Removing the Mainshaft nut - clutch

[Oggers]

Gents

The large Mainshaft nut - clutch end,  on my Ariel VB is absolutely stuck solid. I have the "special tool" which fits over the clutch centre, but that just bends when I apply torque to the the nut. I have to say it is plenty of torque too - courtesy of a long handled torque wrench. I don't really want to go at it even harder as I fear I may damage something... 

Advice welcome - heat from a blowtorch perhaps?

Many thanks   

[R]

Its not a left hand thread is it - not knowing these personally.

Advice welcome - heat from a blowtorch perhaps?

Well worth a try.
Don't cook anything in the vicinity though.
Red heat can alter heat treatment strength.
The nut you might need to think of as a disposable item.

And what are you doing using a torque wrench in reverse !
Not entirely recommended. !
I'd have to say a sudden whack from a whackometer (hammer) can sometimes shock things into releasing.
You wouldn't want to be doing this through a torque wrench though.
A single good hit across a good long handle is what is required, not a series of half hearted destruction/vengeance hits ..

Have fun.

[john.k]

Thread is approx 5/8x 20tpi RH........sounds like it may be Loctited.......suggest you heat the nut to oil smoking heat ..certainly NOT red hot,and try it with a rattle gun.........there should be sheetmetal locking tab...if thats not there ,then IMHO Loctite......apply moderate heat,and the smell of Loctite is unmistakable...........I once sloshed a king pin with loctite,and at the Transport Dept inspection pits,the Scottie inspector says ....".Och Aye...I  ken the reek O  Loctite.......the wee shaker will find ye oot".........he gave it heaps ,nearly ripped off the front wheel.......nothing came loose......I had swapped the axle side to side ,and he was testing the good side.........the Loctite side wasnt tested.

[Oggers]

Pretty sure I've had it off previously. Can't remember using Loctite, though that's not so say I did not use it....I have no rattle gun, nor impact driver. It's not only the nut, but also preventing the shaft from moving whilst applying Herculean torque to the nut. I'll get my blowtorch out.....

[john.k]

Thats the beauty of the rattle gun......no need to hold the shaft at all .

[R]

Isn't the idea that you keep the primary and drive chains fitted,
and put yer foot on the brake pedal while undoing the clutch nut ?

[john.k]

If you are holding things,you need to put the box in 4th ,and use a chain wrench on the rear drive sprocket on the gearbox....a proper chain wrench is easily made ...or you can get store bought ones  from tool suppliers.

[iansoady]

Of course the primary chain doesn't do a lot when you're dealing with the clutch mainshaft nut.......

[Oggers]

Quite so Ian......I did indeed stick a foot on the brake pedal whilst trying in vain to loosen the nut. The clutch slipped.....The arm of the tool - basically a friction plate with an arm welded on - just bends at the weld. Heat I think....

[R]

Of course the primary chain doesn't do a lot when you're dealing with the clutch mainshaft nut.......

The engine compression adds to the resistance.
But only if you've put a drive and driven plated bolted together into the clutch innards...