Welding Crankshaft ?

I have a crank that needs welding up where Clutch gear rides . It needs to be built up approx. .040 and approx. 3/4 " wide. Any suggestions ? VKE Billet crank.
 
I have a crank that needs welding up where Clutch gear rides . It needs to be built up approx. .040 and approx. 3/4 " wide. Any suggestions ? VKE Billet crank.
Sure. Don't weld it up. Have the area machined down a little bit and press a bronze sleeve on it.....slot it for the gear retaining pin, and press the gear over that.
For years Briggs did that exact thing on one of their cranks, where the bearing pressed on.
I also have done that for 10 yrs. on a powerful Unlimited motor.....no problems whatever.
You REALLY don't want to weld that crank. The heat will de-temper it, and you'll basically have junk.
 
Thanks PD , but I'm not sure you are following what I'm saying. Crank is wore where Clutch rides on crank , not where Crank gear rides. It's a 4 disc Turbo Bully and directly under needle bearings in Clutch Gear is where my problem is. It's almost like Needle Bearing froze up or something and cut into crank , but Bearing is like new , rolls and spins fine. I have never run across this before. I will try and get some pictures today. I don't want to screw up Crank for sure!
 
If you think it would work without weakening the shaft I could turn it down on a lathe and make a SS bushing to take up the slack
 
needle bearings on a non hardened surface is a no no. you either need a hardened shaft, a hardened sleeve pressed over the shaft or a clutch with a hardened sleeve between bearing and crank. used to put needle bearings in standard bushing sidecovers and the only way to keep the crank from pitting in it was to press on a hardened sleeve over the crank.
 
IMHO, S.S. is not hard enough, you need Tool steel, hardened and drawn back to high 50 R., you might check with Torringtom needle bearings as to what and how to do it.
 
1 inch bully clutch

Looks like you're missing the inner sleeve part of the clutch. The bearing doesn't run directly on the shaft.

This is the way a 1 inch bully clutch is made. You have to keep this bearing and the flat Torrington thrust bearing well lubed with Vaseline.I relube them after every race. Also high clutch engagement and a lot of caution laps contributes to this wear
 
It's impossible to run the needle bearing on the crankshaft because keyway would destroy the needle bearing, no.2. The clutch hub has to go through needle bearing and slides over crankshaft. Now if your getting wear on crank your crank is to soft in that area or your clutch is spinning on crank.....
 
It's impossible to run the needle bearing on the crankshaft because keyway would destroy the needle bearing, no.2. The clutch hub has to go through needle bearing and slides over crankshaft. Now if your getting wear on crank your crank is to soft in that area or your clutch is spinning on crank.....

The Bully one inch four disc clutch comes with a special key that is cut round on the top where the bearing rides directly on the crank shaft,there is no sleeve like a 3/4 inch clutch.I have three of these running on 390 Hondas.I didn't say this is a good setup, but that is the way they are. Buller also makes this clutch in an outboard style that should solve this problem,but his third bearing would not work. On my 305 I ran a 3/4 inch clutch with a third bearing, so I would have the crank turned down to 3/4 inch and rekeyed.
 
I'd really hate to have to cut it down to 3/4 and loose all that meat on crankshaft. Just seem like it would make it weaker in the spot that it really needs to be strongest even with a 3rd bearing.
 
Roofer Dude I can weld and turn back to 1" radius if thats the path you choose. But you would be close to price of a new one. 200 will get it done. SVR
 
Find a shop near you or send it to one that repairs them ... Or you will be sorry. Pay me now or pay me later thing
 
Is welding and turning down the answer ? What if it were just turned down ? , will it last ? , will a 3 disc Clutch hold up ?
I built a 390 Honda and turned down the crank to 3/4 and ran a 3 disc Tomar with a third bearing,with no problems.Several others on Bobs said they did the same thing.If you do have it turned or ground down make sure they leave at least 1/8 inch radias where they stop the cut.
 
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