Morris Minor Owners Club

i think its the 3/8 drive not the half inch to undo drain bolt. although it was a loose fit.

racer
oil seals should not leak or i'll fail it at mot.
the oil comes out off a tiny hole near the backplate thus not going on to brake shoes.

Being a cheapskate, I got a big bolt and ground it down to have a square end that fits snugly (it also fits in the toolbox easier than a big blue Halfords multi tool). I actually did it for something on the Volvo a few years ago but wierdly it was the correct size for the Morris.
The socket square drive was a bit too sloppy so I didn't want to risk it.

brixtonmorris, 3/8 was far too small on mine... ('69) maybe mine aren't standard??

measured them at 11mm & 11.7mm so used an 11mm square

The multi-tool sounds like the one I have... it keeps slipping off. Most of the squares are too big, or far too long and tapered. Bit useless, really.
Either I can't get enough purchase on it, and I feel as though I'm lifting the car but to no avail (unlikely) or it slips off and cracks me on the head/arm/takes off three layers of skin &c...

Are the filler and drain plugs the same size? I can't compare them until I can get them off.... Heigh ho, at least I can check the gearbox easily!!

I might have a 3/8" drive and not the 1/2" ~ not too sure about that one (when am I ever??).

rays idea is good, you can hold the bolt in a vice across the flats to file , and then use the flats to undo

or use an angle grinder............

or use an angle grinder............

you must know me...

ive had enough of angle grinders,

No Ray, I just know what I would do......

3/8 was far too small on mine... ('69) maybe mine aren't standard??

Mine is a '69 2-door, a and a 3/8th drive fits perfectly! ... maybe its not the original diff?