Mag housing

[Tractorman]

I am working on a Spanish LI 150 and the last person to remove the mag housing stripped one of the extractor holes. Most folk would repair this before re-assembly but not this hero they just banged it back together. Using my highly tuned agricultural skills I managed to get it off undamaged. I am undecided whether to tap the hole out to 7mm or drill a new hole near to it and tap to 6mm. Any thoughts on this?

[Tacolneston Nik]

Personally i would tap it out to keep it in the same position.

[Warkton Tornado No.1]

Like suggested, I'd use the existing hole centre & return it to M6.

Helicoiling would be my first choice, but there are any number of alternatives.

Incidentally, I usually modify the housing by utilising those two holes & attaching a simple jig strapped across to accurately add two additional small holes in line with the NU205/2205 bearing outer so that a pin punch can subsequently drift them out. That way a dedicated full bearing can be kept with a crankshaft should that be required in another block. It's not just a cost saving measure but time & risk as removal of the track from the crank needn't be done @ all then.

The two hole are subsequently plugged M4/M5 maximum with socket set screws, but they can also be used as a means of adding grease or, by leaving the top one out, a means of allowing excess out upon initial start up. I also make corresponding half moon cutouts in the sheetmatal spacer to allow for all of that.