B7610 blowing snow ... and then it wasn't

[jcork]

I have a 2004 B7610 HST with ag tires and chains, and I am trying to blow snow with a B2660 60" front-mount blower. I was doing pretty well until I found that I had lost the drive to the blower (the entire mid PTO driveshaft assembly was laying on the ground). The rear section looks like it is complete and undamaged, and the front seems like it has sheared off the bolt that attaches it to the blower.

I own the Parts and Service Manuals, but I found neither was very helpful at showing me how to re-assemble the shafts. I'm not really certain what retains the driveshaft when the snowblower isn't mounted except for a sleeve with a flange and 2 bolt holes, that I suppose could keep the shafts from dragging on the ground (but didn't exactly look very robust to me).

Is that all there is to it? Is the mid PTO shaft only secured under the tractor with a couple of bolts and a sliding plastic sheath ?

I'd appreciate any guidance folks could offer on this.

 

[motorhead]

My understanding is that the bolt is a shear bolt and designed to fail instead of busting up the tractor transmission/PTO and or the snow blower. You might have jammed something in the snow blower causing it to seize. That bolt saved you.

 

[hodge]

The driveshaft should disconnect from the stub shaft on the mid pto- it doesn't stay under the tractor, unless it is being used.

 

[jcork]

The driveshaft should disconnect from the stub shaft on the mid pto- it doesn't stay under the tractor, unless it is being used.

I know the first foot of driveshaft stays with the blower (unless it breaks the shear bolt).

But the rest of the mid-pto shaft assembly normally stays under the tractor chassis? That's how it was when I bought mine, but I don't know what 'normal' is, I bought all mine used and I don't have anything else that uses that shaft.

 

[meanjean]

Did you figure it out?
As someone above mentioned it sounds to be a shear bolt.
One end connects to the blower, the other end goes to the PTO from the tractor. The "collar" from each end should look similar.

 

[jcork]

All worked out.

Apparently, the mounting for the mid-PTO came loose, and allowed the driveline (3-4 U-joints) to twist, and one of the u-joints wasn't locked tightly so it came off and the whole assembly came crashing to the ground as the telescoping length components slid apart.

Several zerks, to grease, several telecoping assemblies to clean and grease, and several locking collars to clean and grease, and a pair of 1/2" bolts to tie the front of the assembly to the bottom of the tractor frame at the front of the mid-PTO.

The snow blower itself has been educational. It has (3) shear pins of (2) sizes. The main pickup-screws that capture the snow each have a shear pin, and the impeller that throws the captured snow out the top has a smaller shear pin. The system will tolerate a little bit of gravel, but when it gets angry you start replacing shear pins.

I tried using a shear pin as supplied by the local ag supply house; mistake. They have me a #2-rated stainless steel bolt that 'smeared' but didn't 'shear'. I was lucky enough to replace that before it costs me some expensive parts. Messicks.com knows exactly which shear pins are needed.