Damaged threads on rear drive shalf - help please!

[fishyboy]

Hi all,
This week I decided to overhaul the rear brakes on my 1968 1800S. Anticipating this job a while back I bought one of the hydraulic pullers disused on the forum (https://www.volvoforums.org.uk/showthread.php?t=264459&page=2). However, I didn't screw the hub nut back on (switched around the other) on far enough and managed to split the hub nut in two while tightening the puller up (the hubs/drums hadn't been of in my 5 year ownership).

Having got the hub off and rebuilt the brakes I tried to wind on the new nut but it would go on about one turn by hand. Got my 1 1/4" socket out applied some gentle force and moved it about a 1/4 turn and got no further. Tried the other new nut with the same results. Tried the unbroken original nut from the other hub same result. Checked with the supplier they sent they sent the correct nuts. Broke down in "tears" and vowed never to do any work on my cars ever again. Clearly I have damaged the end threads on the drive shaft, (even though I can't see any obvious damage).

Can anyone help?
I would like to repair the threads rather than have to replace the drive shaft. Does anyone know the pitch/TPI etc that might allow me to but an appropriate thread file. Any other suggestions much appreciated.

Phil

[Bob Meadows]

As recognised the thread size needs to be determined - once done then you can move onto the next stage with a thread file or die: ~ if the size isn’t forthcoming via the forum then engineering suppliers or nuts/bolts supplies are generally cooperative in identifying threads sizes (from the new nuts etc.) or the company that sold the same may help.
You can then beg / borrow- purchase the tool you need to clean up the threads- stretched?
Good Luck
Bob.

(I have Imperial sizes but probably not the range used for your car ?)

[fishyboy]

Thanks Bob
I found a Whitworth 55 degree thread pitch gauge in my tool box and got a match to the "14G 7/16" blade. I assume that is 14 TPI but what in the 7/16 bit mean?
Brookhouse told me the bolt was a 7/8" UNF so I was wondering if this might be the right tool.

https://www.ebay.co.uk/itm/NEW-Snap-on-7-8-14-UNF-rethreading-spindle-thread-cleaning-repair-die-inc-VAT/333512582297?hash=item4da6e62499:g:6CQAAOSw48ZeQ8r d

Phil

[Bob Meadows]

I do have UNF but after checking not that size-so that's out.

The die nut should work once you have the size and useful in confined spaces :~ You don't have a left hand thread here do you?

(not on a Volvo but I have a car with them-- don't ask how I know!)

Good Luck
Bob

[mocambique-amazone]

Here you are

https://youtu.be/dYu_fl59Ztw

Enjoy

Good luck, and patience. Kay

[fishyboy]

Many thanks Bob and Kay,
Ordered thread file and die nut and hopefully one of these will sort the problem.
Phil

[Ron Kwas]

Phil;

The trick is to inform yourself before doing the job and getting it wrong...

See: https://www.sw-em.com/Brake_Drum_Notes.htm#metal_portobello

Good Hunting!

[fishyboy]

Thanks Ron
:sarcastic:
Phil

[blueosprey90]

Not sure how much room you have but …

when all else fails, you can cut a good nut in half, clamp it on the stud past the damaged area with a good set of vise grips and then turn it back out to de-knacker the threads on the stud from the opposite direction.

You can also try doing this with just one piece cut out of the side of the nut as it may be a bit easier to work with.

[fishyboy]

Thanks Blueosprey,
That might just work as I cracked the original nut in two in the first place. It will avoid trying to start on the damaged outer threads.
Phil

[tdz840]

If all else fails Brookhouse supplies drive shafts now👍

[ksmi]

Not sure how much room you have but …

when all else fails, you can cut a good nut in half, clamp it on the stud past the damaged area with a good set of vise grips and then turn it back out to de-knacker the threads on the stud from the opposite direction.

You can also try doing this with just one piece cut out of the side of the nut as it may be a bit easier to work with.

Morning Blue,Nice to know the 'Bush Mechanics' are still alive and kicking,there is always more than one way to skin a cat.

Best regards.

Keith.

[CLIVERALLY]

Try Rob Whitton or Dai... they will no doubt be able to help with a shaft and just re[lace it.

And dont be hard on yourself. I have worked on cars for 40 + years including running my own business (working in modern junk sadly). Anyone who states they have never made a mistake when repairing vehicles is either a liar or oblivious they have done it.

I personally would ony re thread if you are 100% the nut will be secure and not loose and gripping. If any of this is not in place or you are unsure then buy new or used along with a new oil seal. and check and or replace the wheel bearing whilst you are at it. The process is shown brilliantly on You Tube Amazon Cars - wheel bearing replacement.

[Ron Kwas]

Phil;

The tool you need, and I recommend is shown at the link I gave...

[fishyboy]

Hi all,
Many thanks to everyone who helped me out. I used the two half's of the original broken castle nut to run the threads out from in to out (thanks Blueosprey). That then allowed me to run the die nut I bought from out to in and that cleaned up the threads a second time. With a bit of lube and working the new castle nuts backwards and forwards i managed to get both on. Brakes bleed and ready to go.

The only problem now is I noticed one of the wheel nuts ran straight through the hole in the steel wheel. I can only guess that might have happened when a over zealous tyre fitter got carried away with his air-gun when he put the wheel back on after fitting some new tyres last year. I guess it means I'll have to but a new wheel!

Thanks
Phil

[Derek UK]

Wear to the wheel holes is common after all these years but rarely gets checked until too late, as you have found. The first sign is that the hole gets sharp edges, be careful when you check. This will only get worse but a smear of grease will at least allow the nut to slide on the surface rather than wear it even more. I've made the comment before that many who check WILL find they have wear and damage. Don't take good wheels to the scrapyard!

[fishyboy]

Thanks Derek
I assume in my case that once the wheel nut passes through the widened hole its time to get a new wheel?
Phil

[Derek UK]

Thanks Derek
I assume in my case that once the wheel nut passes through the widened hole its time to get a new wheel?
Phil

Absolutely. Check them all. You do have a spare wheel?