Operating 3 point blower in raised position- why not?

[SuperiorLakeEffect]

Hi folks, new member here. Bought a house last year with a 1/3 mile gravel driveway. Managed to keep it open last winter with a big old ariens st1236 and tired old jeep cherokee plow rig, but it was always a hassle.

So this winter I upgraded to a Kubota L3901 with a SB1064 rear 3 point blower.

I've always been super careful about building up a snow mat before when using my old walk behind and have managed to never bust a shear bolt. Have been contemplating my snow removal strategy for this coming winter. Was hoping I could just run the blower with it raised 3-4 inches off the ground and then pack down the remaining snow by driving over it. Unfortunately, the manual states that operating the blower in this manner is bad and to only blow snow with it fully lowered.

OK, got it. Won't do that then.

But I'm curious as to why?- just want to understand the forces at work here so I don't do something else dumb. Can anybody enlighten me?

Thanks!

 

[Peter 315]

I guess the pto shaft.....:2cents:

 

[CobyRupert]

When the blower is down, I think the pto is actually at a worse angle and gets better (straighter, more horizontal) when it’s up 3”-4”? If so I wouldn’t worry about it. It’s not like you turn blower on/off every time you raise it?
Note, by being lifted, your front end is lighter, and steering less likely to grip. Even though you’re carrying more weight on rear axle and have better rear traction, you might need it when driving through 4” of snow instead of a cleared path. Perhaps these are reasons manual says to lower blower.
Or, lower the skid shoes on the blower so that the cutting edge is 3”-4” above ground, and weight of blower is on ground.

 

[PILOON]

OK, I have maintained a gravel drive for 25 years so a few tips.

First off lower the skids or shoes to leave one or 2 inches of snow.
Driving on that will form a base after which you can re set the shoes/skids.

Another modification I did was to weld wider longer bottoms on my skids* as I found that the factory skids on un frozen base would stir up stones as the narrow factory ones simply plowed ruts.
No problems now. (only replaced 2 shear bolts all last winter!)

In fact neighbors asked me to also create wider skids for their blowers,

(I now only shear a bolt if and when the city plow buries a stone in the entrance pile as he passes by.)

* I made mine about 10 inches long X 2 wide with both ends turned up like small skis.

 

[Gordon Gould]

I would guess, and it is a guess, that the clevis connections on the blower where the tractor lower lift arms attach are not designed to hold the weight of the blower plus it's load of snow along with the vibration when it is operating.

gg

 

[SuperiorLakeEffect]

OK, I have maintained a gravel drive for 25 years so a few tips.

First off lower the skids or shoes to leave one or 2 inches of snow.
Driving on that will form a base after which you can re set the shoes/skids.

Another modification I did was to weld wider longer bottoms on my skids* as I found that the factory skids on un frozen base would stir up stones as the narrow factory ones simply plowed ruts.
No problems now. (only replaced 2 shear bolts all last winter!)

In fact neighbors asked me to also create wider skids for their blowers,

(I now only shear a bolt if and when the city plow buries a stone in the entrance pile as he passes by.)

* I made mine about 10 inches long X 2 wide with both ends turned up like small skis.

That's what I do with my plow truck- I have some plow shoe attachments welded to a pipe that runs along the bottom of the plow. Can happily plow away right from the get go without tearing much up. I've got the inner shoe attachments on the way, might try something similar with this.

I would guess, and it is a guess, that the clevis connections on the blower where the tractor lower lift arms attach are not designed to hold the weight of the blower plus it's load of snow along with the vibration when it is operating.

gg

That's kind of what I'm figuring, or there are some torsional forces that might twist things up when it's not resting on the ground.

I don't think it is anything PTO related as the manual also states it is fine to leave the PTO engaged when driving forward with the blower raised (as long as it doesn't exceed the PTO shaft angle specifications).

 

[seville009]

leaving it raised shouldn’t be an issue. I used to do that when blowing on grassy areas, or even on asphalt when the snow is really wet and heavy underneath.

The only other downside would be that the layer you leave on the ground might freeze up and hard to scrape off later, but in your case, you’re actually trying to do that with the gravel drive.

 

[PILOON]

Commercial guys drive around all day with blower engaged and in raised position.
In fact the Ujoints like it better since raised is more in a straight line.

In my case the only time I disengage is to clear up a clog or to replace a shear bolt.

 

[RoyJackson]

I have used the 3PH blower raised on occasion...mostly to remove piles of snow pushed by the town snowplow. He doesn't do a good job clearing the snow most of the time.
When I write I run it raised, it's normally about a foot off the pavement. So far (knock on wood), no problems.

 

[oosik]

When I had a blower, I lowered the skids to the point that the drive shaft was almost a dead straight shot. Yes - I had to instal wider skids. I couldn't always wait for the driveway to freeze up - hard as a rock. The OEM skids would dig in and pretty soon - I was blowing gravel. The wider skids kept the blower on top of the partially frozen gravel.

Actually - it didn't make a whole lot of difference. With the lowered, wider skids I left about two inches of snow on the ground. My driveway is a mile long - gravel.

JMHO - having your blower firmly on the ground will lessen/eliminate torsional problems. This should only be a problem for your 3-point arms and not the blower or PTO shaft.