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!

All of the things you described are common on those older blowers.
Yes the wheel bearing being worn can cause the gear problem.  Bearings are about $22.00.  You also need to check the bushings in the ends of the pinion sprocket gear.
They wear and also contribute to the gear mesh problem.  Check the teeth on the gear as well, they can become badly rounded.  If that is the case you'll have to replace it
You can find them on Ebay. 

The easiest way to do those repairs is to prop the tractor housing up on both sides after removing the bottom panel.
Pull the left wheel.  Drive out the pin in the lockout hub. Pull of the hub and then the axle half shaft.  Remove the bearing flange to get at the bearing.
Removing the gear is a little more involved and a lot greasier.  Find the master link and remove the chain.  Find the two drift pins on the shaft.  One is on the far right, the other is on the right side of the gear.  Make sure you use the correct size drift punch to remove the pins. Pay attention to the washer and their location.
Because of the grease fitting on the left end of the shaft you normally have to pull the shaft out the left side of the housing. Clean up the parts and check the bushing wear.
If there is any play, replace them now while you have things apart.  I just found out last week that Fastenal carries those flange bushing $2.50 ea.
The part is called a Nut Retainer Ariens part # 07002600.  You can order then from a bunch or different places. You might call around and see if you can find a place that has
an old tractor laying around.  They have been using that part forever.
The loose fit on the rod below is a repair that I just made on my blower.  What I did was to grind off the weld on the end of the rod. On the outside of the housing.
Once you grind off the weld flush with the tractor housing steel.  You can grab the rod with a vice grip and spin it loose in the hole.  Then pull it out one side.
Measure it, cut a new length rod slide it back in and weld the ends again. If you don't have a welder you would have to take it some place to have them do it.
I guess another way you could do it is to cut the rod longer and slide a shaft collar on each end.
I also welded on new ears on the blower housing.  The slots had been enlarged and were sloppy when on the rod.  I left the old ears on and made new pieces with slots
to weld onto the original ears.  Just make sure that you get them on exactly aligned or you'll do all that work and the housing won't fit on the rod. Or it will and you'll still
have play between the housing and the blower.
I'd also check the impeller bearing. While the blowers off.  If the impeller bearing looks like a normal bearing.  Where the outside of the outer race is flat.  Fastenal also
carries that bearing and it's only like $4.50.  A lot of the impeller bearings that Ariens uses have a curve on the outside of the outer race.  Those you have to get on ebay
or from a dealer. Unless that bearing is in really good shape I would replace it.
Those are good blowers I have worked on a lot of them and they are almost always worth repairing if you can do the work yourself.
 As long as the engine and auger gearbox are in good shape.  The pinion sprocket gear could cost you maybe 20,30,$40.00.

Looks like he summed up what I was trying to post last night when my internet decided to quit working.

In addition to the axle bearings, check the bushings on the sprocket that mates to the differential gear.  Those are part # 05502600 and needed to be replaced on mine.  The axle bearings aren't too bad to replace.  The whole axle needs to come out.  Remove the tire on the side with the differential lock, then use a pin punch to knock the pin out of the differential lock.  The pin might be tapered so if it doesn't go out one way turn it around and try to drive it the other way.  That will let you pull that side of the axle out.  Now you need to knock the pin out of the main axle from under the frame.  If you are taking it apart you might as well replace both axle bearings.  Might replace the bushings in the outer axle too if you are trying to tighten everything up.  Ariens is probably going to charge an arm and a leg for the bearings and you can probably get them cheaper from a bearing supply place.  Looks like part # 05417700 for the axle bearing.

I wouldn't worry too much about the play in the front end.  Just tighten it up and see how it works.  If you have a tap and die set you could just drill it out and put a bigger bolt in it.

Also pull the shear pins and make sure the rakes are not rusted to the shaft in the front.  If all is good grease them up and check the bushings on the ends and the impeller bearing in the back up there.

The good thing about the old Ariens is little changed over the years so a lot of parts can interchange.  Find yourself a couple old neglected blowers for dirt cheap and you will have lots of spare parts.

Guys,

Thank you very much for the help, I really appreciate it. I ordered some belts, a friction disk, 2 wheel/axle bearings, 2 of the bushings for the sprocket shaft, 2 of those Nut Retainers, some of the R3 auger gearbox grease, etc. The name and part number of those nut retainers was a big help, by the way, thanks!

I hope the new bearings will snug up the mesh between the two gears by enough to make them work properly again. I'd prefer to avoid replacing that sprocket if possible.

I was thinking about how to snug up the fit between that rod and the groove in the other half of the frame. I don't have the machine in front of me at the moment (traveling). But it seems like maybe I could mate the two halves of the frame securely, by standing it on the auger housing (wheels in the air). Then drill a hole through both frames, in one location on each side. Then put a bolt through both holes. Maybe use a shoulder bolt, so it will be held through the frames by a solid rod, rather than shearing sideways against the threads on the bolt. To remove the bolts, I'd need to remove the transmission cover, so that I could hold the nut that would be on the inside of the frame. But that's not a big deal, given how often I should have to split the frame. I don't have a welder, by the way.

