Snowblower shaft looks keyed in place

[babzog]

So I was out changing the oil in my snowblower's gearbox yesterday and I noticed that, where the pto shaft connects to the gearbox shaft, it's not only held in place with the shear pin/bolt, but it's also held in place with a big square key (see red arrow in pic). Wondering if I should remove that and just have the shear bolt holding the two in place?

 

[GPintheMitten]

Mine also has a keyway. But previous owner drilled a hole for the shear bolt right thru the keyway.

I think you'll be fine with just the shear bolt. Mine is.

 

[babzog]

That's what I was thinking. Plus, if that key is locking the two shafts together and something jams in the blower, am I not risking damage to the tractor? Seems the shear bolt has been rendered rather useless here.

 

[PILOON]

If there is a keyway, then that is not meant to be a sheer bolt location.
The bolt located near the keyway is meant to prevent creeping of the U-joint fitting.
On some they merely lock the key with a large (like 3/8") set screw but creeping can still happen and you could actually drop your shaft half.
That is why a bolt is often installed on some blowers, key takes the torque and bolt prevents slippage.

Look elsewhere for the sheer bolt. Often on the impeller hub and generally you will find one on each side of the auger.
Models with chain and sprocket system will usually have the sheer bolt located at the drive sprocket.

 

[fluggies4]

That's not a shear bolt. It's only meant to keep the yoke from sliding off of the keyed shaft. The shear bolt yoke assembly is on the tractor end...unless a previous owner has changed the yoke(s).

 

[babzog]

I looked at the end of the pto shaft that connects to the tractor and saw nothing that looked like a shear bolt. On the end that connects to the gearbox shaft, there appear to be two plates (inside the bell shaped guard) with a bolt through them on one side. Would that be the shear bolt?

 

[GPintheMitten]

I looked at the end of the pto shaft that connects to the tractor and saw nothing that looked like a shear bolt. On the end that connects to the gearbox shaft, there appear to be two plates (inside the bell shaped guard) with a bolt through them on one side. Would that be the shear bolt?

Yes. I believe so.

 

[fluggies4]

Yes, that would be it.

 

[babzog]

That's great to know, thank you! Now, I need to trade in the bolts I picked up for some shorter ones. LOL

 

[mjym]

take it apart and put grease in the key and around the shaft and it wont rust and put back the key and the bolt and you will noy have probleme to take it apart