[Lochinvar]

Hi All,

I have a question for those wiser in the ways 37A snowthrowers than I am. Today, when we were graced with a meager 2 inched of snow, I jumped on the chance to get some seat time and run my '71 112 with the thrower for about the second time this snowless season. We live very much in the city, and one rationalization I use for running my rig at all is to clear all the way around the block, rather than just our corner lot and driveway.

Evidently I let the pent-up joy at blowing get the better of me today and while clearing on the far side of the block, I hit something covered in the snow which locked the rotating blades up completely. Lo and behold, after shutting things down and looking peering into the situation, I found a chunk of the side of a concrete block (!) wedged between the impeller blade and the scraper blade and housing.:sad_02:

Then, cursing my situation and wondering if a neighbor decided that sabotage would be amusing, I freed the block from the blower, fired the machine up again, and engaged the PTO...and wonderfully, all functioned as it should. The only immediately visible damage was an indentation on the impeller blade.

I plan to put rubber flaps on the impellers next year, so I am less concerned about that than I am a tendency for the rotating blades to move on their axis when the power is off and the 37A is at rest. I noticed this when I was cleaning the interior of the housing and the blades after I finished up the block's sidewalks, and I have not had this situation before.

Have I sheared a shear pin? Or is this a sign of something more grim? The thrower cleared well after the incident, and did not seem to have a loss of velocity (such as it it) through the chute.

Thanks for any advice!

Lochinvar

 

[slkpk]

Sounds like you got lucky and had fun to boot. slkpk

 

[Harryc]

Have I sheared a shear pin? Or is this a sign of something more grim? The thrower cleared well after the incident, and did not seem to have a loss of velocity (such as it it) through the chute.
Lochinvar

It would not throw snow if it sheared a pin. Enjoy the winter!

 

[HydroHarold]

Since IT DIDN'T SHEAR A PIN, if it were me I'd wanna know "why not?"!!!! A block of concrete that will stop the impeller dead should have sheared the pin to protect the drive system.

"wondering if a neighbor decided that sabotage would be amusing"

Could be the impeller and shaft are locked up-rusted together and the next time you encounter this kind of neighborly entertainment it could be a very bad outcome. I don't really call you "lucky" until I know it WILL shear a pin the next time.

 

[Harryc]

I don't really call you "lucky" until I know it WILL shear a pin the next time.

Good point. :thThumbsU

 

[gray wolf]

I did the rubber flap conversion.100 percent better on the 318.that,s not saying a whole lot.eight feet or so before.to be fair snow was very dry.have to agree with why did,n it shear a bolt.

 

[PA318Guy]

My guess is that you did shear a pin and that there's enough rust build-up on the shaft that the 2" of snow didn't cause it to stop spinning. Check your shear pin, it should be broke.

 

[littletractorguy]

Yes, I agree, since my 38 on my 160 sheared a bolt without hitting ANYTHING (as far as I can tell), I'd be very curious as to why yours DIDN'T shear... Although I suppose its possible that having it wedged in like that, it brought your blower to a halt "relatively" slowly... if the piece of concrete got dragged a ways before it wedged firmly. However, having it still spinning when the blower's not engaged, yes, that sounds like your pin is gone....

 

[Lochinvar]

Thanks to all for the counsel! I definitely have some pin checking to do tomorrow. Rust freeze is a sure possibility, as this was not the best maintained thrower when it came to me. . .

Lochinvar

 

[dsouthw524]

If it didn't shear the pin, check and see if the previous owner put a hardened replacement in there. He might have because he did not know better and kept breaking pins.

 

[Lochinvar]

Curioser and curioser. .

After taking everyone's advice, I ordered more shear bolts from my Deere dealer. When they arrived today, I pulled the bolt that was in place and installed the dealer specified ones ordered off JDparts.com.

The bolt that I removed, that did not break, had no markings on the hex head, so I assume it was a correct grade for a shear bolt. It was, however, very much tightened down, completely so, with a standard nut. When I pulled it off, the auger rotated freely as it should. Then things got interesting:

- with the new shear bolt in place, and not completely tightened flat but using a lock nut I find that with enough force, I can rotate the auger. This in turn rotates the thrower's drive wheel and the PTO belt. This means I have some damage to the thrower drive, I think?

- the bolts sent from the dealer seem to be Grade 5s: three line marks on the lower half of the hex, and "NORM" on the upper half. I assume (doing a lot of that with this situation) that the NORM is the manufacturer, but I am most concerned that the bolts are too strong a grade for shear placement in a 37A.

Has anyone else found or used these bolts? Or have I just set myself up to re-mangle whatever I mangled when I hit that block?

As it happens I have cleared away 2 inch snowfalls twice since posting, with no apparent thrower problems.

Thanks again!

Lochinvar