I felt the impeller bearing the other day, it *seemed* OK, I did not notice any play in it. I need to look up what grease and oil are recommended for other items besides the gearbox. I need to change the engine oil, probably to 5W-30 Mobil 1, like I use in my current snowblower. And I may try lining the inside of the chute with plastic, as has been mentioned here. That seems like a pretty clever idea. I have to admit, the plastic chute on my MTD works very nicely, and nothing sticks to it. I may also try the Clarence impeller kit (haven't checked the impeller/housing gap on this one yet). But that's a very clever kit.

Got to do some more work on it tonight. Checked the auger gearbox oil level, using the test in the manual (raise the back 6", etc). It passed the test, has enough oil to wet the fill plug again. The augers each appear to be able to move on the auger shaft, and are not rusted in-place.

I removed both wheels and the axle. Drove out the roll pin by the right wheel. The bearings were quite worn, there is a lot of play in them. When I removed the left wheel, and went to remove the differential lock assembly, I found that the 1/4-20 grade 8 bolt, which holds it in place, had previously broken in half. I did not see any roll pins in that area that I had to remove. After sliding out the broken bolt, that differential knob assembly slid off. I have not tried to open it (have no need to).

I'm letting some PB Blaster sit on the nuts that hold the Bearing Retainers in place. I wish they had something besides flat-blade screwdriver heads on them. Very awkward to reach and hold. Now I'm waiting for the replacement bearings, etc, to ship.

Those flat head screws on the back of the bearing retainers "should" hold themselves in place.  They have little ribs on them that push into the frame similar to how wheel studs on an automobile are.  The auger bushings up front have the same type of screws on the inside.  That being said, a couple of mine were loose enough that a screwdriver was needed.

Sometimes people take of the locking hub loose the pin and put a bolt in it's place.  The pin for the hub is a solid pin.  Not a roll pin.  The bolt will work, but I would
go ahead and order a pin.  It holds the hub onto the shaft with a much snugger fit. 
Those small bolts can be a pain if they have lost their self holding power in the frame.  The good thing is once you get your new bearings installed those bolts won't
have to come out again for a long time.

Hmmm, OK. The screws that hold the bearing retainers might stay put. But I tried one last night, turned the nut, and the screw head turned as well. Tried to hold it with a screwdriver, tried again, and the screw turned again. Maybe the others will stay in-place, I don't know. If they all try and turn in the frame, is there a reason I couldn't replace them with hex heads, once they're out? At least I could hold those with a box end wrench.

On the note of the pin/bolt, maybe I didn't explain it well. I'm referring to a bolt that goes perpendicular to the axle shaft, and holds the Lockout Hub in place. It would keep it from sliding off the shaft when you go to pull the knob for locking/unlocking the differential. It's shown in the Parts Manual for 924082, as Item 42, in the Reduction Drive section, described as 1/4-20x2" cap screw, grade 8. I'm not referring to the spring-loaded pin that slips into the hub, to lock the differential.

I do see an Item 38, Bshg-Slv, listed on the drawing. I don't *recall* noticing something like that last night. Where does that bushing go? It's shown between the differential and the left-hand axle. Might it have stayed in with the bearing? I just want to make sure I'm not somehow missing a part. There is some wear on the axles where the bearings sit, unfortunately. I will try them as-is with the new bearings, since I don't want to go too crazy with just replacing everything. Thank you again for all the help.

Some models used bushings and some used bearings for the axles.  Most of the parts lists are for multiple models so they just show both parts.  That being said, there are 2 small bushings on the short side hub axle where the 2 pieces slide over each other.  These are pressed in pretty tight though as I had some trouble getting mine out to replace.  You probably could use hex bolts in place of the screws, however, I believe they will stick out too far on the side with the differential gear.  I think to remove one of my screws I had to hold the screw with the screwdriver at a 90 degree angle so instead of using the tip of the screwdriver I was actually using the side of it.

Keep in mind that mine is a 1977 model and probably a little different.

RedOctobyr wrote:  As was already stated, a regular bolt won't work because of the clearance issue with the diff.  You could try using allen cap head bolts.  They have a head that isn't as tall as
a hex head bolt.  What I have done in the past when I've had the issue with the heads spinning.  Was to remove the four bolts.  Clean the threads real well, make sure the
the nuts spin on without any effort.  Put the bolts back in and start tighten down the nuts.  Sometimes when they go back in the holes in a little different position.  They will grab in the holes once again just enough to allow the head to come in contact with the steel frame. And if you hold the heads with the screw driver.  They will tighten down fine without spinning the heads.

