Special tool 600300

I don't suppose anybody in the Portsmouth / Hampshire area has a main shaft nut tool ST 600300 that they would hire out for a couple of days ???
Just acquired an overdrive and I don't really want to start beating the nut off with a hammer and punch, just yet !
I have got drawings for the correct tool but it is just a bit too big for my old lathe to handle safely.
If not I will have to bite the bullet and buy one.

I fitted my overdrive last month and it all just came apart beautifully - one very gentle tap with a screw driver and the nut was loose... getting the O/D into the G/B housing was a bit of a pain, but, only for 10 minutes or so, only advise - if all the studs came out rather than the nuts coming off them, the bottom two studs need to be in before fitting the O/D - they won't fit on after the O/D is in place.

i welded a big socket into each end of a piece of scaffold pole then cut the teeth/castles with a 1mm cutting disc on my angle grinder, it's a bit clumsy in use (i have small hands) but does the job nicely

Hi. Don't buy one, bump is right. Absolutely no special tool other than flat screwdriver and hammer needed. I fitted my overdrive the other month and that is all I did it with. The nut on the end of the shaft is so robust anyway, that I would doubt that you could damage it much.

Remove cover plate and smack downwards on one of the lugs with a blunt chisel, remember to pry up the locking tab washer though

Remember to knock up the locking washer tab though otherwise you'll be trying to undo it forever No need to buy a tool as said, just used a punch and a hammer to do mine and it did thee job just fine

Could you post the drawing? My lathe and mill are up to this, I could make three or four and send them north/south/east/west so folks can use them.May take a while to run them in but not looking for money. I was thinking of getting a main shaft nut and making one to suit.

divie said:

Could you post the drawing? My lathe and mill are up to this, I could make three or four and send them north/south/east/west so folks can use them.May take a while to run them in but not looking for money. I was thinking of getting a main shaft nut and making one to suit.

Click to expand...

No problem, I will try and post it on today.

OK you have all convinced me, we will go with the big hammer ! This time.

All you need is a socket to fit the castled nut, if you've got a series gearbox somewhere I'd take it off and measure up properly to make sure you dimensions are spot on.

Having said that though there is no need for a special tool as a drift or blunt chisel will do but if you fancy making one then I may actually have a spare nut somewhere

That should be the drawing attached ??? It was available on open access so I hope I don't **** off the guy that originally posted it.

Dr_evil said:

All you need is a socket to fit the castled nut, if you've got a series gearbox somewhere I'd take it off and measure up properly to make sure you dimensions are spot on.

Having said that though there is no need for a special tool as a drift or blunt chisel will do but if you fancy making one then I may actually have a spare nut somewhere

Click to expand...

it'll need to be a pretty deep socket as the shaft support bearing surface sticks out quite far

when i made mine (standard depth socket) i had to bore the the square drive out of it

which is why i welded it into a short piece of scaffold pole and then welded another one in the other end

remember that nut is supposed to be torqued up to 80-85 ft lbs

i did have one slacken off on me prior to building the tool which then allowed the shaft to float and locked the gearbox up which immobilised me

i had to pull a halfshaft out to get it back out of gear and tow it home

for the effort involved in making a tool, if you have the facilities get on with it, it's a whole hour out of your life making it in the crude way that i did

this thread iis starting to worry me - i took off the top plate and the back cover where the O/D goes - there is a nut holding the redundant gear thingy on - you tap it with a screw driver and it comes straight off... nothing more... didn't have castle nuts, lock tabs to bend or anything - just a dead simple nut...

PJ.768 thanks for the drawing. I will make them up and post on here when they are available.

May take a month or two in between jobs. I will have to scrounge the use of a mates spark machine to put the 1/2" square drive in. All doable though.

You should have a castle nut bump whoever did yours last time must not ahve had any and thought this'll do….

divie said:

PJ.768 thanks for the drawing. I will make them up and post on here when they are available.

May take a month or two in between jobs. I will have to scrounge the use of a mates spark machine to put the 1/2" square drive in. All doable though.

Click to expand...

No Problem, It might be simpler to leave a square or hex on the end instead of messing around broaching a square hole?

Ok I will leave a hexagon on to suitable size. Easy for torque wrench then, must have had brain fade not thinking about it and looking at the drawing. should have some EN24T in the workshop.

Bump said:

this thread iis starting to worry me - i took off the top plate and the back cover where the O/D goes - there is a nut holding the redundant gear thingy on - you tap it with a screw driver and it comes straight off... nothing more... didn't have castle nuts, lock tabs to bend or anything - just a dead simple nut...

Click to expand...

Sounds like that could become expensive !

Bump said:

this thread iis starting to worry me - i took off the top plate and the back cover where the O/D goes - there is a nut holding the redundant gear thingy on - you tap it with a screw driver and it comes straight off... nothing more... didn't have castle nuts, lock tabs to bend or anything - just a dead simple nut...

Click to expand...

That castle nut takes up all the float on all the gears on the mainshaft (James Martin may jump in and strike me down here if I'm wrong) so I'm surprised it held in any gear under load! The problem with using the chisel is that you can't measure the torque when you tighten it back up. I used an air chisel to get mine off as it was f-ing tight. So I put it back on f-ing tight! The nuts are only a couple of quid so put a new one on with the O/D. The lock tabs are only 70p each so the P/O of your g.box was a right tight ####!

loose nut would only alter preload on 1st gear ,but the whole shaft moving isnt going to do much good 3rd and input , 2nd and 3rd preload is governed by length on braas bushes and selectable washers either side

jamesmartin said:

loose nut would only alter preload on 1st gear ,but the whole shaft moving isnt going to do much good 3rd and input , 2nd and 3rd preload is governed by length on braas bushes and selectable washers either side

Click to expand...

See, told you