crankcase?

Heating aluminium with an oxy/acetylene torch can be risky - too much and the whole thing is toast!
If you use acetylene only to blacken the work area, then heat (with oxy/acetylene) only till black is gone, should keep aluminium safe.

Never tried it on cast, used it with success bending ali pipe & plate!

Any ali guru's there.................?

jeepurz · Posted: October 22, 2009, 6:53 pm Post subject: Re: Splitting the crankcase?

jayels right , hidden bolt

I flip motor and take bottom off JMO but I thinkits easier.

bennecc · Full Member Joined: May 31, 2009 Posts: 57

Yes, I got the hidden bolt. I've counted and between the regular nuts and the domed nuts I've removed 18 pieces altogether.

Is there possibly some kind of adhesive in there between the two halves?

I have no reason to believe that anything down there needs replacing, I more wanted to take it apart just to see what the innards are.

Also, a followup to my earlier statement about the difficulty of dismantling this thing so far: I just removed all the bolts holding on the plate which covers the starter gears (I'm guessing that's what's in there at least.....), and I still can't get that cover off. I've tried banging on it from every direction, including from the inside through the hold for the starter, and it won't move. I don't know, maybe it was just the effects of heat/cold/snow/rain etc for many years.

jayel · Posted: October 22, 2009, 8:48 pm Post subject: Re: Splitting the crankcase?

may be just hardened gasket goo if the bolts are all out of the starter gear plate and it's still stuck I'd suspicion somebodies been there before with perma-tex or something

bennecc · Full Member Joined: May 31, 2009 Posts: 57

Yea, that's kind of what I'm thinking. So any suggestions about what I can do about it? I'm starting to wonder if it's worth the trouble.

jayel · Posted: October 22, 2009, 10:09 pm Post subject: Re: Splitting the crankcase?

I'd try some heat, propane torch wouldn't get it as hot as oxy/acetylene and they are cheap, since it's already been disturbed it might leak if you just throw it back together, will need new seals ect.

xsjohn · Posted: October 22, 2009, 10:30 pm Post subject: Re: Splitting the crankcase?

Find a wooden box that will support the case.........put a single plate electric cooking burner in the bottom.........set the case above on the box and cover the engine cases with tin foil.......set on medium or so to start with and use a air conditioning temp guage poked through the tin foil above..........will take a while to warm the whole thing to 220 or so.............the case glue along with the cases needs to be warm when you knock the cases apart........

xsjohn

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