Slash five head gasket leak

[gspd]

Has anyone tried welding and re-drilling and tapping stripped stud holes?

You'd have to weld it up with the same aluminum alloy that the case is made of, so at best, the threads would be as weak as the original ones were.

[ME 109]

You'd have to weld it up with the same aluminum alloy that the case is made of, so at best, the threads would be as weak as the original ones were.

So......the coarser outside thread of a case saver is better anchored in the engine casing, and the case saver being steel is more capable of holding the load applied by torquing the engine stud.
So..........case savers would have been a better option from the factory?

[Major Softie]

So......the coarser outside thread of a case saver is better anchored in the engine casing, and the case saver being steel is more capable of holding the load applied by torquing the engine stud.
So..........case savers would have been a better option from the factory?

Yes.

But, the biggest improvement from any of the inserts is for repeated use. For original install, and fairly rare re-use, the factory design is usually adequate (barely), but, with a lot of these older bikes, those threads start getting a lot more action than they can really handle. Plus, it only takes one ham handed PO and they're toast. Steel on steel always handles a lot more repeated use.

[gspd]

So......the coarser outside thread of a case saver is better anchored in the engine casing, and the case saver being steel is more capable of holding the load applied by torquing the engine stud.
So..........case savers would have been a better option from the factory?

The factory only beat-tested these engines for 25 years.
I've been beating on them for 35 years.
A large/course thread will anchor itself a lot more solidly in aluminum than a smaller/finer one.
Case savers would have been a viable PERMANENT solution, but at a cost.
I doubt there were enough failures during the warranty period to warrant it.

I'd be curious as to what the Daytona winning mid 70's BMW were doing.

[ME 109]

I see plenty of 5083 aluminium plate being threaded for less demanding applications and 'rosan' inserts with locking ring for high torque apps.
The rosan inserts have coarse outside threads with a splined locking ring slide hammered into position.
Strong as.
Many of these inserts are being placed into 5183 weld metal.
(old insert cut out, weld up hole and macine, drill and tap for new insert)

I don't think our engine cases come anywhere near that grade tho'.

[Ross]

The case would need to be stripped right down. No crank or bearings. The casing then has to be heated up and then welded straight away. Big job.

[ME 109]

Keeping heat to a minimum is the first ideal.
Preheat will remove any moisture and will assist with fusion of the weld metal.
60 celsius is adequate for preheat, which can be kept fairly localised.
Having to open-up the stud hole at the top to allow access to the bottom of the hole would be necessary.
It is difficult to achieve good fusion of weld metal in a small parallel bore.
I think a successful process could be developed to allow welding with the engine internals in place.
Finishing/machining the weld back to level with the casing would require some thought.

Is it possible to stick a blob of 'putty' on the inside of the case when drilling and tapping for case savers, so as to 'catch' any swarf (chips) ?

[Frog]

I did a hard 500 miles this weekend with my stripped stud. Now I am ready to dig in

The rocker end play opened up...to become more noisy. The valve clearance opened up to about .010" and I readjusted mid-ride.

It was one of those rides that I did not want to miss...I will share some photos later.

[Frog]

http://picasaweb.google.com/blaisedesco ... directlink

[mattcfish]

http://picasaweb.google.com/blaisedesco ... directlink

Good times.
Thanks for sharing.