[Old School Nut]

hello guys, been awhile since I posted... anyways I am building a "small" engine this time and have found damage on the forged crank, the engine is a big 2 cylinder Wisconsin engine with a wet clutch.

the problem is with the woodruff key, their is a lot of fretting damage on the taper that holds the flywheel and the woodruff key was pounded around quite a bit, and their is what looks like a very tiny crack appearing from one of the woodruff keys corners, (haven't magnafluxed her yet)

I would get a new crank but they are hard to find, I have a spare crank for the engine but it has the same exact problem, I figure that since the engine is now about 50 years old I might as well try fixing it by griding out the suspect areas and filling them with weld and then re-machining the taper (machining isn't an issue i can do that myself) my problem is what kind of rod or wire is the best for this application, its not a bearing journal but its on a stressed part of the crank and the welds need to be machined. any of you old timers that used to make stroker cranks by welding and offset grinding want to pitch in?

thanks!
-Leo-

[powerrodsmike]

I don't know about welding it, I'd probably try tig with some e70s6. Then try to keep it from cooling too fast. I wouldnt weld up too much, just enough to fill in the crack. There is probably a guy who has welded up a crank and knows for sure.

But wait,

here is another thing you might try, clean it up really good and put a new key and then locktite the sheet out of it. I used to have trouble with my shovel head harley, (another big wisconson twin), throwing off its clutch basket. (it is fun to reassemble a harley primary with a pair of vise grips on the side of the freeway)
That thing has the same assembly design, tapered shaft with a key. I got mine through another year. I used a big dollup of red locktite on the shaft, tightened the nut until I could hear it scream and never had another problem. And yes, I was able to take it apart last year when I had to get inthe tranny.
Hope this helps, mikey

[Rick WI]

Someone that does crank repair and grinding can fix that up for you.

[Old School Nut]

thanks for the reply guys..

Rick, your a local, you know any1 here in the Madison Janesville area who I can talk to about welding up the crank? I wouldnt mind welding it myself as I am a pretty good welder, and machining it, its just a matter of what rod to use and how to weld it, around, lengthwise... (i want to learn)

[jim..]

Preheat the area to be welded and weld it with 1/8 SUPERWELD high nickle stainless rod,use as low a heat setting as you can while still getting good penetration,then wrap with insulation to let cool very slowly,or if it will fit,put it directly into a hot oven,450 or so,and turn down the heat by 50 degrees every hour ubtil cool.

[Rick WI]

you can get it done at the shop here. I'll be there tomorrow in the afternoon doing a dyno break in and tune on a motor but call in the morning and ask for Jon, he's the owner. The number is 608-825-1060. The shop is right off Hwy 151 between Columbus and Sun Prarie. It's at the Hwy V intersection, where you turn to go to the Columbus Speedway. You can bring it in and Jon can take a look at it to verify if it can be fixed reliably. He can weld it up and regrind it on the crank grinder. The shop does a lot of work repairing stuff like this.

Jon is very good at it. Jon also runs the Applied Metals department at MACT in Madison, he teaches welding. He may be able to locate a crankshaft for you or have one at school. Long shot but maybe another route in case it can't be fixed for whatever reason.

[scrot]

Do you have to put the hub, or flywheel back on the same slot, or can you just machine another slot 180` on the other side of the crank?

[Old School Nut]

I cant do that as a woodruff key by nature already weakens the shaft (I hate woodruff keys) with that in mind, another woodruff key 180* from the damaged one would more than likely crack the shaft....