Bolt Snaped in Frame

[Gil]

Hello,

All was going too well, today I was about to drop the engine off my M600 FROM the frame, but the bolt on the left mount snapped in the frame:grump:!

So I think it's going to be tough to get it out now, don't fancy drilling, will mess the whole thing, and can't weld, so it's a job I don't want to take on, any suggestions.

[Murray Mint]

Can you not try an easy out?

[Gil]

Well won't be long enough to reach the thread, although I was thinking I could be "lucky" if bolt broke just in the engine case. it will just a matter of using the easy out when the engine will be off the frame.

The last mounting bolt could be an issue as it goes across the engine case, hope this one won't break, or round out!!!

[Flip]

Hmmm...there's a whole load of theories to this one on (stainless) steel screws into alloy engine cases and then people using copper grease to prevent them seizing which (possibly) has an adverse effect of actually assisting in Bi-metallic corrosion.

We did a whole load of experiments on this when I was at college with varying results but I digress.....

The long and short of it is that the bolt has to come out one way or another and then you have to deal with the aftermath once you have the motor separated from the frame.

If it screws into the engine itself then personally, I would definitely go for the drilling out method; 'carefully' drilling in the centre of the bolt with a Cobalt bit and going up in size until you can with crush the remainder of the bolt to break it free and then either use a thread repair tap or fit a Heli-coil to the case afterwards.

If it's a through bolt then surely you're halfway there and with a bit of penetrating oil or heat and a suitable drift and hammer just 'whack it out'?

I've had this problem on lots of engines where people have fitted stainless steel screws and not occasionally loosened and re-tightened them from time to time.

Be warned kids- stainless has a rubbish shear strength making it easy to break when un-doing but it's blooooody hard making drilling out a broken bolt/screw a task if not careful.

Have fun and good luck!!