3PTH hitch Blower vs Front snowblower

[asgard]

I see a lot of badly maintained old and abused walk behind blowers. They are given no maintenance, left outside all summer and then expected to work in cold, harsh conditions, which in my experience they generally do.

It is not that expensive to rebuild a front gearbox on one, the gear is brass/bronze and is potentially a sacrificial item to save the main gear and shaft.

I owned an allied rear blower, built like a battleship and had a gearbox and external chain drive, you still needed to lubricate the chain, the nylon tensioning roller needed some work and so did the gearbox. You could still break a shear pin and there was alway the chance of it not breaking and the rear PTO taking a hit, now that I would think is some work.

I think they are heavier in part to stop them lifting when backing into banks, I know my B 2301 has no rear down pressure so dead weight is the main factor in operation.

I think most of the statements made by the original poster are scare mongering.

Keep calm and snow blow anyway.

 

[tcrote5516]

I think that the worm gear design is good for smaller applications, but as it gets scaled up, you can't really make the worm gear beefy enough without it getting too big and getting in the way of the snow that's headed for the impeller. Using belt drive gives the drive train also gives the drive train the ability to absorb a bit of shock so that you're not relying entirely on the shear pins. PTO shafts don't have much ability to absorb shock.

I don't know about that theory....here's a worm gear rated for constant duty at 2754Nm of torque. That's over 2,000 ftlbs of torque and they make them bigger than this.

https://www.alibaba.com/product-detail/Big-Torque-WPW-Cast-Iron-Worm_60336956056.html

 

[bucktail]

I couldn't find the dimensions for it but it seems to me that if you went too big it would get in the way

 

[bucktail]

Probably more importantly, the worm gear is fully supported by rotating shafts rather than being mounted to a frame or plate. The auger shaft holds against the torque of the impeller shaft and the impeller shaft holds against the torque of the auger shaft. The weight of the gear box is supported by some combination of the shafts. The bigger the blower gets, the bigger the worm gear box needs to be, and the further it gets from the bearings that ultimately support it.

 

[pak]

Dave, Since I have one of the blowers in question, my take away from your comments is to insure I'm using the correct shear bolts. Yes?

 

[Dave_eng]

pak

To respond to your question, I think it best to do the following first.
Post a picture of the fan and hub area so we can see what style you have.

Next remove the shear bolt and rotate the fan just enough so the two shear flanges are visible like in this photo.

What we need to see is the condition of the hole in each flange.
Some owners, depending upon which side they put the shear bolt in from, may have one or the other shear flange holes out of round.
It is likely in this photo that the grade 8 shear bolt from Kubota had too many threads and the bolt was shearing in the threads which tore up the hole in the fan flange.

I don't understand what I am seeing in the fan flange where I have drawn a red line and have asked the owner to take a closer look,

Dave M7040

 

[pak]

I took a look and the bolt holes are fine. I'm sorry but I don't follow your point. Are you suggesting the bolt grip is the wrong length or the bolt grade too high?

 

[Dave_eng]

pak
I am trying to find the broken bolt photos from the owner in Alaska as it will make explaining my point so much easier for you to understand...

The issue of which grade bolt is confusing. First confirm what style of shear bolt at the fan.

I had suggested you post a photo of your machine. If you are not certain how, it can be easily explained to you so don't hesitate to ask.

For now I am going to post the two styles.
Photo 1 original style

Photo 2 better style

I will be back as soon as I locate the broken shear bolt photos

OK back

First photo is of a broken grade 8 bolt provided to the owner of a blower with the second photo design.

Look at where the shear bolt fractured, in the threads. The threads of a grade 8 bolt are like a metal file and rip metal from the hole in the flange surrounding the threads as it shears off.

The photo of the second grade 8 bolt which is not broken was removed from the blower before it broke. Again see the damaged threads from the shear flanges trying to shear the bolt.

Although the shear bolts are given to this owner for his blower, they appear to be the wrong length if not grade.

The threads should not start until the shank of the bolt is just out to the outer edge of the flange. The part of the bolt trying to be sheared should be the smooth shank.

The shear bolt should be torqued properly to pull the two flanges together so they act like a pair of new scissors cutting heavy paper not like a worn out pair where the connection between the two blades is floppy and loose and you cannot cut paper.

You need to use a washer or two before putting the nut on the shear bolt. The reason is to allow the nut to pull the flanges together without running out of threads and starting to come up against the smooth shank. Should the nut come up against the smooth shank you will get a resistance to turning the nut which is because there are not more threads rather than because the flanges are being firmly squeezed together.

In summary, I would not use grade 8 bolts but follow the instructions on this package.

