6640 Ford PTO drive shaft removal

[BillHillyBob]

I have a 6640 Ford tractor that the spines on PTO drive shaft are stripped. Have the tractor split in two and trying to figure out how to remove the drive shaft.

The manual doesn't talk about how to remove the shaft. Is there away to simply remove the shaft from the front or am I going to have break the tractor completely down and remove it from the rear of the tractor. Removing the rear cover, PTO clutch and everything else?

 

[BillHillyBob]

This is the shaft I need to replace.

 

[Pennine Ploughing]

big job changing it,
easiest way is get a 3/4 drive impact socket, machine the female boss end out to fit socket, weld in place,
get a thin cutting disc in 4 1/2" grinder, cut a square on end of the shaft to fit socket, making sure its in the middle of shaft,
and bolt it back up, will last for years

 

[BillHillyBob]

big job changing it,
easiest way is get a 3/4 drive impact socket, machine the female boss end out to fit socket, weld in place,
get a thin cutting disc in 4 1/2" grinder, cut a square on end of the shaft to fit socket, making sure its in the middle of shaft,
and bolt it back up, will last for years

Thanks for the short cut. When I use this tractor 90% of the time the PTO is being used. I will replace the drive. I will keep your method in mind should one of my utility tractors needs the drive replaced.

 

[Pennine Ploughing]

That's no problem, we did a 7810 a few years ago, and it's done a lot of pto work since, from spreading feet to mowing grass, and hedge cutting and never been any bother, the 2 bits you cut and alter are to replace anyway, so nothing to loss we thought

 

[bobk]

I'd find out off a mechanic , looks like gearbox and cab off job . @agrimax

 

[Mur Huwcun]

If it’s like the older ones and I can’t see why it won’t be then you need to split between the gearbox casing and rear axle to remove the circlip that holds the shaft in place

 

[rob h]

We did a 7610 year's ago and had to lift the cab off and unbolt the gearbox off the back end .then pull the shaft out backwards .Never done a 40 series so may be different

 

[Mur Huwcun]

You don’t have to take cab off just support the front from shed beam above but it’s a doddle with cab off if you have the time and gear to lift cab off.

 

[BillHillyBob]

From what I can see in my research I will have to split the transmission gear box from the rear drive housing to pull the PTO drive shaft from rear of the gearbox. It cannot be pulled from the front.

Dies anyone know how much the transmission weighs?

 

[agrimax]

The handiest way is to bolt the engine back on to the gearbox and wheel the lot out from below the cab. Then you can sling the gearbox from a loader or engine crane and remove it from the engine. Sort out the shaft and reattach the box to the engine and push the lot underneath again. You'll need the plate off behind the lower fuel tank (if there is a tank) to see that the gear on the back of the box meshes with the hydraulic pump. If you don't the gear will break in two!!!

 

[BillHillyBob]

The handiest way is to bolt the engine back on to the gearbox and wheel the lot out from below the cab. Then you can sling the gearbox from a loader or engine crane and remove it from the engine. Sort out the shaft and reattach the box to the engine and push the lot underneath again. You'll need the plate off behind the lower fuel tank (if there is a tank) to see that the gear on the back of the box meshes with the hydraulic pump. If you don't the gear will break in two!!!

Hey thank you very much for the break down and tip on how not to break the gear.

Funny times ahead.

 

[db9go]

If you have it split at the clutch at the moment then do all you have to in there like new hub and clutch then rejoin and then split at the back end and then you can change the shaft,
Have done it many times like that

 

[yellowbelly]

What he said ^^^

All I would say in addition is, before you assemble the clutch, offer the new hub up to the ipto shaft by hand just to make sure it will slide on when you push both halves of the tractor back together (sometimes the splines get a bit raggerdy)
If it doesn't go on easily file/grind the knackered ipto shaft so it does.
Just saves a bit of swearing when 'buckling it back up'.

 

[db9go]

What he said ^^^

All I would say in addition is, before you assemble the clutch, offer the new hub up to the ipto shaft by hand just to make sure it will slide on when you push both halves of the tractor back together (sometimes the splines get a bit raggerdy)
If it doesn't go on easily file/grind the knackered ipto shaft so it does.
Just saves a bit of swearing when 'buckling it back up'.

Good point i meant to say cut the old shaft end of but try the new hub on the new shaft first to make shore it fits

 

[yellowbelly]

Good point i meant to say cut the old shaft end of but try the new hub on the new shaft first to make shore it fits

Them old ipto shafts make a handy pry bar too if you flatten the little end

Waste not, want not

 

[BillHillyBob]

That's no problem, we did a 7810 a few years ago, and it's done a lot of pto work since, from spreading feet to mowing grass, and hedge cutting and never been any bother, the 2 bits you cut and alter are to replace anyway, so nothing to loss we thought

I think we are going to try your idea. We have a full blown machine shop, Lathe, mill and welders. Any other tips?

 

[Pennine Ploughing]

I think we are going to try your idea. We have a full blown machine shop, Lathe, mill and welders. Any other tips?

Buy or find a good impact socket, turn the splines out of the center boss that bolts on, to a good pressing fit, press in so square is where the splines where, and weld around
Now the shaft, where the splines are at the end, with a skinny plasma cutting disc cut a square on shaft to fit the boss with socket in,
Don't leave any extra on socket as it will foul if to big


You are only cutting and altering what is to replace anyway, nothing else,
And 1 we did has done many hours since and most on pto work

 

[Pennine Ploughing]

@BillHillyBob how did you get on with this

 

[bhancock51386]

I’ve had this problem 2 times in the past 2 years on a 7740. Had 2 different mechanics split tractor and remove transmission to replace the hub and shaft two different times. Tractor is back together now pto is working, but just doesn’t seem right to me. Makes a grinding noise as the pto engages. Did both mechanics miss something. I’m scared to have to tear into the tractor for a third time. The tractor had about 200 hours put on it between the first and second splits. Shaft and hub should last longer than 200 hours. If anyone has any thoughts they would defiantly be appreciated.