Broken carb float bowl hole - argh!

I took my carbs off my SV to replace the main jets - but on unscrewing the float bowl this happened to one of the thread holes...



Arrggghhh!

I think it was a combination of using a impact driver to undo a seized original bolt and doing the screw up too tight last time i opened the carbs up. Lesson learned the hard way I guess...

i rejetted anyway and on putting the float bowl back the screw still tightens up ok to my relief. I put the carbs back in the bike and the screw/thread looks like this...



I've got a spare set of carbs which I'm attempting to clean up at the mo in case I'd need to replace them but it'll mean starting all over again with the rejet and there'll probably be other problems with the other ones to deal with too.

So my question is...

in the org's expert mechanical opinion would the original carbs with the broken thread stand up ok or would it have to be new carb time? I guess it'd be a case of try it and see although your help would make things clearer.

Cheers all!

[flymo]

does the threaded hole go right through? If so get yourself a longer screw and add a nyloc nut to the other end. Then leave it and ride.

So long as it does not leak you should be fine matey

[Sid Squid]

Never ever, ever use an impact driver on carbs. They are made of a light zinc alloy and are very soft.

As you've just found out.

I know... lesson learned the hard way I guess...

Yup, looking at my spare carbs the thread goes all the way through so I'll get a longer stainless bolt and nut sorted, that's a relief. Cheers loads Flymo!

Looks like the thread has gone on the hole now...tried another rejet last night and the bolt won't tighten down anymore

It was from me being an idiot and leaving the bolt as it was while out riding to test the jets. The bolt threads down into the hole ok, but keeps jumping out of the thread as it tightens...

Would the longer bolt and nyloc still work at this stage or would it have to be new carb time?

Cheers again everyone

[flymo]

Cant really see the damage that clearly in the photos. If there is room then a longer screw with a nyloc on the end should hold it all together just fine.

If its just the thread thats damaged then you could use a thread repair tool and replace it in situ without removing the carbs at all. Try Helicoil or Timesert type thread replacement kits.

edit: looking at the original photo again it looks like the part of the carb casing is snapped off in which case thread repair is going to be no good unless you can put the broken part back. Do you have the original piece that came off? If so you could use metal repair compound to build it up again and rethread the hole.

Personally I would remove it and replace the carb body if you have one in good condition.

[Sid Squid]

I'd try a longer screw and a nut - there's nothing to lose now, and it looks as though there should be enough material left for it to hold.

You'll know soon enough.