JD 47" snowblower gearbox question

[mikefamig]

I am new here at tractorbynet and a new John Deere owner so bear with me. I've been searching out info here for a week or so and hope that you guys can help me with a problem.

I just bought a slightly used -180 hour - X728 tractor with a bunch of accessories and I',m in the process of rebuilding a model 47 snowblower. I have it stripped down to the bare metal enclosure and plan to replace the 5 bearings and chain but I have a question concerning the gearbox.

The thing is that there is quite a bit of backlash in the auger. When I look at it closely I can see that the gear hub that holds the auger shaft is pretty tightly connected to the input shaft with little backlash leading me to believe that the ring and pinion gears are not very badly worn. but there is considerable play between that hub and the auger shaft.

My question: What holds the hub to the auger shaft? The shaft slips easily left and right in the gearbox pretty freely. Can I slide the shaft from the gearbox without disturbing parts inside the gearbox? Do I need to open the gearbox to deal with this looseness?

Anyone?

Thank you in advance, Mike.

 

[KennedyDiesel]

The auger shaft is greased and I'm pretty sure that they engineered some "slop" into the shear bolts so that they move to keep lubricated.

 

[mikefamig]

What I am talking about does not involve the auger or the shear bolts. I'm talking about play between the auger shaft (31) and collar (26) in the diagram below.

 

[mikefamig]

Well I removed the auger shaft from the gearbox this morning and answered my own question. After removing the augers the shaft just slides out of the gearbox freely. JD used a woodruff key to to make the shaft rotate with the output gear/sleeve in the gearbox. My woodruff was beat up and it looks like a new one will fix it up.

Maybe this info will help someone else out there.

Mike.

 

[Henri88]

But 26 is the auger shaft and 31 is the auger sliding over that shaft and is usually secure with a shear bolt at both end of the augers, same system as # 3. Your 47" blower could be an older model then the one I have with a different set-up. What year is it do you know. Pics would also help. Henri

 

[Henri88]

Ok, I was writing this as you post yours. Happy you figure it out. Henri

 

[mikefamig]

No 26 is a collar that is pressed into the wedge gear and is inside the gearbox. 31 is the shaft that engages the collar. Both the collar and shaft are slotted and engage each other using a 1/4" key. What I have been calling the "augers" are the big flights that move the snow and ride on the auger shaft.

Mike.

 

[mikefamig]

Which leads to my next question......how much play is there in this connection on a new machine. Is it snug or did JD leave some play? The slot in the shaft looks to be in great condition but a new key does not snug it up completely, there is still some play.

Mike.

 

[Henri88]

Got it, but my question stand, what year is your blower. The diagram that you posted looks different than the set-up of my blower. Henri

 

[mikefamig]

Got it, but my question stand, what year is your blower. The diagram that you posted looks different than the set-up of my blower. Henri

I'm sorry but I'm not sure of the age of the tool. I bought it used and it is supposed to be about 5 years old. It has the steel thrower as opposed to the newer carbon fiber part and is identical to the diagram that I posted above.

Mike.

 

[mikefamig]

Henri:

Is your blower a model 47?

 

[Henri88]

I took a run and measure the free play in my auger. It's about 3/4" taken from the highest point of the auger. Hope this help a little. Took a few pictures of mine but if like you said 5 year old it would be the same.

 

[mikefamig]

I took a run and measure the free play in my auger. It's about 3/4" taken from the highest point of the auger. Hope this help a little. Took a few pictures of mine but if like you said 5 year old it would be the same.

View attachment 308290 View attachment 308291 View attachment 308292

Yes that looks just like my machine but mine had more like an inch and a half of play so thank you that does help. I cleaned up the parts and took a close look at things and the slot in the shaft is badly beat up while the gearbox looks good so I'm a happy camper.

