1800: 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/showt...=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-...QAAOSw48ZeQ8rd

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_Not...tal_portobello

Good Hunting!

[fishyboy]

Thanks Ron

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