Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Hi all,

I just bought a 1993 (I think?) Ariens ST824. Model 924082, serial 0040XX.

The good news: Paid $150, the augers weren't turning (the belt had come off, and seems like it needs to be replaced). It starts & runs fine, and has electric start. The engine showed ~120-130 psi when cranking it with the electric starter, and ~60 psi when pulling it by hand (I don't know whether those are good or bad). It has a differential, rather than the simple pin-through-the-axle setup of my MTD. I thought that was a cool surprise, I didn't expect a differential. Is that common on the ST824's, or did I get lucky? The differential works fine. It's a weird feeling being able to just steer it.  I get the impression that the previous owner gave it some grease occasionally, since the gearbox area seems well lubricated. The person I bought it from just got it recently, so I don't know its history.

The less-good news: It has a fair bit of rust, unfortunately (may have been stored outside?). But it seems solid. There are two areas that concern me so far.

One is that the big gear on the differential can skip against the teeth of the mating sprocket. There appears to be quite a bit of play in the wheel bearing on that side (the bearing at the other end of the shaft, for the right wheel, seems a bit better). So I think the shaft is being allowed to move too far away from the mating sprocket, and it's able to skip. Is this common? It looks to me like replacing the wheel bearing should do quite a bit to help make the gears tight again. Am I right? Is that a difficult job? Special tools needed, etc? It sounds like a tapered roll pin has to come out, from glancing at the service manual. 

The other issue is that there is play between the two halves of the unit. The tractor half, and the snowblower half. The big bolts at the top of the frame, which join the two, were loose, and able to bang back & forth. It seems that it's been used like that for a while now, unfortunately. One of those bolts can't be tightened, the nut (below the frame) just spins. I'm having a hard time figuring out a part number for that nut. As a result of those bolts being loose, I assume, the bottom area, where the two halves join, has also worn. There is a rod in the tractor half which slips into a groove in the snow blower half. That groove has opened (I think) and the rod has worn smaller. So there is play down there as well. I'm not sure if there's a good way to try and take up that play, with some kind of bushing perhaps.

So I think I need at least some belts, a friction disk, probably one wheel bearing (I'd prefer to leave the right-side one alone, if possible), and I'm sure some other random parts. Maybe I can figure out some way to tighten up that rod-to-groove fit at the bottom.

Does this sound like it's worth fixing up? I'm looking for something reliable and durable to replace my MTD 8 hp, 26". I just don't know whether the issues described above should really never happen, and therefore this machine has been put through a LOT. And that maybe I should look for a different one. I don't have a problem fixing this stuff, as long as a handy homeowner can replace the bearing, and so on. I just don't want to start down a rabbit hole.

Thank you for any feedback or suggestions!

RedOctobyr wrote:
Yea those little bolts for the bearing flanges can be a pain.  And your right, it's the rust that messes things up  I know Ace Hardware carries allen cap bolts. I've bought them there before. I wouldn't even be surprised if
you could find replacement bolts as well.  Ace Hardware has an amazing assortment of specialty nuts, bolts and small hardware.  The best I've ever run across.

A black moly grease works pretty well for the axles.  On the shaft for the friction disk slide, I guess you talking about the hex shaped one?.
 I always spray some carb cleaner on a rag and clean off the shaft real well.  Doing that alone will make the thing slide easily.  Just a light coat of white litium or even the
moly grease will work.  Your right, axle grease is too thick and sticky.  Just don't put much on it, just a light coat.  The shaft spins pretty fast and if the lube slings off it can get on the friction drive disk.  Not good.  Your going to have a nice blower when your finished.  All the parts your replacing are probably original.  So they lasted what 20+ years.  That's pretty good.

Just wanted to post an update on how this is progressing.

I cut off the remaining screws for the axle bearing retainers. Replaced them with stainless flanged button head cap screws, which have the same head height as the stock screws. So they should not interfere with the differential. You *need* to hold the heads now when tightening/loosening them, but at least an Allen wrench works nicely. Once the stock rusty ones spun in the frame, I couldn't do much to hold them still even with a 90 degree screwdriver. I did use a hex head bolt on one of the right-hand ones, since I couldn't fit an allen wrench between the auger pulley and the screw head.

Replaced the axle bearings, which were completely toast. Unfortunately, they had started to move relative to the axle shaft, and wore the shafts down from ~1.125" to more like 1.100". For the time being, I wrapped some stainless shim stock around the shafts, underneath the bearings, to try and take up some of the slop. If the machine proves its worth this winter, maybe I'll try a more permanent fix in the spring. The most permanent solution would be to weld up the areas of the shafts, then turn them back down to size. Replacing them would also work, but they're expensive :)

Also replaced the bearing for the hex shaft that the friction disk rides on. That was also worn out. I bought the bushings to replace them for the pinion shaft (the one that the mating gear for the differential rides on). But in trying to tap that shaft out of the frame, it was getting tight. I'd removed the roll pin at the right-hand side, but I was concerned that if I got the shaft out, I'd never get it back in without disassembling a bunch more stuff. And the bushings are in OK shape, so I left them for now.

Adjusted the Reduction Shaft's location to snug up the tension on both chains. Managed to find some snowmobile grease, so greased all the fittings in the transmission with that. Apologies for not using the black moly grease you suggested, jrtrebor; reading up on grease suggestions here showed a number of people suggesting marine or snowmobile grease. The snowmobile grease seemed like it ought to stay useful at cold temps, so I used that.

The new axle bearings appear to have helped tighten up the mesh between the differential and the sprocket. So that's good. I'll find out more when I can do some more testing.