Sorry about the misinformation.  Yours is supposed to have a bolt holding the locking hub on the axle.  Mine which I guess is older uses a pin.

There are bushing inside both ends of the left hand short axle/housing. Slide it on the axle half way, (locking hub end first) and see if it's sloppy on the shaft. 
Then slide it on half way (correct end first) and see if it's sloppy on the shaft.  Hope that makes sense?

Tried the rest of the bearing flange screws. 3 came off (the screws stayed put, held into the frame). The other 5 just spun :) I managed to get one of them off, using a 90-degree screwdriver. The others will all probably be Dremeled off. If I can find maybe some button head socket cap screws, or possibly low head socket cap screws, I might try to install those as replacements. At least I could hold the screws with an Allen wrench, vs a screwdriver :) If the threads weren't so rusted up, they probably would have come off OK. Removed one axle bearing, it is a sloppy, worn-out mess.

I looked a bit at bushings on the axle. The outside end of the left axle is snug, when I install it backwards. It also felt OK when installed normally. I didn't dig around in the grease on the inside of the left axle, trying to see if I could find a hidden bushing buried in there :)

I have to say, the grease fittings seem to be a big help. Much of what I've tried to remove, if it's not exposed threads, has been lubricated, and came off OK. This may be my only piece of OPE with grease fittings (my Craftsman tractor might have a one or two); it's a nice feature. I'm hoping to find some good, suitable grease, which won't get too solid/sticky at low temperatures. I've seen marine and snowmobile greases mentioned. I found marine grease at Lowes. Not sure where to find snowmobile grease, or something else that's meant for low temperatures. I've used wheel bearing grease on my MTD (it's what I had), on the shaft that the friction disk slides on. That must be too sticky, because the shifter lever is quite stiff on that one, by comparison, and the grease feels tacky on the shaft.

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.

Success. Shryp, your post got me thinking about grabbing some sockets. I got a set of Craftsman Evolv allen sockets ($10, vs $30 for the "normal" Craftsman set). The Evolv line is apparently made in China. Still has a lifetime warranty, but I did note that the package says your need your proof of purchase for the warranty (the regular Craftsman stuff does not specify that). The salesman said they're not insisting on that yet, but they might in the future.

Anyways, got those home, and figured I'd go for broke, so grabbed my Harbor Freight electric impact gun (240 ft-lbs max). It did in about 1 second what I couldn't do in 3 days of soaking and twisting by hand, the setscrew came flying out :) That impact wrench is becoming awfully handy.

The holes had some rust in the threads right where the setscrew threads meet the shaft. You couldn't thread the screws in any further then they had been, they'd just bind up against the rust. So I gently ran a tap down each one to clean them up, then the new screws I bought went in fine.

Coated the shaft, the woodruff key, and the inside of the hub with snowmobile grease, heavily anti-seized the new setscrews, put a dab of grease in the screw's heads (to prevent rust), and reassembled it. Bolted the machine together before tightening the setscrews, so I could align the impeller pulley with the pulley on the crankshaft. I didn't use a torque wrench on the setscrews, since I didn't see a torque spec in the manual.

Adjusted the drive tension, checked the impeller belt tension. Took it outside, the transmission seems to work well, and the augers turn fine :) Next up, an oil change, maybe install the new friction disk I'd bought, and add a fuel filter. I do want to address the slop between the worn bar and the frame, where the two halves split, down at the bottom. And there is a lot of rust, sadly. I may try one of the rust treatment/protector products for this winter. Painting it seems like a big undertaking. I wonder if Ariens makes touch-up paint that you can brush on, for addressing little areas without having to mask things nearby.

That's great that you got the other allen screw out.  I've got one of those 18V impact drivers and they work great for getting out really stuck and frozen bolts.
Here is a photo of the rod repair I made on my blower.   That rod is held in place by a weld on each end, on the outside on the tractor housing.  If you simply grind down the weld so that
the steel at that point is perfectly flat.  And then grab the rod with a pair of vice grips and turn it.  It will break free and you can pull it out of the holes on either side of the housing. 
If you don't have a welder to weld it back in place.  You can use shaft collars on both ends to hold the new one in place.  Get a piece of 3/8 rod and cut it long enough so that there is enough
rod sticking out on both sides of the housing to slide on a shaft collar..  Also measure of the width of the housing where the rod is before removing it.  It needs to be exactly the same width
after you have installed the new rod.  The belt keeper behind it should keep the housing at the correct width but it's better to know what the measuremnent should be.

RedOctobyr wrote:
I did some spot painting of the chute and auger housing with great results, with a spray can.  Granted, I completely disassembled the attachment, but I think some wet sanding with 2000 grit will take care of overspray.  I sanded and primed and then used Chevy Orange Engine Enamel.  Though it matches quite well, I wonder if Hemi Orange isn't a better match.

http://rustoleum.com/CBGProduct.asp?pid=372