Oh Bugger bugger bugger!

[andymadmak]

Back from hols today

Took Beastie out for pre le mans shake down spin.
Strange noises from n/s rear hub. thought it might be sticky brake, 20 miles later handling goes a bit squirrily!
Investigation reveals the big centre nut on the drive shaft (the one in the middle when you take the centre wheel cap off)has unscrewed itself! Almost competely off!
This has never happened to me before.
Why has it done this? will I have knackered the rear wheel bearing (new last year) or can I just tighten it up again? The nut is hard to turn, even in its current slackened off state - does that mean the driveshaft thread is ferked? Can it be fixed by wednesday?

Really don't fancy taking a Volvo to le mans!

Andy 400se

[jvaughan]

isnt that the same nut they have to use a 6foot saffolding pole on a socket wrench to tighten to some silly torque ?

[dexy]

it should go back on take wheel off have a look at thread and make sure its not damaged the nut should be tight cause it should be one of those nylon tread nuts
get some lock nut stuff put that on then tighten nut back on with socket n scaffy bar ,let nut lock set then take her out for a 50 mile spin ,check again to make sure its still tight . ive just replaced my bearing tightend it up as much as i can ,with bar, lock nut stuff,checked it bout 150 miles later and it came loose and tightend it back up,just keep checking it on a regular basis otherwise your wheel will pass you one day .some people drill nut and drive shaft and split pin them ,but i think it would weaken the drive shaft.
ps dnt forget to check the other side as well and if your of to le mans put ya socket n bar in the boot .
cheers neil

>> Edited by dexy on Sunday 6th June 09:02

[brm brm]

That old carrot again - you are not the first! First things first buy a new nut! Torque correctly (230ft/lb) according to the bible (I bought a dedicated 3/4" socket for the job plus a wrench from work). Lots of opinions about drilling the hub - I dont like it as you can end up with a different hole every time you fit the nut, my hubs had 2 holes in already; however, since I've used Loctite threadlock I've had no problems. Also suggest putting a dab of tipex or similar across the nut and hub - you can then see easily whether the nut has moved. Its still worth checking occasionally.
Hope this helps.

[ssc1]

of course if you were close to me i would be able to lend you my very large torque wrench and i would use a spit pin every time and just try to line the holes up even if it meant shimming as i dont rate thread lock on something as important as this and TVR's do tend to vibrate alot at the back end when going for it..

[andymadmak]

Thanks for the offer Ian, I'm all sorted now.
Had to buy a new bearing as the seal was wrecked. All back together now, tested and feels fine. Couldn't use split pin as the nut is so large it covers all the available thread (these are new nuts fitted last year at RT)
Used some thread lock and put about 300lbs on the nut! If it undoes itself again I'll buy a smaller nut and pin it.
All in all a lucky escape! Thanks to all who contacted me, and a special thanks to Mike who drove all the way from Nottingham to lend me his torque wrench and mechanical guidance.
Le mans is back on!

Andy

[AM400]

dexy said:

some people drill nut and drive shaft and split pin them ,but i think it would weaken the drive shaft. >> Edited by dexy on Sunday 6th June 09:02

Both my nuts are pinned (ooh err) never had any problems.

Andy

[andy390]

AM400 said:

dexy said: some people drill nut and drive shaft and split pin them ,but i think it would weaken the drive shaft. >> Edited by dexy on Sunday 6th June 09:02 Both my nuts are pinned (ooh err) never had any problems. Andy

I have to agree with Andy here. shortly after getting my 390,i had to replace my NS rear wheel bearing and seals. After threadlocking and torquing until the veins in my head were throbbing, i thought i should be OK,but after one week,i re checked the nut and it had undone two full turns! for me the mechanical method(split pin) is the only surefire way of fixing the nut,besides when i put the old nut back on,the existing holes lined up anyway. PS Northern tool is a good place to get a reasonably priced 34 socket set and Torque wrench from... HTH
Andy

[sevans]

ssc1 said:

of course if you were close to me i would be able to lend you my very large torque wrench and i would use a spit pin every time and just try to line the holes up even if it meant shimming as i dont rate thread lock on something as important as this and TVR's do tend to vibrate alot at the back end when going for it..

Have to agree. The first time I did this I drilled the nut first, fitted it and then drilled the shaft. The second time I fitted a new nut, marked it and drilled it so that the holes would line up with the original hole drilled in the shaft. I don't think drilling more that one hole through the shaft is a good idea. I have only done this on the N/s wheel as this is the one that is trying to undo the nut. The other side is just locked with threadlock.

[dickymint]

Maybe wire-locking is a better option?