Single Stage Thrower, advice needed

[Hydro 131]

I recently bought a 1994 tall chute single stage snow thrower, model 79360.  I have replaced the chain, both idler sprockets, both idler pulleys and one jack shaft bearing on the chain side.  The auger is strait and the bearings are smooth.  It runs quietly.  I have it mounted on my 314H powered by a Kohler M16.  I am shearing the pulley key on the jack shaft.  It has happened twice now.  The first time it threw the set screw so I thought it was a matter that the screw was not tight enough.  Toro shows one screw although the pulley is drilled and tapped for two.  I was careful I thought when I positioned and tightened that screw.  After the first time, 20 minutes running, I added the second screw.  I also noticed the pulley has some wobble to it so I used some shim stock in order that there would be no play between the shaft and the pulley.   I ran it for about 20 minutes again and noticed both screws were loose so I used Loctite 242.  I let that sit for about 30 minutes and went out again.  In about 20 minutes I sheared the new key right off with a portion of it in the keyway of the pulley.  The shaft is clear of the key but has been scored some.

My driveway is paved.   I was plowing before and built up some snow banks.  The first time I sheared the key, the thrower was mainly resting on the scraper blade and I was just removing snow from the driveway, I thought I might have jammed it with some ice.  The second time I raised the thrower to give it clearance so there was about 3/8†between the blade and the runners which I adjusted.   

I ease the machine into snow and creep along.  I do not ram it into snow banks.  I’ve seen videos of these things working really well.  Mine was blowing snow beautifully but something is not right.  Is it the fit between the pulley and the jackshaft?   Why would Loctite not hold the set screws? What is wrong with my machine or what I’m doing wrong?

I have to suspect there is a weak point where something will give or the belt will just slip.  My belt is new and has the correct Toro Part number.  It fits the way I have seen them mounted so I doubt that has any part of what is happening.

I would appreciate your thoughts. 

Thanks

Gary

Edited December 27, 2013 by Hydro

[Lane Ranger 10,968]

The pulley sounds like your culprit here.  You should not have to shim it.  The  pulley may have gotten out of round where it meets the shaft .  If you used shims that suggests that is the problem to me. 

[rayshorses 102]

If the pulley has any wobble or is loose fitting , that will cause it to shear the key. You might want to replace the pulley. It needs to run smooth and true because of the high rate of speed and torque applied , the wobble will cause a vibration that will cause it to fail. Did your belt whip much?...it shouldn't.

[dbartlett1958 96]

Gary,

 

My driveway is NOT paved, and I have a fair amount of crushed rock around as well thanks to the guy that built the place. Regardless, I have shot a lot of rocks and ice chunks through my single stage blower with absolutely no issues regarding keys, keyways, or pulleys, so I will agree with Lane that it is probably an issue with the fit between your pulley and shaft.

 

Once you get it sorted out, you will really like it.

[squonk 41,051]

I have a Tall shoot ss blower with a gravel drive. I haven't used it much. Last year it was used for moving piles back and threw lots of stone that was in them. It rumbled some so I tore it apart this summer. I replace the chain idler sprockets and jack shaft brgs. Now it sounds like a tornado coming through. I don't know if that's normal or not. Click on the pic

 

Edited December 28, 2013 by squonk

[RMCIII 838]

I've noticed that several of the single stage blowers have a sound of their own... Mine also sounds similar to yours Mike. Not quite as loud, but definitely has a hi-pitched whine to it. Replaced all bearings, idler sprocket, and belt. I use Lucas chain lubricant, and belt conditioner. I wish mine did not have the mule drive in the front of the blower. What has happened with mine is the belt fraying on one side due to the angle of the belt coming off the shaft pulley. Chain is lined up correct, so the entire shaft is where, it is supposed to be riding within the floating bearings. I have moved the pulley slightly off the shaft to help reduce the fraying. But I can tell it is still an issue.

