Welding an engine case

[Adz478]

Hi guys, As you will see by the photos i have a broken mount on the Left hand side casing where the front sprocket cover mounts. The thread part of it is still attached so iam thinking of having it welded back on. My question is will the heat from the Aluminium welder effect my clutch bearings/seals and countershaft seal? Obviously it would be better to have the whole engine in bits, but the finances dont allow at this point. Any help is appreciated.

[dieselbeef]

thats  diff repair..i weld alum and that will be hard to fix..not imposs but tricky...it will need to be dont with the bike on its side..probly wont need to take it apart but fer sure youll be drilling and tapping the repaired hole...

i dont run a front sprkt cover...why bother

[Motoroost1]

I tig weld a fair amount of aluminum as well , and that part can certainly be repaired . However , to do it right , a fair amount of heat will go into that case and I doubt the seals will like it very much .

[cobbs]

I agree with motoroost to weld aluminum you have to get it really hot and I'm pretty sure you would be saying good buy to your seals and then would have to split the cases anyway so if I were you I would just leave it till you decide to to take it apart ,that's just one of the things you have to deal with on a regular baisis (vibrations braking things) my licences plate on mine broke off I still have half of it still bolted to my bike I've never seen a licence plate break that but that's what these big bikes like to do is vibrate and brake stuff

[Adz478]

Sounds like i will be leaving it until rebuild time, the only other concern was that if the bike ever threw a chain the aluminium spacer that sits underneath the sprocket cover will help protect the casing from damage. Without it, it could possibly smash the case to bits. A rare thing to happen, but i have seen it happen. Thanx everyone for your input.

[dieselbeef]

actually in my exp....i would run  and do run w/o the chain guide up front..the chain is less likely to bind up and usually they will run right thru instead of catching the case.

[awak100]

Could just grind it flat, and use a bushing as a fill in, to get it back out.  You said it still has threads in there.  Do that until you can fix it right. 

[RoostiusMaximus]

we've welded similar parts of bike cases before. we use a miller dynasty 350 and weldtech torch. In the time it took to type the question about doing it we'd have done it.

[cobbs]

at what cost though I garentee his seal would fail after that repair unless he split the cases which is what he's trying to avoid I've welded my fair share of aluminum even worked on aircraft parts and to weld aluminum as you should know you have to get it much hotter than a chromoly, stainless etc. I don't doubt you could fix that quickly and easily but the only way to fix it is to split the cases imo

[dieselbeef]

could cover that area with a frozen washcloth..and hope for the best..but in all likelyhood yer right...that shaft seal change w/o splitting it tho or it go in from the inside..never had one go bad...if its just the case halves id go for it

[RoostiusMaximus]

both the clutch rod seal and output shaft seal would be just fine, and if not theyre still a hell of a lot cheaper than splitting the cases.
you'd need to remove the ignition cover for access, thats all i'd further dissasemble.
like i said, if it was here it'd be done.

[Brute]

I was not going to weigh in on this, but here goes. As a long time AMT (Aircraft Mechanic Technician), and Tig, Mig, Oxy-Acetylene, Propane Air, Plastic, Spray Metal welder, What do you have to loose? Cover the seal areas with a wet rag and do a bead at a time. Heat the direct area with a hot air welder or heat gun before each bead, put a fresh wet rag on before each bead and if the seals go bad, change them. You MAY even be able to pull them OFF the bike and put a new seal on without splitting the case. Coat the seal with a thick layer of grease. After welding, if the grease has dribbled then you know it got fairly hot. Easy enough to look at the seal for signs of heat as well.

[kxpegger]

I haven't used this stuff myself but it does look interesting!

http://www.youtube.com/watch?v=jijW310xvp4&feature=related

[Brute]

I have a tube of those rods as well. Have had for a lot of years. If you use that you will have to remove more material when you go back to weld it up with aluminum rod.

[dieselbeef]

weld it with a stick rod and that case will be garbage