For the fan shear bolts which are the smaller shorter ones, you don't need to buy them from Kubota. Any hardware store 1/4" bolt with no radial lines on the head will do. Make certain it is long enough that there are no threads within the two shear flanges and use washer(s) to make certain the nut can squeeze the flanges together without running out of threads. Use mechanical locking nuts. These nuts are deformed to resist unscrewing. Tighten a second nut against the first to help ensure it does not move. Do NOT reuse lock nuts!!

Engage your blower at a low rpm and them increase the speed to achieve the rpm likely marked on your tachometer for the proper pto speed. It wont be wide open throttle but close to it.

Pay attention to the proper roundness in the shear flange holes. If the bolt is a sloppy fit in either hole this condition needs to be fixed. Alternate which side you insert the bolt through the two flanges to even out any wear.

Dave M7040

 

[North Idaho Wolfman]

I don't know about that theory....here's a worm gear rated for constant duty at 2754Nm of torque. That's over 2,000 ftlbs of torque and they make them bigger than this.

https://www.alibaba.com/product-detail/Big-Torque-WPW-Cast-Iron-Worm_60336956056.html

While the worm gear your pointing out is a extreamly high torque model, I don't think the brass gear, aluminum cased, box can come anywhere near those torque values.

 

[tcrote5516]

While the worm gear your pointing out is a extreamly high torque model, I don't think the brass gear, aluminum cased, box can come anywhere near those torque values.

I agree but if you read the original comment that this was in response to you'll understand the relevance. It was a response to a question of scalability of the worm gear arrangement and not a comparison to what's used in a snowblower.

 

[pak]

Dave, Thank you for taking the time. My blower, after about 40-50 hours of use looks brand new. I have sheared several auger bolts but never one of the fan shaft bolts. I completely understand the grade and grip length considerations. My confusion developes when this shear bolt issue is placed with the context, of your original posting, of not recommending this style of snowblower. Thanks again, pak

 

[torch]

Back to the original question...

I am the first place on a private road shared with 2 others. I look after the road from my place out to the main road, then the next guy handles from his place to mine and the last guy clears the remainder to his place. I have an older Kubota with 3ph blower, #2 has a Yamaha 4 wheeler with plow and #3 has a 2 year old B2620 with front mount blower.

This year in particular, #2 has required some help. He just doesn't have anywhere left to push snow nor the power to push it further. #3 has helped and I was over there yesterday blowing the banks back into the bush for him. That's when I found out that both #2 and #3 say my machine does a better job -- particularly, scraping down to the base and leaving a nice level and even finish, but also the ability to cut into and remove the plow windrows.

Given the B2620 is bigger, heavier and more powerful than my old B7100, any advantage must be in the blower itself. The 3ph blower is made of heavier steel (generally twice as thick) as the front mount, and I suspect that extra weight is the biggest advantage. The additional rigidity can't hurt either.

So, while I can't say which one throws snow further, it appears that the 3ph blower can do a better job in adverse conditions.

Too bad the 3ph requires twisting around facing backwards to use it. That is a huge drawback as it is sooo awkward.

 

[North Idaho Wolfman]

The 3ph blower is made of heavier steel (generally twice as thick) as the front mount, and I suspect that extra weight is the biggest advantage. The additional rigidity can't hurt either.

That is only half true, they do make the same blower for the front and rear, but it's a better, heavier built model with a heavier price tag and so most opt for the lighter, cheaper home owner version over the heavy commercial version.

You also can make just about any 3 point blower work on the front, it just needs the right gear reduction box to make it work with the higher MM PTO speeds.

It's all in what you buy and how you equip it.

 

[tcrote5516]

It's too bad they don't sell a 3pt blower that's as expensive as a front mount but comes with a swivel seat, a second steering wheel and hst pedals.

Then we'd really have a debate on which was better

 

[Dave_eng]

Dave, Thank you for taking the time. My blower, after about 40-50 hours of use looks brand new. I have sheared several auger bolts but never one of the fan shaft bolts. I completely understand the grade and grip length considerations. My confusion developes when this shear bolt issue is placed with the context, of your original posting, of not recommending this style of snowblower. Thanks again, pak

Pak
Let me try and clarify exactly what my position is on the worm gear front mounted RAD blowers.
It is a big pause in the acquisition of one until such time as Kubota, its dealers in Canada and USA and RAD have the same consistent advice and solution for owners of this product. No doubt they will reach that point but why not find an interim solution, as a purchaser, until such time as the final solution is found and implemented on the product you want to buy. For the purchasers of used equipment the choice is even tougher. The product is already built. You could be one of the lucky ones with this product, like those who don***8217;t accept my reservations, or perhaps you might join the unsatisfied ones. I don***8217;t know what the odds are in you ending up happy but I do know it is not 100%.

