In trouble, cracked threads

[b12]

I've done something really stupid to my 2nd gen Bandit.  I have been working on getting it back on the road after years gathering dust  in my garage.  I cleaned the carbs, put on new discs  and pads, new tyres etc.  Today I put back on the old cover by the front sprocket/gearchange, after taking of a trick one I had put on years ago because the electronic speedo didn't work with it.  I used the bolts from the trick cover as the standard bolts have been lost (I'll probably find them next week).  

The bolts must have been longer because I have damaged the threads in one of the holes.  The thread has a cracked and it is now oil is leaking from the engine case.  I am hoping this can be welded, otherwise it'll mean getting other engine cases and stripping the engine and splitting the cases to replace them.  This is well above my skills level.

I've had a look and I think welding on the right hand side of the cracked thread looks like it won't  be a problem.  But on the left hand side there isn't much room, and I don't know if it's enough to get welded.

Has anyone experienced this problem before (I might be the first ham-fisted owner on this forum)? .  Can it be welded on the left hand side of the threads? 

Edited February 17 by b12

[TonyGee]

OOPS !!!!! yeah it can be welded 

[Gixer1460]

As said, welding not a problem if you get a GOOD welder - the hardest problem is getting the crack oil free, as heat from the weld will cause any oil to bubble out and contaminate the weld, might just have to give it a try!

[bunk]

36 minutes ago, Gixer1460 said:

- the hardest problem is getting the crack oil free

100% 

I would look at a different way of sealing it. Possibly coating a stud with sealant and threading it in, after thoroughly cleaning the affected area. As they say, it needs to be clean enough to eat off of.

If i was to get that welded by the AL welders i know,  it would be tear down time and haul the case half off to be cleaned at a shop.

[colinworth79]

As gixer1460 said above oil contaminated cases are tricky to weld . Personlly i would clean all the paint off around the area then die grind into the crack  .  I would remove the sump and gear change shaft and seal . Give it a good clean with some solvents .  Possibly giving it  warm up with a blow torch couple of time to get the oil to warm up and come out of the crack.   Put the gear change shaft back in when you get it welded .

Swapping the cases is not going to be econical by the time you get gaskets , bearings ect be better off getting another engine and stripping that one and selling the bits off .

[b12]

It's leaking oil out of the threads now as well. 

Thanks for the replies, because of them I'm kind of forming a plan that'll hopefully save the engine/bike:-  

-Take the sump off, (and maybe the gearshift shaft/seal).  Heat up the area to get the oil to boil/bubble out, then clean with solvents. 

-Grind the crack back a bit (with a dremel?), clean again and take it to a welder and get the crack welded.  

-Cut a stud to the right length coat it with sealant and screw it in.

 

Also I've got a couple of questions:-

-How do you  remove/replace the gear shaft.  I've never done it before.  Could I just leave the shaft in there and replace the seal after?

-What kind of solvent would you recommend for cleaning, would brake cleaner work?  

-What kind of sealant would be best for threading in the stud, would Loctite 577 work?

 

Thanks again for sharing your knowledge and the advise given.  I'll post some pictures of the job (if successful). 

 

 

 

 

 

[dupersunc]

To temove gear shaft, you need to remove the clutch and primary gear. Then remove the circlip in the picture above and tap the gear shaft out through the clutch side. 

To degrease, brake clean, then acetone before welding.

Edited February 18 by dupersunc

[clivegto]

Haynes manual is very useful if your not familiar with these engines. 

[b12]

Any recommendation for a good sealant for the stud?  I've just read that Loctite 577 is only good for a max temp of 150C°, will that be enough?

[Ivan]

Don't know if it's professional enough... but there is stuff, sounds like from a tell sell commercial... I thought put it on and forms one with the case.

 

I have no name or brand but mayby another knows what I mean?

 

[DAZ]

19 minutes ago, Ivan said:

Don't know if it's professional enough... but there is stuff, sounds like from a tell sell commercial... I thought put it on and forms one with the case.

 

I have no name or brand but mayby another knows what I mean?

 

Jb weld ? Or do you mean an epoxy type two part thing ?

[Ivan]

On 2/20/2024 at 9:06 PM, DAZ said:

Jb weld ? Or do you mean an epoxy type two part thing ?

I googled jb weld and exactly such thing I meant 

 

Quess there is no pressure on the oil at that point so mayby its worth a try?

[Gixer1460]

Just know that if you do use JB Weld and it doesn't work & you do have to get it welded, the job just became a whole lot harder, probably to the point of grinding the whole 'nub' off, back to clean metal and building it back up again, then drilling and tapping!

[Duckndive]

I,ve welded a similar area on GSX cases ....

Just remember to use files , dies wire brushes that have no been used on Steel in the past.....

after prep i cleaned it down with acetone and after it had dried / evaporated pre heated the area prior to welding ...

 

[b12]

So new files, brushes for cleaning and JB weld seems the way to go to use as a thread sealant for the stud after I get it welded.  I had a look on google and it's max temp is 260°C.

I started the job today.  I've removed the exhaust, sump, clutch side cover, clutch springs and plates.  I converted the clutch to a GSXR750  (2000-2004)  years ago because I wasn't a fan of the standard Bandit diaphragm spring one.  Problem is I can find a cheap clutch holder, and my old Bandit one won't fit.  I think I borrowed one from a mate when installing it.

In the UK they are cheaper (£18) but here in Belgium they are 42€ without post , and since Brexit it' not worth importing once the post and customs are paid.  I was thinking of buying a cheap aliexpress universal mole grip type?  Or can it removed/installed with an pneumatic impact driver?

Edited February 24 by b12

[Gixer1460]

Yeah a 'rattle gun' will shift it - hold the hub with a gloved hand ! At a push, even an impact driver (the type you whack with a lump hammer) may do it!

[Dezza]

I use the mole grip type and it's just ace. One of those 'wish I bought it 20 years ago' tools. It works on flywheels, clutches and gearbox sprockets too. I got it on eb@y about 5 years ago and I think it was about 15 quid.

[Duckndive]

36 minutes ago, b12 said:

So new files, brushes for cleaning and JB weld seems the way to go to use as a thread sealant for the stud after I get it welded.  I had a look on google and it's max temp is 260°C.

I started the job today.  I've removed the exhaust, sump, clutch side cover, clutch springs and plates.  I converted the clutch to a GSXR750  (2000-2004)  years ago because I wasn't a fan of the standard Bandit diaphragm spring one.  Problem is I can find a cheap clutch holder, and my old Bandit one won't fit.  I think I borrowed one from a mate when installing it.

In the UK they are cheaper (£18) but here in Belgium they are 42€ without post , and since Brexit it' not worth importing once the post and customs are paid.  I was thinking of buying a cheap aliexpress universal mole grip type?  Or can it removed/installed with an pneumatic impact driver?

You only need a couple off used steels and a length off flat bar to make one

no special skills just need a drill and a couple bolts ..

[b12]

I removed the clutch bolt  using a rattle gun, removed the gear shaft and heated the area with a small gas torch to burn the oil off, I then cleaned it off inside and out with brake cleaner.  I'm going to put it on my trailer and take it to the welder for further advice.

 

One thing that I noticed when looking in the engine from the clutch side is that there is blueing on the last crankshaft counterweight, and a slight bit on the face of the gear.  Is this normal?  I thought blueing came from getting too hot, the other visible crankshaft counter weight is the normal grey colour.  Should I be worried?

[Longhair]

The blue will be from the case Harding process. Don't  worry about it.

 

Edited March 31 by Longhair

[Fazz711]

Blueing is from the heat treatment to harden the teeth.