Now I am looking for a good way to repair the key slot in the shaft. I am considering using some silver solder in the slot and then filing it to fit. It will be tough because the shaft needs to slide smoothly in the gearbox when assembled. At worse I will need to get a new shaft which is a site cheaper than a new gearbox.

 

[Lcagee]

I get confused by all the terminology here. Gearbox. Auger. Shaft. Woodruff key. There seem to be two gearboxes. One in the rear. One in the front. Also there are two Deere 47 snowblowers. One with the black chute, one with the yellow. I don’t know which one is old and which one is new. Anyway, I have a 47 black chute. The rear gearbox is broken. I’m trying to remove it. I removed all the screws but there is something preventing me from pulling it backwards to remove the shaft that goes into the rotating thingy. How do I get it out? Do I need to remove the other rotating thingy?

 

[beenthere]

Post some pics of the blower and especially the s/n tag.. we'll see if we can help you sort this out.

Welcome to TBN

 

[al3]

The gentleman that started the below post had the older model blower and wound up making a part for it. Lots of good pics of that particular model, illustrations, parts schematics and actual photos. Might help you determine which one you have.

Repairing sheared impeller shaft - JD 47 snowblower attachment

I have a good friend with the older model 47 snow blower attachment that runs on his 430 tractor. Unfortunately, the shaft that carries the impeller sheared off. And worse yet, JD only sells the entire gearbox for around $1400, not the individual components. After disassembly, this appears...

www.tractorbynet.com

 

[Jims1025R]

I'm well into work on my JD blower also - 58" front mount, converting to a three point rear mount. Avoid "front" and "rear" to describe the gearboxes, it could be confusing. One gearbox changes speed, PTO to fan speed, and will be bolted to the tractor side of the blower box. The other is a right angle drive, from the continuation of the fan drive, to the auger shaft.

I suggest that evaluate taking the whole auger assembly out, it shouldn't be that much work. Unbolt the auger shaft ends on the inside of the box ends, and the piece which suspends the right angle (Auger) gearbox from the box ceiling, and the whole thing should pull forward and out. There should be a spline shaft joint, which just slides apart from a universal joint in front of the fan. A spray of penetrating oil never hurts.

With that out, you'll have full access to the fan side. Yes, there will likely be a key between the fan hub, and the shaft from the PTO gearbox (on the tractor side of the box). That key may be held in place by a "grub" screw (allen key down a hole in the middle, no head). Again, spray of penetrating oil, and maybe warm up with a heat gun. Clean out the allen key hole, so the allen key will go well in. Don't ream out the allen key hole in the grub screw, the scope of the task will grow immensely!

With the grub screw out, the fan and hub should slide off the PTO gearbox shaft, and you'll see the key in there. Then you can remove the gearbox from the tractor side of the box.

All that said, for the work involved, I'd assure that you can get the needed replacement parts before you invest the effort. As said above, some parts are hard to get. The PTO gearbox may be rebuildable, though it'll be a machine shop type job.

With the PTO gearbox off, is anything (a shaft) obviously damaged/broken? Does it spin freely? If nothing seems wrong, before considering disassembly, remove the oil filler/drain plugs. Pour the oil out through a find sieve. Of no metal is in the oil which comes out and it spins freely, I'd refill the oil, and not take it apart at all.

If you get the PTO gearbox off, and need to take it apart, do it over a pail, it should be partly full of oil. At least two of the PTO gearbox bolts should be "shoulder bolts" (maybe allen head, not hex head). These serve to both hold the gearbox together, and to hold the two halves in perfect alignment. They may be a tight fit (that's the idea). If you have to tap them out, thread a sacrificial nut partly on, and hammer on the nut to get it started, don't hammer on the end of the male threads, you'd regret it later! If the two gearbox halves are stuck together, a sharp blow with a plastic mallet, or light tap with a hammer, on the side of the gearbox, not near a bolt hole should help - "pop" and oil comes out! Reassembly of the gearbox requires some special techniques, so don't get yourself there unless you really need to!