welding crank case

Moshi said:

Does anybody have experience fixing things like that by welding? I have a guy here that's gonna weld it using argon welding.
Moshi

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Moshi.

I take it he is going to tig weld or heli-arc your case? If so, make sure the case is very clean. Clean it with a solvent and then clean the area to be welded with lacquer thinner or acetone. Take a rotary grinder and grind the area back to clean metal. On the crack, grind a vee about 3/4's of the way through the crack, then using filler rod, weld it back up. A 4043 filler rod works very well. If your welder is experienced with welding aluminum and doesn't use too much heat, there will be no problem with warping the cases.

After welding, use a rotary grinder or flat file to reshape the mating surfaces of the case at the weld. Or better yet, have them milled if you have access to a machine shop. Also, make sure the weld bead doesn't stick up too far inside the cases where the flywheels are. There is very little room between the flywheels and the case so, you may have to grind down the bead to clear the flywheels.

Good luck.