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Castellated rear hub/drum nut on a '51/'52 MM
Posted: Tue Feb 23, 2016 7:48 pm
by 1970man
Hi all
I urgently need to find a replacement rear hub nut for my MM (early '52), it's for the nearside/passenger side (RHD UK car), with the lefthand thread.
Can anyone point me to a supplier for these castellated nuts? or alternatively a nut from another application, that will work to hold the rear drum assembly on?
thanks!
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 9:22 am
by smithskids
Check first if it is metric or unfor BSF. Any machine shop can make you one.or some one with a screw cutting lathe. Where abouts are you?
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 9:26 am
by 1970man
Hi, I'm in Cheshire.
thanks, RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 10:42 am
by smithskids
Axle thread will be 5/8" X14 BSF or 5/8" X18 unf Left hand and Right hand.
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 11:03 am
by DAVIDMCCULLOUGH
Leadbetters have this drum listed on ebay so may just have the nut as well, worth an email or phone call
http://www.ebay.co.uk/itm/MORRIS-MINOR- ... SwstxVVz9E
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 11:15 am
by 1970man

Thanks for the heads-up, I dropped them a line yesterday evening but no joy alas.
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 11:48 am
by mike.perry
The rear hub nut which secures the rear brake drum to the splined half shaft is a clockwise thread on both sides as the half shafts are interchangeable. The nut should be UNF thread but if the half shaft or axle have been changed it could be BSF.
The only anticlockwise thread is on the NSF stub axle.
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 11:58 am
by 1970man
mike.perry wrote:The rear hub nut which secures the rear brake drum to the splined half shaft is a clockwise thread on both sides as the half shafts are interchangeable. The nut should be UNF thread but if the half shaft or axle have been changed it could be BSF.
The only anticlockwise thread is on the NSF stub axle
Thanks, that might explain why it wasn't looking its best.
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 12:17 pm
by mike.perry
Please send me the details of your car for the register
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 5:42 pm
by 1970man
Hi again
The factory MM manual, in section H1 "removing and replacing brake drum and hub" (rear axle section), refers to the nuts on the end of the half-shafts being threaded lefthand on LHS of the car, and righthand on the RHS. This is what I've been using.
Maybe it changed during MM production? I'm new to these, so remain slightly confused (it doesn't take much!).
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 6:48 pm
by smithskids
In section H.1 Removing and replacing the brake-drum and hub. it states"remove the split pin from the axle nut and unscrew the nut with a set spanner, REMBERING that the axle half-shafts are threaded right-handed on both sides of the car and are therefore interchangeable" That should solve the problem.

Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 7:17 pm
by 1970man
smithskids wrote:In section H.1 Removing and replacing the brake-drum and hub. it states"remove the split pin from the axle nut and unscrew the nut with a set spanner, REMBERING that the axle half-shafts are threaded right-handed on both sides of the car and are therefore interchangeable" That should solve the problem.

That's very interesting, mine says:
"... remove the split pin from the axle nut and unscrew nut with a set spanner, remembering that the axle half-shafts are threaded
left-handed on the left-hand side and right-handed on the right-hand side of the car."
I'm even more confused now
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 8:20 pm
by mike.perry
Mine says the same as smithskids
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 8:29 pm
by smithskids
I have 2 workshop manuals and they both read the same. they are AKD530 and AKD530C. I checked my spare axle and the nuts are RH thread on both sides. I can't find a date on the manuals but AKD530C says issue 3. In AKD530 it says to reorder quote AKD530A. Looks as though you may have a misprint.Hope this helps sort you dilemma.

Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 9:20 pm
by mike.perry
Shaft axle drive 2 off, drum brake 2 off, nut 2 off
Changed LHD 126725, RHD 131858, from BSF to UNF
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 10:30 pm
by 1970man
mike.perry wrote:Shaft axle drive 2 off, drum brake 2 off, nut 2 off
Changed LHD 126725, RHD 131858, from BSF to UNF
My chassis # is 140252
So are we concluding that after the change to UNF, the n/s/r nut changed to being lefthand rather than righthand thread? That'll make finding a replacement even more fun.
I can't see a code reference for my manual, other than it being for "Home" cars.
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Wed Feb 24, 2016 10:35 pm
by 1970man
I suppose if I could find a replacement half-shaft, with nut, it might be a speedier solution to my search than looking for a nut on its own!!!! Are replacement shafts likely to be as tricky to find?
RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Thu Feb 25, 2016 4:10 am
by mike.perry
1970man wrote:mike.perry wrote:Shaft axle drive 2 off, drum brake 2 off, nut 2 off
Changed LHD 126725, RHD 131858, from BSF to UNF
My chassis # is 140252
So are we concluding that after the change to UNF, the n/s/r nut changed to being lefthand rather than righthand thread? That'll make finding a replacement even more fun.
I can't see a code reference for my manual, other than it being for "Home" cars.
RJ
No, we are saying that if your car is before the change it shoud be BSF, if after it should be UNF thread, unless the parts have been changed. The nut is ALWAYS clockwise thread
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Thu Feb 25, 2016 8:49 am
by 1970man
Very interesting, thanks to everyone who's been able to shed light on this anomaly with the manuals.
So one nut, or a shaft with nut included, are on my shopping list now. I've tried most of the usual outlets, but no joy as yet.
rgds, RJ
Re: Castellated rear hub/drum nut on a '51/'52 MM
Posted: Thu Feb 25, 2016 6:56 pm
by lowlight_HHO388
Plenty of BSF and UNF nuts for sale on Ebay. Just rebuilt the brakes on my 1949 Lowlight and both side are clockwise thread.