Carb boot mount broke off yamaha xj750

Hello,

When i was removing my 4 carb boots .. 4 bolts broke off
Drilled them out while still in my frame, installed helicoils on 3 of them. (they seem good but took days)
1 underside of a Mount broke off in the process.
I bought steel epoxy to put a bolt in but that melted yesterday when starting the engine.

What can i do at this point ?

The hole i drilled in the mount is not straight due to a bad position to drill.
There is still a drill bit inside and i seem to have such a hard time to drill that out.
Thats why i bought the steel epoxy weld thing. To just put a smaller bolt in it under a small 'angle'

I don't have aluminium welding equipment.
Is there a easy way to fix this with minimal costs ?
Could i dry alu welding with a torch ? Never done this before. Can i heat up the carb boot to 400°C , put the weld on and press a bolt in ?-> seems difficult cause the engine is in the frame and under an angle
Should i ask one of my friends with their decent welds ?
Should i use another metal putty that is more heat resistant?

 

Ouch.
You are going down a bad road.
Helicoils work but... They have to be accurate and basically I don't see anyway to fix your issues without pulling the head either way.
Once you have the head off, your options become simpler but you will need to put some money into it either way.
I think the JB weld stuff might work but you'd still be better off getting all those bolt holes repaired/helicoiled if necessary.

Or... Find a second hand... Head.

Sorry.

But, wait for other advice, I get a bit pendantic so there may be better options.

 

I already got 3 helicoils installed properly.
Its only the 4th one where i have a problem with.

Can someone confirm the engine is made of aluminium.
So then i probably also need an aluminium bolt to get it welded properly.
The helicoils are magnetic so also probably not a good fit with an alu-weld ?

 

I agree with everything suggested by @cds1984
In process of removing the head you might break exhaust studs which will cause similar problem anyway at some later date if you ever need to replace the exhaust.
Get the head repaired properly or find a replacement.

 

Further to this, if the one hole currently buggered needs to be weld repaired then re-tapped or heli-coiled, a replacement head might be the cheaper way to go.
You haven't stated the condition of this bike, to remove the head will require new head gasket, probably valve shims, new exhaust copper gaskets, good time to replace the valve cover gasket, maybe lap the valves, valve seals.
Things can quickly add up.

 

Newbie to the Forum here. I discovered a broken off- bolt while replacing the intake boots on my xj650. With a long list of things to accomplish; and a 2nd beater bike also waiting, I decided not to fret. A long self tapper and she's fixed. Aluminum drilled easily, screw is truly torqued down and sealed! I have sprayed around the boot gasket area while running, no vacuum leak. My opinion, move on to other repairs, you can always remove the head at a later date, and risk snapping an exhaust bolt.

 

I see your in the EU , you could remove the head and find a reputable machine shop and get it repaired properly. A word of advice always put anti sieze on the bolts when reinstalling bolts.

 

Last week that friend came by and he welded the broken mount. We made a new thread. Went fairly easy with everything still in my frame.
All carb boots are secured now !!
Made gaskets from cereal boxes and fired him up !
My bike really goes good now, no powerloss anymore in high revs. Did 150-160 km's/h in 4th gear.
This with pods instead of the stock air filter box !
So happy weeeeh

 

Gaskets from cereal box cardboard eh? Lifetime for those might be limited, even though cellulose doesn't dissolve with gasoline it won't stay in its shape that well. Still glad you got it sorted and running!