The infamous sump gasket

jetmechmarty said:

Hey Mick! Where ya been?

I’m going to try a Harley-Davidson fix. If it fails, I’m out nothing. I’ll post it up when I get to it.

Click to expand...

I am still here, well, without my XS, but you know Marty, once bitten by the bike you’ll forever love the bloody things....even if you have to tip them upside down to get to a sheared off bolt. I would also bet that the OEM bolts were soft as buggery, we had breaker plates in mechanical presses years ago just for the same purpose...to shear off before damaging the rest. Enjoying this thread as we’ve (well most of us) have has similar “issues” with that said bolt, you know the hard one to get to.......
So life in Tasmania is ok, cold after living in the tropics for over 25 years, we’ll go back North some day soon as we still have our home up on the big Island. I can also say the 270 degrees crank in the Triumph T120 does dampen the vibrations, 1200cc baby is also the way to go. When I get back up North I’ll buy / get another 650, have plenty of parts still at the shop and I really like the 76 model so that’s where I’ll be heading......

Quitting time!

Offending hardware on the lower left.

I do believe I’ll go to the hardware store and buy all new pan bolts before going through this again.

Looking at that got me thinking if one had this problem and needed a way to make drilling a hole in the center of that small screw a simple tool would be helpful. Having the hole perfectly centered and straight is very helpful.

For those here who have a lathe it would be a simple matter to turn down a steel rod to fit snug in the hole of the filter cover.
Then with this rod still chucked in the lath bore a hole in it using the size drill bit you are wanting to use for the easy-out.
I think I would make this bushing about twice as long as the thickness of the filter cover.
Then just bolt the cover back on with all the other good bolt holes and use the bushing to keep the drill bit centered on the broken bolt.

In a worst case scenario where while removing the broken bolt the threads are damaged beyond use this same method could be employed to guide the drill for a Heli-coil type repair. Might even pay to have a spare cover to keep as a tool for future problems!
One other advantage of doing this drilling with the filter cover installed is it would help keep drilling bits out of the motor.

A transfer punch could also work in a similar fashion

Beags64 said:

A transfer punch could also work in a similar fashion

Click to expand...

Yes, a transfer punch will get you a good starting point. The idea of the bushing would be to keep the drill bit from wandering off center. As bolts often snap on an angle even when starting on center a drill can walk off to one side.

Valid point. Maybe a set of bushings in common sizes, say M5-M10....?

Here is one option, however it is not metric. That long item over to the right would be used by bolting it to a good hole. Then one of the bushings would go in the round hole at the lower end in the picture to guide the drill bit. We used a tool very similar to this when replacing flywheel housings on large engines. You used a dial indicator to center up the housing then used this tool to guide the drill for the dowels that locked it in place.
https://www.browntool.com/Listview/tabid/344/CategoryID/210/Level/a/ProductID/3600/Default.aspx