Need new crank pulley to auxilary hydraulics coupling

[smallfarmer]

Hi there, I have a M4000 that recently lost hydraulic power to the bucket. I learned a lot about this part of the tractor taking off the bonnet and learning that the 6 splined 3/4" shaft between the crank pulley and pump had broken at a weld. It looks like the splines were all worn out so they welded it back on. I brought everything to a local tractor mechanic and he cut the broken bit off of the 3 bolt flange and rewelded the shaft back onto it. That worked just fine, except it is not welded true, so there is a lot of wobble and I'm sure it will break again at the weld.
My question to you is where do I find this 3 bolt flange adapter? I've searched most of the obvious places online and there is nothing very similar. I've noticed a crank to pump adapter for Ford and David Brown but nothing with three bolts for my tractors crank pulley.

Thanks for any info in advance.

 

[kubotasam]

What kind of front end loader is it? If it is a Kubota loader you should be able to get the flange & shaft from a dealer.

 

[turck]

Hi there, I have a M4000 that recently lost hydraulic power to the bucket. I learned a lot about this part of the tractor taking off the bonnet and learning that the 6 splined 3/4" shaft between the crank pulley and pump had broken at a weld. It looks like the splines were all worn out so they welded it back on. I brought everything to a local tractor mechanic and he cut the broken bit off of the 3 bolt flange and rewelded the shaft back onto it. That worked just fine, except it is not welded true, so there is a lot of wobble and I'm sure it will break again at the weld.
My question to you is where do I find this 3 bolt flange adapter? I've searched most of the obvious places online and there is nothing very similar. I've noticed a crank to pump adapter for Ford and David Brown but nothing with three bolts for my tractors crank pulley.

Thanks for any info in advance.

Try your Kubota dealer, on my old deere its a two piece shaft with a coupling with rubber bushings that takes up the vibration. If you can't find a new one maybe if you took it to a professional welder he could do a better job, when you weld a continuous bead it tends to pull and that’s probably why it is out of balance.

 

[North Idaho Wolfman]

Post a picture or two and give some dimensions of the flange.
I have several just laying around here.

 

[smallfarmer]

Hey thanks, I am going to check out a Kubota nest time I am around one. I didn't think they would carry a part on a tractor so old, but maybe they could help...NIW I will post a pic soon as I figure that out

 

[smallfarmer]

 

[smallfarmer]

 

[smallfarmer]

It was 4 6/32" diameter flange, 1/2" holes, 2 3/4" oc between holes
the shaft was 6 tooth, 3/4" diameter, about 10" long

 

[North Idaho Wolfman]

I don't have one that matches that style.

But looking at the pictures and dimensions given I'm 99% sure I could fix it for you if you cant find a replacement.

 

[smallfarmer]

I went ahead and brought over the part to the local tractor guy, who doesn't really work on Kubota. He shrugged and cut off the broken parts and welded it up about 2 inches shorter for $10.

Went home and it fit! Put everything back to gether and it seems to be working for now - everything is a bit noisier, but nothing that sounds really bad. Hey its 35 years old...

 

[lsmurphy]

I went ahead and brought over the part to the local tractor guy, who doesn't really work on Kubota. He shrugged and cut off the broken parts and welded it up about 2 inches shorter for $10.

Went home and it fit! Put everything back to gether and it seems to be working for now - everything is a bit noisier, but nothing that sounds really bad. Hey its 35 years old...

There is a correct way to fix that.......and that ain't it.


Now! Learn how to manage your HUGE freak'n pics! Jeeeeesh!

 

[lsmurphy]

The correct way to fix that........

Chuck the flange in a lathe, turn down the stub to 1", mill stub for key, install Lovejoy.

Chuck shaft, clean cut the end and true to 3/4", mill for key, install Lovejoy.

You may also have had to reduce the hub or shaft length to accommodate the Lovejoy.

Use a locking collar at the splined end of the shaft to insure that the Lovejoy does not separate, you can also use tie wire at the Lovejoy as a safety.



As it stands, your complaint about it being 'noisy' is that the shaft is NOT true and it's also not balanced. Eventually you will destroy your pump and will cause damage to the crank and seals and possibly the bearings.