Snowblower Kubota b2782b - bolts sheared

[Dave_eng]

The bolts that pass through the retainer and attach to the large drive gear have sheared. You can see the raw, broken end of one of the bolts in the drive gear.

I've been told that the two threaded holes in the retainer are for passing a couple bolts through to push the retainer away from the gear and slide it off the end of the shaft. Makes sense, but I don't want to do that until I have two new replacement bolts for the ones that got sheared off.

I'm not sure what to do about the square shaped key that sits in the groove of the shaft... does that have to come out first, and if so, how is it removed?

I suggest you consider someone has repair the blower using non standard parts.

Looking at Messicks parts diagram for several versions of your blower, all I see is a $43 sprocket with two Allen screws securing it to the keyway and shaft not an industrial tapered bushing style sprocket.

Dave

 

[eserv]

Some Kubota shear bolts have grooves cut in them to weaken them.

You need to be very careful with what you use or a broken gear box is possible.

Dave

The grooves are there so the bolt shears without smearing also, making them much easier to remove and minimizing damage to the shaft and collar they go through. You also have to remember the reduced diameter when tightening them to! They need much less torque than full diameter bolts

 

[jmatz]

The friction-fit of this assembly that I was relying on for this winter finally failed. Which is a good thing. I couldn't get the retaining collar to budge when I tried to get it off using two bolts in the threaded holes intended for this use.

But it gradually loosened, and I was able to remove the assembly. It helped a lot to gently heat the retaining collar with a plumbers torch, expanding it enough to allow the bolts to do their job. The bolts in the photo are not the best ones to use (stainless, weak), but their only purpose was to push the collar off the shaft.

Now have the proper grade 8 bolts to re-attach the assembly and get back to clearing snow. There is some wear on the collar surface that mates with the sprocket, but it will be fine for the rest of the winter. In the spring I'll replace that part.