When the owner of an F2100 was considering fitting a B2771 (I think that was the number), Wolfman cautioned him against doing so. Why because it is a more powerful machine than a BX so the blower would be driven into banks of snow with more force than a BX. Its pto turned with more torque. He further said there were products made for either front or rear installation which were more robust.
I understand, if you are the proud owners of a machine with the style of blower I am suggesting a pause on, it is your pride and joy and seeing it portrayed in a less than stellar light hurts.

A parallel situation may, as I explain it, assure you I get how it feels. Often friends ask for my opinion on a home they want to buy. If it is their first time, they usually ask for my advice after they have fallen in love with the home. My role, in their minds, is just to reinforce the decision they have already made emotionally. When we arrive at the home, they want to take me to see the great kitchen or bathrooms. I insist on starting in the basement and they are puzzled. Often, after spending time in the basement I don't even bother to go to the other rooms. The home has too many issues and my friends, who will be just able to pay the mortgage, will have nothing left to replace the electrical, plumbing and mechanical system. They are badly hurt and initially a bit pissed with me. By the time they have found the next home they have learned to not commit their hearts too soon. They wait to do that until I tell them this one is a low cost maintenance one and then they commit to it totally.
Hope this clears up any lack of clarity in where I stand.
Dave M7040

 

[North Idaho Wolfman]

It's too bad they don't sell a 3pt blower that's as expensive as a front mount but comes with a swivel seat, a second steering wheel and hst pedals.

Then we'd really have a debate on which was better

They kind of do, look at the F series!

 

[tcrote5516]

Dave it seems as if rather than an explanation of your position that was a dissertation regarding others who don't agree with you being blinded by their emotional attachment....to an attachment. We are happy with our blowers performance, we are not in love with them or in denial. We won't let them beat us with their chutes and then tell our wives who notice the bruises that it only does it because it really loves us back....

As an actual owner I have ZERO, NADA absolutely NO confusion as to the sheer bolt needs or how to find them. It's clear in the manual. Its on a giant sticker on the blower itself and available at dealers or a dozen online retailers.

If you want a complaint and something that is actually a REAL problem I have one. The paint; it's terrible, it chips, it sucks.

But mechanically, no issues and I say that as a matter of fact not because I take my blower to bed with me out of a deep love though if the paint was better...

 

[tcrote5516]

They kind of do, look at the F series!

HA! True.

Wonder if someone on a F series forum is day dreaming about a rear FEL option to complete the circle.

 

[North Idaho Wolfman]

A parallel situation may, as I explain it, assure you I get how it feels. Often friends ask for my opinion on a home they want to buy. If it is their first time, they usually ask for my advice after they have fallen in love with the home. My role, in their minds, is just to reinforce the decision they have already made emotionally. When we arrive at the home, they want to take me to see the great kitchen or bathrooms. I insist on starting in the basement and they are puzzled. Often, after spending time in the basement I don't even bother to go to the other rooms. The home has too many issues and my friends, who will be just able to pay the mortgage, will have nothing left to replace the electrical, plumbing and mechanical system. They are badly hurt and initially a bit pissed with me. By the time they have found the next home they have learned to not commit their hearts too soon. They wait to do that until I tell them this one is a low cost maintenance one and then they commit to it totally.
Hope this clears up any lack of clarity in where I stand.
Dave M7040

I can totally relate, Oh I don't even want to admit to how many words and objects have been thrown at me when I go to do a remodel and I turn it down because there really isn't anything I can do to save the "Wonderful Home" they want remodeled!

 

[torch]

That is only half true, they do make the same blower for the front and rear, but it's a better, heavier built model with a heavier price tag and so most opt for the lighter, cheaper home owner version over the heavy commercial version.

You also can make just about any 3 point blower work on the front, it just needs the right gear reduction box to make it work with the higher MM PTO speeds.

It's all in what you buy and how you equip it.

My experience with the various Kubota-branded blowers is very limited. My B2550 clearly has an add-on speed reduction chain drive and I suspect the same basic design could be/was marketed as a lightweight 3ph blower with a suitable mount.

This does imply that my B2789 3ph blower could be fitted with a similar speed reduction and bolted to the front with a suitable mount. But I don't think I would want that much weight hanging on the front of the tractor, not without a pretty substantial subframe added, anyway.

If Kubota offers a heavier-duty front mount blower for their compact tractors than the one's I've seen thus far, then it might well be worth considering even for heavy use applications. This lookiing over my shoulder for 2 or 3 hours is getting old fast!