Wrong wrench, or wrong nut?

A

armadefuego

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Dec 19, 2024
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So i have this nut. It was the rear bottom (#2) on the head:
https://photos.google.com/photo/AF1QipMvZ4UPfNlOpQE9Fj7F4E2leBskGk9kD1SfXWFn
and the wrench (funny "S" shaped 1/4W).
It seems 1/4W is too small for the nut. But a 5/16W is fine ( or the pictured 15mm).

Before i grind down _another_ wrench....
Is that nut supposed to be 5/16W, or 1/4W?
The nuts on the 2 top front studs seem to have the same thread and fit a 1/4W just fine.
 
The wrong wrench fits every nut and bolt on my Seeley 850, but I also have hands where my feet should be. To work on, it is a nightmare.
 
L.A.B. said:
Yes, that works.

Here's the nut.
andover-norton.co.uk

Andover Norton - CYLINDER BASE/ HEAD NUT 3/8

CYLINDER BASE/ HEAD NUT 3/8
andover-norton.co.uk

And the spanner that AN sells to fit it = 1/4"W.
andover-norton.co.uk

Andover Norton - COMBINATION SPANNER 1/4

COMBINATION SPANNER 1/4
andover-norton.co.uk
Click to expand...
Thanks.
I suspected that the nut that i took off was the _wrong nut_, even though it has been undisturbed for over 30 years.
I have another version of that wrench, King Dick.


I ground down 3 wrenches until i was able to get it off. The one that worked was an old 5/8 ground to .81 inches. Turned out that it was not even close to torque spec, so that worked.

Big fun!
 
triumph2 said:
Possibly some confusion as a 1/4W is the same size as a 5/16 BS
Click to expand...

Yes, the spanner sizes are the same (0.525") but it took a spanner ground to 0.81 to fit the nut so I don't follow?

The stud/nut thread of course is neither 1/4"W or 5/16".
 
The nut was not a 1/4 BSW, as originally fitted. It was 5/16W, with the same thread size. Not sure how that was sourced.

The wrench grinding was guesses as i was unable to fit anything to measure across the flats. And no idea about the space behind the nut.
So i just started grinding old wrenches that were larger than 1/4W until i got one to loosen the nut.
When i got the nut fully off it was apparent that the 5/8 SAE was, actually, too large.

The .081 was measured from a face of the nut to the cylinder. It is likely that the 5/8 worked because it was jammed between the nut and the cylinder wall.
So it didn't fit the nut, but got the job done.
 
For a long time working on my Norton I didn't have any WW spanners or sockets just used AF tools they were forced on but the last 25 years I have built up my WW tools, makes it a lot better using the right size tools and a few ground down tools for them hard to get motor nuts and bolts, my workshop now has every tools/pullies needed to work on my Norton as well any old British bikes without having to do a bog job using the wrong tools.
Had to mod a few jaws on the pullies that suppose to fit but didn't, but great now they all fit right and a hard job now becomes an easy job without spending time to modified tools to get something apart, should have done this 45 years ago instead of being a rough bastard.
 
ashman said:
For a long time working on my Norton I didn't have any WW spanners or sockets just used AF tools they were forced on but the last 25 years I have built up my WW tools, makes it a lot better using the right size tools and a few ground down tools for them hard to get motor nuts and bolts, my workshop now has every tools/pullies needed to work on my Norton as well any old British bikes without having to do a bog job using the wrong tools.
Had to mod a few jaws on the pullies that suppose to fit but didn't, but great now they all fit right and a hard job now becomes an easy job without spending time to modified tools to get something apart, should have done this 45 years ago instead of being a rough bastard.
Click to expand...
Much the same here. SAE and Metric tools get close, but they just aren't the same.
I just don't, yet, have enough BSW to risk grinding one down in the hopes it will fit.
and it didn't make sense, to me, to grind a wrench down for what was evidently the wrong nut.
That being said i use one of my 7/16th wrenches for the front bottom head nuts. It, unlike another 7/16 from the same manufacturer with the same model number, or my BSW wrenches, fits without any grinding.
 
armadefuego said:
That being said i use one of my 7/16th wrenches for the front bottom head nuts. It, unlike another 7/16 from the same manufacturer with the same model number, or my BSW wrenches, fits without any grinding.
Click to expand...


Yes the later sleeve nuts have a 7/16"AF hexagon (3/16"W also fits although not so well but is the spanner AN sells).

andover-norton.co.uk

Andover Norton - COMBINATION SPANNER 3/16

COMBINATION SPANNER 3/16
andover-norton.co.uk

The earlier sleeve nuts were 1/4"W.
www.rgmnorton.co.uk

CYLINDER HEAD SLEEVE NUT

USED ON ALL 750 ENGINES, 3/8" X 26TPI THREAD. FITS THE TWO FRONT STUDS LOCATED IN THE CYLINDER HEAD. 1/4" WHIT SPANNER SIZE. LSO SEE 063192S FOR THE LATER REDUCED HEX (3/16" WHIT) STAINLESS VERSION OF THIS FITTING.MATERIAL: PLATEDOVERALL LENGTH: 1.934"THREAD: 3/8" X 26
www.rgmnorton.co.uk
 

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