[MalMac 1,331]

Like said start with replacing the pulley. That is the part that has an obvious flaw. That pulley spins at such a high rpm that any wobble or out of balance will cause vibration and vibration at a high rpm turn in to an ultra sonic type of thing that can cause failure. The pulley and belt can appear to be in perfect alignment but when spinning can also become out of alignment do to things not holding tight then come back in when you shut it down. We had an old combine that would do that. Pulley would walk on the shaft when in motion and straighten back out when shut down. Sheared keys and ruined bearing before we could track down it was trying to walk on the shaft and it was not turning near the rpm your blower is turning.

[Kelly 1,029]

I agree bad pulley, but if the pulley has spun on the shaft even a little the shaft may be no good, the pulley should be a tight fit on the shaft, I anti seize my pulleys and have to tap them in place. I have welded the pulley to the shaft before to get by, and later replaced the parts, be sure to get the right parts the tall shoot blowers are heavier duty than the older ones, with grease able bearings and bigger shafts

[Hydro 131]

Thanks very much everyone for your input.  Thanks Lane Ranger.

 

I'm ordering a new pulley on Monday.  I hope the jackshaft is okay, the keyway is still clean and the marks are not deep so hopefully it will be okay.

 

rayshorses it was your video I just watched which told me I was not pushing the blower too hard.  I was not doing anything differently than what I saw you doing and yes I was a bit surprised at the belt movement sometimes when under load.

 

Dave thanks for your input.  I really do like this unit over the 2 stage.  Much easier on the tractor and me  I ripped a newspaper through it yesterday, did not know it was there.  No issue with that at all.

 

Mike thanks for the video.  I saw another one on You tube as well.  My thrower does not have quite as high as pitch whine to it but the auger bearings are fine so maybe its just a different noise.

 

RMCIII the key way cut on the jack shaft is pretty wide.  You should be able to align the drive pulley with the PTO and the two idlers.  I had no problem doing that with mine.  I do not have any issue with belt deflection.  Is the Hub on your pulley facing inwards?  

 

MalMac thanks.  I think that's the problem.

[Hydro 131]

I agree bad pulley, but if the pulley has spun on the shaft even a little the shaft may be no good, the pulley should be a tight fit on the shaft, I anti seize my pulleys and have to tap them in place. I have welded the pulley to the shaft before to get by, and later replaced the parts, be sure to get the right parts the tall shoot blowers are heavier duty than the older ones, with grease able bearings and bigger shafts

Thanks Kelly.  I have the Toro Parts Finder and have actually looked at all the changes from 1993 through to 2001 for my model.  What I noticed was the bearing keepers had zerks on them but they go over a sealed bearing so I'm not sure what that was intended to accomplish.   I also noticed they added a metal shroud around the lower front of the chute to get more distance but otherwise I think as far as the tall chute models go they stayed pretty much the same.

I hope you're wrong about the jackshaft but given your experience you probably aren't   so that will be another $200 bucks.  I guess any play is too much.

[shorts 182]

The grease zerks in the mounts for the sealed bearings are to keep/flusk the snow and ice away from the seals on the bearings, just an added later of protection for the bearings.  If your shaft is damaged you might want to look into a generic shaft from a bearing or industrial supplier, different diameter shafts are available, some with a keyway cut full length in 3 or 4 foot lengths, all you have to do is cut to proper length and install

[squonk 41,051]

We use cut shafts from McMaster-Carr all the time at work.

[RMCIII 838]

Gary - I wish that was the case. Mine does not have a straight line to the pto. Mine comes off the front, in order to get the belt to align correctly, the pulley would need to be almost completely off the shaft. I think it is just a poor configuration of the mule drive.

Thanks though.

[Hydro 131]

Thanks Shorts and Mike.  That's something I'm not familiar with but glad you drew it to my attention.  I will check that out on Monday.  We have a national company here called Canadian Bearing.  I did check there for some of the other parts but Toro oddly enough was no more money.  I'm sure the shaft will be a lot cheaper though.  It might even be cheaper to have one done at a machine shop. There are only two key ways so it's just a matter of length I guess.  A full length keyway is no great deal is it?

 

I called my Toro dealer and the shaft was $179.00 plus we have 13% tax here and the pulley is another $57.00.  These things are not cheap to rebuild but on the other hand there isn't much left that can go wrong.  They never break until you need them. 

 

Can't push much more.

