Did Ya Know? MF2360 snowblower has a "Fan Shear Plate"

[mgstevens]

In preparing for the season, I bought the new MF2360 and a set of shear bolts from the dealer. In the last 2 weeks we've gotten about 3 feet or more of snow to make up for a very slow, warm start to winter.

Earlier today, I lost the fan while finishing up clearing about 4" of light powder snow, but at some cold temps (for us..). I figured I'd snapped my first shear bolt and went to get the replacement, but I was wrong..

I'm not sure if the older 2360's have this, but my new unit has a thing called a "Fan Shear Plate" (pictured below..) and it has a shear bolt. The spec is 1/4-20 x 1-1/4" and the dealer tells me it just takes that size in a grade 5 bolt. I got a few in town for 60 cents.

What gets me is that there is no mention of this shear point in the user manual nor did the dealer bring it up when I ordered a "set of shear bolts.." so it may only be on the latest version.

Anyway, other than this blip, the unit is moving snow like a champ!

 

[irvingj]

Very interesting! Mine's a 2007 (on a 2310), and only has one snap-ring --for disassembly-- and the single shear bolt on the fan. Something new, I guess. What's the socket-head bolt there? (Are there two of those?)

 

[mgstevens]

What's the socket-head bolt there? (Are there two of those?)

If you are referring to the 5/16 lock nut forward of the "Fan Shear Plate" in the image, that is a bolt coupling the shaft to the tube that ties in the "fan shear plate." The OEM bolt in the "fan shear plate" is a hex-head, but the dealer replacement is a simple grade 5 bolt.

The dealer tells me the bolt is listed as 1-1/4" but that bolt from my local supplier has a non-threaded top end that would prevent it from shearing. Also, the OEM bolt is only 1" and is threaded through the whole shank. I'm pretty sure the manual does not cover this because it's new and the manual is not. However, the bolt spec from the dealer is not accurate either. The 1-1/4" sticks out at least an extra 1/4" at the back of the plate.

I will move to a 1" full-thread replacement to make sure if it needs to shear, it can. Also, why would this fan assembly need two shear points?

I think I'll call the snowblower manufacturer in Quebec and get the straight poop on this...

 

[mgstevens]

Yeah, I called RAD Tech in Quebec to find out the dealer sent me an old, outdated manual with the snowblower. Explains much of the confusion I have experienced since delivery of the unit.

The bolt through the shaft is meant for coupling only, and the only shear bolt on my unit is the 1/4-20 x 1-1/4" grade 5 bolt joining the two halves of the "fan shear plate."

The mfg is sending me both a PDF and print versions of the correct manual.

Sometimes you need to go direct to the source.

 

[Jaylegger]

This shear plate is listed in the Massey and Kubota manuals as an early model S/N blower. However my first (2009) 2360 blower had the through the shaft shear bolt. I purchased a new blower in 2016 (give or take a year) and this new blower has the shear plate. The plate seems to shear far less then the through the shaft method.

I switched to purchasing all shear bolts from my much closer Kubota dealer for the BX2750 blower as it's identical to the MF2360. Hears a link to the plate shear bolt in question. Both Massey and Kubota list the same grade 5 bolt with a .35" collar prior to tapering down to the threads.

Massey part# 4263511M91

Kubota part# 70060-01075

Massey Ferguson 4263511M91 SHEAR BOLT 1/4 2� X - Jacks Small Engines

Kubota: BOLT,SHEAR FAN, Part # 7��6�-�1�75

 

[mgstevens]

I got some slightly confusing info from the tech support person at the manufacturer RADtech.

The OEM shear bolt is threaded all the way up the shank while the replacement has a solid collar, which seems to go against the standard for shear bolts which are typically either threaded at the shear points or notched. She seemed sure the bolt needed a threaded shank all the way to the bolt head.

She then checked with their engineering people and was told that they use a full-shank threaded bolt at the factory for ease of assembly, but the replacement is indeed a collared bolt.

Guess that is why everybody (dealer, Jack's, etc..) is using them.. They just need to be a grade 5. Perhaps the OEM lighter threaded shank sheared on me with no apparent blockage (light powder snow)because it is a little lightweight for the job..

My local supplier seems to have what everybody else is using.

 

[MF RED in MT]

I got some slightly confusing info from the tech support person at the manufacturer RADtech.

The OEM shear bolt is threaded all the way up the shank while the replacement has a solid collar, which seems to go against the standard for shear bolts which are typically either threaded at the shear points or notched. She seemed sure the bolt needed a threaded shank all the way to the bolt head.

She then checked with their engineering people and was told that they use a full-shank threaded bolt at the factory for ease of assembly, but the replacement is indeed a collared bolt.

Guess that is why everybody (dealer, Jack's, etc..) is using them.. They just need to be a grade 5. Perhaps the OEM lighter threaded shank sheared on me with no apparent blockage (light powder snow)because it is a little lightweight for the job..

My local supplier seems to have what everybody else is using.

View attachment 637035

1/4" diameter "machine screw" are threaded all the way and come in varied style head types.

Is this what you are looking for:

KC

Socket Head Cap Screw, 1/4-2 x 1", Alloy Steel, Black Oxide, Hex Socket Coarse Thread, 1/4 inch Hexagonal Allen Bolt, Length: 1 inch, Full Thread (Quantity: 2): Amazon.com: Industrial & Scientific

 

[mgstevens]

That certainly looks like what they used at the factory, but everybody in the field is using a 1-1/4" grade 5 bolt that has a 3/8" long solid collar above the thread, as shown in the pic from my last post.

That is what I found at my local supplier, so for now that is what I'll go with. Perhaps the fully threaded shank is weaker/too weak..

 

[MF RED in MT]

That certainly looks like what they used at the factory, but everybody in the field is using a 1-1/4" grade 5 bolt that has a 3/8" long solid collar above the thread, as shown in the pic from my last post.

That is what I found at my local supplier, so for now that is what I'll go with. Perhaps the fully threaded shank is weaker/too weak..

You might have to look for "machine screw" because they are threaded all the way to the head, typical use is in a tapped hole.

KC

 

[lpakiz]

When you replace the shear bolt, try to work some grease into the tiny space between the spinning shaft and the now-stationary hub, or drill and tap a grease fitting into the hub.
My auger shear system is the older, hub/shaft shear style and my hub has a grease fitting on it, to prevent the grinding and galling that will occur when the shaft is still turning and the (dry) hub is stationary.
As long as the bolt is driving the two pieces at the same RPM, no grinding occurs. As soon as you shear, that changes.
That snap ring may be to keep the shaft and hub engaged and in position if the shear bolt is no longer doing that.