Unbelieveable - small rant on snowblower

[smfcpacfp]

dmcneil had some good ideas of things to look for, after all he had to defend the honor of our North American neighbors.

Since the shear bolts are breaking, there is another problem. Shear bolts only solve the problem of hitting blunt things.

I have been snowblowing for close to 30 years and I have learned a few things. One thing I have learned is that it doesn't pay to stress the equipment. Someone of this forum once told me that the best way to use a snow blower was to push it hard. I believe he was from Virginia. As a yooper, I don't take snowblowing advice from Virginians.

As the snow gets deeper and heavier I take smaller cuts with each pass, and go slower. I don't want to hear the engine labor anymore than when I have six inches of snow at 10 below zero (you can clear that snow with a leaf blower). It takes longer, but having to rebuild a gearbox wastes a lot of time and money.

Are you pushing your machine too hard?

 

[DGS]

I have a Meteor and the gear box suspends both the PTO shaft and the fan all in the same package so it could have something to do with that
It definetly could be a weak point if bearings,adjustment of shafts etc are not up to snuff
Also be careful of your PTO angle when fully raised
Good luck and please keep us posted
Don

 

[StrangeRanger]

It will be interesting to know what happens with the grade 2 bolts. If the shear pins aren't breaking is it reasonable to assume that the stress is within the gearbox itself? Or perhaps another way of thinking of it... why isn't the stress on the shear pins?

Sure wish we could help..

That's why I said it's not the greatest design. On the chain drive side of things the shear bolt does take the brunt of the impact. The shear bolt is between the auger and the gearbox. But, that only helps when the auger hits something. If something hits the fan the forces are transferred first to the fan shaft/gearbox, then up the PTO to the shear bolt on the tractor end of the PTO shaft.

In this instance neither shear bolt broke. If I have time to get into it tonight I will post some pics.

 

[slewisma]

Kubotafan: prior to running the blower the week before I removed all the sheer bolts to check them, lubed everything, inspected/greased/tensioned the chain drive, made sure the gearbox was full of lube, checked the cable to rotate the chute ... basically went over the whole thing w/ a fine tooth comb.

Just to be a contrarian for a minute, might you be put too much lube or too high a viscosity lube in the gearbox? A lot of think lube out in the cold temperatures could be bogging the gearbox down fulltime?

Probably not the cause but might be worth checking.

 

[StrangeRanger]

Just to be a contrarian for a minute, might you be put too much lube or too high a viscosity lube in the gearbox? A lot of think lube out in the cold temperatures could be bogging the gearbox down fulltime?

Probably not the cause but might be worth checking.

It was the recommended weight lube and you can't over fill it because the check/fill plug is about 1/2 up the side of the gearbox. You simply pour it in until it starts to come back out and pop the plug back in. Plus, it wasn't that cold out and when it came spilling back out it sure was in good shape
j

 

[slowzuki]

He's not having a lubrication failure here. Laurin snow blowers and a number of others are built in the exact same fashion. I'm wondering if its a bad batch of gearboxes.

The shear bolt on the auger is not just for auger protection. If the fan hits something and jams the interia of the auger keeps trying to drive the gear box since there is no over running clutch. The shear bolt on the pto shaft protects the tractor's pto more than the blower.

Thinking now too, I wonder if your impeller is out of balance too?

My Laurin blower has hit so much garbage in the last 30 years there is about 1" of clearance at the tips of the impeller and 1/8" grooves in the housing for it. At least it doesn't break many shear bolts now, even when blowing crushed rock.

 

[canoetrpr]

SR - last few times I have broken the shear pin on the pto shaft, a piece of wood has gotten entangled into the fan. So that shear pin has broken for me appropriately before the gear box gave out.

Now I don't mean to suggest that the design is robust or not - I frankly have not analyzed it at all. However it is held up to what I have put it through (so far!)

 

[638]

I suspect the problem was caused by not running the blower fast enough. You stated you were runing at a reduced RPM when both gearboxes failed. I think that running at to low of an RPM over loaded the box and caused the failure. Blowers depend on high RPMs to be efficient and are designed to run fast.

 

[radioman]

I suspect the problem was caused by not running the blower fast enough. You stated you were runing at a reduced RPM when both gearboxes failed. I think that running at to low of an RPM over loaded the box and caused the failure. Blowers depend on high RPMs to be efficient and are designed to run fast.

oh come on. you really think that babying our equipment will cause early failures ? if anything it should prolong the life.

 

[escavader]

I have a Meteor and the gear box suspends both the P
Also be careful of your PTO angle when fully raise
Don

I think that is a possible cause of the faulure right there!If the pto shaft was cut wrong and it was to even slightly bottom out on itself ,when youve raised the blower up,it would break something at the weakest point,which would be the tractor tranny housing or the gearbox,which ever is the weakest.You might not even know its doing it if the sheild is in place.Id definately take off the sheild,reinstall the pto shaft lift the implement up to your tractors highest position,and see if your bottoming out your pto shaft. that would snap thet gearbox on the blower like a twig.
Who originally cut the pto for your tractor when you got your blower? Each implement should have a special cut pto shaft for proper slippage.
ALAN