Also replaced the auger belt, and tried the augers. After 5-10 seconds of running at low speed, I started seeing smoke. Immediately shut everything off, and found that the auger pulley is loose on the shaft, and had slid towards the engine/tractor half, and was rubbing against the differential. Split the halves tonight, and the auger pulley and hub slipped right off the shaft. The woodruff key is intact. The two allen setscrews in the hub are stuck at the moment, so have them soaking with PB Blaster. Is it typically the hub that people have said is difficult to remove from the shaft? I think so, but maybe I'm wrong. If so, I guess I don't have that problem, at least :) There is some play between the auger shaft and the auger bearing, but I'm planning to leave that alone for the moment. Replaced the big Nut Retainers, which were both broken. Thanks for that part number, jrtrebor.

I know it's a whole other discussion to itself, but any suggestions on something to help protect the rusted & exposed areas for this winter? If I try any repainting, it will likely be in the spring. Thank you again for all your help.

Sounds like your coming along.  You will have a good blower when your through.  As far as the rust goes for this season.  I would just remove any loose stuff.  Wire brush, wire wheel on a drill.
Whatever works.  Dust off the areas, wipe them down.  Carb spray on a rag works well.  Coat the areas with a rust stopper spray.  Auto stores have it and I believe home depot.  Comes in a spray can.
Goes on clear then turns black where ever there is rust.  Then hit those spots again with a red oxide primer that's the brown stuff.   Rust-Oleum is what I normally use. Your then good for the winter.   I may not be as pretty as you like but it will keep the rust at bay until next spring.
That's about the best you can do.  

RedOctobyr wrote:
I have the same model and roughly the same vintage, perhaps a year or two newer.  I've been working on the attachment more than the tractor.  My tractor is in great shape. 

I believe your reference to the auger pulley and bearing, you actually mean the impeller pulley and bearing.  I was able to get this off using a harmonic balancer pulley puller from Autozone's tool loaner program.  You can search for "924082 impeller bearing removal" or similar on this site to see the specifics.  Send me a message if you need more info.

I was going to pull the impeller off but was advised against it.  Right now I'm working on sanding and painting the bucket inside and the black parts like the impeller and auger.

Good advice, jrtrebor, I may try that. manjestic, that's kind of the funny part. The impeller pulley (sorry, yes, that's what I should have called it) was already loose on the impeller shaft. This is the shaft that goes forward to the auger gearbox. Once I split the machine, the impeller pulley & hub simply slipped right off the shaft. The only thing holding it there was the woodruff key, keeping it from spinning on the shaft. I hit the rusted allen-head setscrews with PB Blaster, they hadn't loosened up yet this morning. So I tried the 50/50 acetone/automatic transmission fluid suggestion I read about recently, as a different penetrating oil. I'll try them again later and see if I can get them to loosen up. Before reassembling the hub and pulley onto the shaft, I am going to coat the shaft and hub with either antiseize or grease. I presume I should use Loctite on the 2 setscrews in the hub, when reassembling it.  

RedOctobyr wrote:
I use antiseize on just about everything, great stuff.  I don't think I would use any Loctite.  A combination of Loctite and rust would make those bolts impossible to get out again.
 If you get them tight they shouldn't loosen up.  I've never had any come loose.
Run the screws/bolts in and out a few times to loosen up any rust that may still be in the treads.
Then clean the threads on the screws/bolts and in the hub.  Just shoot both with some carb cleaner.  That way when you tighten them down again. There wont' be any binding resistance.
That can give a false sense of how tight a bolt is.  You'll feel that when you taking them out. They will likely be tight all the way out even though they are broken loose.

If you haven't tried again already.  Make sure that the allen hole is clean so that the wrench can get as far down in the hole as possible.  Sometimes I will use the side of a small hammer to hit
 the allen wrench.  That jarring blow sometimes helps in breaking them loose.  I've also slipped a short length of tube over the allen wrench to give more leverage.  I only do it that way if I've had
 to take the pulley off the hub.  Usually I use an allen socket on an extension with a ratchet.  Last week I had two of those allen bolts that were simply not going to break loose.
So out came cutting wheel.  That's never fun.  But those hubs are so brittle, that once you make one cut.  You can crack the rest of the hub off in pieces with a chisel.
Hope you have success.

My set screws had traces of blue Loctite. I'm thinking they came like this from the factory. I know the previous owner and i'm fairly certain he did not remove them or apply Loctite.

Well, after some soaking, I got one of the Allen screws to break free. The other one is still quite stuck. I've tried giving the screw head a few whacks with a hammer, put on more penetrating oil, etc, and have managed to put a nice twist in 2 of my Allen wrenches :) I don't have a socket-style Allen wrench, unfortunately. I tried heating it with a soldering iron, that didn't do much. If I can find my torch (figures it's AWOL at the moment), I may try that, in case there is Loctite which needs to be softened. For what it's worth, manjestic, the screw I got out did not have any visible Loctite on it. Worst case, I could leave this screw in-place, and drill & tap a hole for a new screw, on the other side of the hub. But I would rather get this one out, if possible. Fortunately, the hub has already come off the shaft, so at least I have good access to it.

I picked up a set of these somewhat recently from harbor freight

http://www.harborfreight.com/hand-tools/sockets-ratchets/9-piece-38-and-12-drive-sae-hex-bit-socket-set-67884.html

Not too expensive and very useful.  (The holder they come on is a different matter)

Correction: The day after I posted this I snapped the 5/32" one off...

Seeing as how the hub is off the shaft.  You might consider just drilling out the remaining frozen set screw.  Starting with a bit that's just a little smaller than the allen hole will give you a nice straight
pilot hole.  Then find a bit size that will drop in the the empty hole that you have.  Use that and if you keep it nice and straight.  You may be able to use the old hole and threads.  Just run a tap thru
the hole after you drill it the second time.  Just a thought.