Wheel Nuts

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woo
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Wheel Nuts

Post by woo »

Perhaps I’m the only one who didn’t know this but……

Tired of rounding off the corners of new wheel nuts I decided to look into why they were a loose fit in a 3/8 inch BSW socket.

By measuring the distance across the flats of an old and new wheel nut and comparing it with thread form documents I found out the following:

The wheel studs on the Moggie are 3/8 inch UNF. Presumably Morris used UNF because it is a finer thread that BSW and therefore safer for wheel nuts. But, Morris have increased the width of the 3/8 UNF nut by .0225 inch to a total width of .710 inches to enable it to fit a 3/8 BSW socket. Thereby producing a non standard nut. Presumably they did this because this size was already in use on the car.

However, the new 3/8 UNF wheel nuts I have bought from several trade stands use the proper nut width of .6875 inches, which fits loosely into a 3/8 BSW socket and thereby spins when undoing a nut that has been tightened, perhaps over generously. The proper socket for a new wheel nut is 11/16 AF

So at present I need to use two sockets (3/8 BSW and 11/16 AF) to undo my wheel nuts. I guess the solution is to either use all new nuts, or try to get some old wheel nuts. I prefer the idea of using old nuts, to reduce the number of sockets I need to carry, but so far I have drawn a blank on where to get them. Does anybody have any idea if they are still available?

Ta!
Kevin
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Post by Kevin »

This is the 1st time I have been made aware of the size issue (just been lucky I guess) so I wonder if many owners are aware of the problem, I would thinf either ESM or Bull Motif would be the ones to speak to as they are pretty clued up on differences between old and new parts.
Cheers

Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)

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greydrinker
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Post by greydrinker »

bought 16 the other day of e bay only to find i have marina wheels
and hubs fitted and they fitted so you could look for marina or moggi
nuts on ebay
doobry
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Post by doobry »

I thought the Marina ones needed a different socket to the moggy? Hopefully you won't end up with 3 sizes :lol:
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