Shear bolts on snowblower fan keep snapping - Page 4

OldSkull · #31 01-24-2016, 04:59 PM

Something is terribly wrong! Never seen a Berco eating shear bolt like that before and I have seen a lot since they are build in my neck of the wood.
(They build them for Kubota too)

-In the troubleshooting section they say "The head of the bolt must be on the right side"

-Looking at the diagram, if this shear bolt is broken the fan and auger are both stopping to turn right? If it's the case I check the chain tension of the auger or for anything getting stock or very hard to turn.

-In last resort check your model+serial number and call Bercomat.

DoubleO7 · #32 01-24-2016, 05:46 PM

Make sure the holes in all the parts the pin is passing thru are round, the same size as esch other and very close to the size of shear pin. Any hole that is larger will allow that part to "hammer" on the shear pin.
Look at the pins that are sheared and the oversize hole is in the part the coincides with the sheared spot of pin.

seanmmcc · #33 01-25-2016, 01:12 PM

Thanks. I called berco today and they think it might be a loose shear plate. You can see it listed as part 18. He didnt seem to care about slop in an out but more left to right.

https://drive.google.com/file/d/0ByH...ew?usp=sharing

I am going to see how much play is in the plate and see if there is any way to tighten.

Thanks

Sean

DoubleO7 · #34 01-25-2016, 02:51 PM

He is suspecting the key in the shaft going into the shear plate #18 you speak of.

seanmmcc · #35 02-08-2016, 03:20 PM

We have snow coming tonight so hopefully will be able to test tommorow. I bought a new key, per recommendation and it was only 2 bucks. I also got some locktight I am going to put that and the key in tonight and see how it does tomorrow.

Sean

seanmmcc · #36 02-16-2016, 02:19 PM

I put the new shaft key in and replaced the shear plate. With the lock tight it stays tight and there is no slop in the shear plate/shaft now.

BUT....

I keep breaking shear bolts. Last nights snow was heavy wet 3" and still went through 3 of them. Again Im not hitting anything it just seems like time and then they break.

My new assumption is that the hole in the gear where the shearbolt goes through is causing play and breaking the bolt.

Here is a pic of the worn hole. I would bet the bolt has 1/8 of play in the hole now that it is worn.

The second pic is the shear plate with the shear bolt going through the plate and gear.

Should I just turn the gear and drill a new smaller hole?

Thanks

Sean
(buying stock in #8 shear bolts)

Sam Mac · #37 02-16-2016, 02:30 PM

If it was my blower I would do 1 of 2 things, turn the shear plate 180 degrees and drill a new hole in the sprocket or drill both the shear plate and sprocket with a larger hole for a larger bolt. Make sure that what ever size you go to that the bolt is a snug fit.

Berwil · #38 02-16-2016, 02:42 PM

What if you rotate the sprocket 180 degrees and use the new shear plate as a guide to drill a new properly sized for the shear bolt. This is assuming the sprocket is drillable.

Bill

Edit: got side tracked between preview and posting and Sam beat me to it.

DoubleO7 · #39 02-16-2016, 03:13 PM

If the shear bolt is wallowing out the sprocket, my guess it is also drillable.

seanmmcc · #40 02-16-2016, 04:15 PM

Thanks for the feedback. If I spin this 180 and drill I assume I will mark the spot through the shear plate hole. And then drill. The shear plate doesnt have too much play so I guess I will keep to a #8 size.

Any idea what drill bit I should use? I am looking at this chart. It appears to be a #29?
http://www.lincolnmachine.com/tap_drill_chart.html

Thanks

Sean