[squonk 41,051]

A fully keyed shaft would be fine. You could cut it to any length needed

[RMCIII 838]

Thanks Shorts and Mike.  That's something I'm not familiar with but glad you drew it to my attention.  I will check that out on Monday.  We have a national company here called Canadian Bearing.  I did check there for some of the other parts but Toro oddly enough was no more money.  I'm sure the shaft will be a lot cheaper though.  It might even be cheaper to have one done at a machine shop. There are only two key ways so it's just a matter of length I guess.  A full length keyway is no great deal is it?

 

I called my Toro dealer and the shaft was $179.00 plus we have 13% tax here and the pulley is another $57.00.  These things are not cheap to rebuild but on the other hand there isn't much left that can go wrong.  They never break until you need them. 

 

Can't push much more.

I'll take your price, of the shaft, any day of the week.... I had one priced for mine. $300.00 to the dealership.... Mark up is generally 20%. So, $360.00, just for the shaft.....

[Hydro 131]

Thanks again Mike.  I'm going to see what I can get other than a Toro part on Monday.  That should save quite a few $.  I will pull it apart tomorrow.

 

I have one other questions guys, what stops the shaft from turning inside the bearing?  They don't seem to need to be pressed on?? 

 

 

Wow RMCIII what blower/thrower model do you have?  Just curious.

[RMCIII 838]

It's for the "xi" line. I have a 518xi.

[shorts 182]

the bearings should have an eccentric collar that has a set screw on it, put the bearing and collar on the shaft and adjust for fit, then put the collar on the bearing and turn it on the eccentric to lock the bearing to the shaft and lock it doe with the set screw.

[Hydro 131]

Machining isn't something I know obviously.  Thanks Shorts that explains it as well as some other observations I wondered about.

[can whlvr 993]

hey gary,been away for a while but heres some info fo ya,go to princess auto,they sell the saft in 3 foot sections,about 35 bucks fully keyed,i just bought a 3/4 a week ago because I lost a bearing and it destroyed the shaft,you can get a better pulley there also,you just buy 2 pieces,a hub that will be 7/8 (I think that's your size)and a pulley,5 inch or what ever it is,i have one on my main thrower and its great,princess auto in barrie might have every thing nad you wont have to wait 2 weeks,ive also welded the pulley before,if the shaft and pulley are screwd then you have nothing to loose

[Hydro 131]

Thanks Don.  I will check this out.

[Hydro 131]

Well I went to Princess Auto today as Don recommended.  I believe this outlet would be similar to Northern Tool & Equipment.  So most everything comes from offshore.  I bought a 7/8" shaft with a keyway 36" long for $34.99.  The drive pulley with a centre hub which requires welding was $13.99 and a shaft bearing with collar was $7.49.  All together with taxes $63.81

 

Do I have the same quality? Probably not but will these parts do the job, my hope is they will.  Even if I have to replace bearings every couple of years I paid $69.00 for the Toro bearing for the other side of the shaft.  It's hard to believe there could be such a huge difference pricing.

 

Thank you Don.

Edited December 31, 2013 by Hydro

[squonk 41,051]

If you ever have to order from McMaster-Carr, at the most it's 2 days to your door.

[gwest_ca-(File Mod) 11,040]

Well I went to Princess Auto today as Don recommended.  I believe this outlet would be similar to Northern Tool & Equipment.  So most everything comes from offshore.  I bought a 7/8" shaft with a keyway 36" long for $34.99.  The drive pulley with a centre hub which requires welding was $13.99 and a shaft bearing with collar was $7.49.  All together with taxes $63.81

 

Do I have the same quality? Probably not but will these parts do the job, my hope is they will.  Even if I have to replace bearings every couple of years I paid $69.00 for the Toro bearing for the other side of the shaft.  It's hard to believe there could be such a huge difference pricing.

 

Thank you Don.

Check the OD of the bearing - it may be larger than the original. I also used the 4-bolt cast iron bearing holders which allowed me to move the shaft more to the rear for a larger driven pulley. I wanted to slow it down and it has worked well for six years. My original shaft was 3/4" and replaced with the 7/8".

 

Garry