# 924 Cast Iron Gearbox Seal Replacement



## chilly (Oct 11, 2018)

My 924126 had a leaking gearbox (from the auger shaft seals). So I replaced them. It's a bit of a pain in the butt, so here's how it went for me.

Basic stuff is to get the auger assembly out of the snow blower. Augers, gearbox and impellers. If getting those off the machine was a challenge for you, I'd take it somewhere to get the seals done.

You need to crack open the gearbox, and unfortunately, pull the impeller seal and bearing to release the worm gear and remove the pinion gear to remove the seals.

Pain #1 is gettng the 'adjustment plug' of the impeller shaft/bearing out.
Pain #2 is getting the impeller outboard bearing cone out.
Pain #3 is getting the impeller outboard bearing cone back in .

With a nice big bench vice and a proper spanner/pin/hook wrench, #1 is easier, but #2/#3 would still be tough.


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## chilly (Oct 11, 2018)

You have to get the gearbox apart and get the mini-shaft and pinion gear out. To do this, you have to get the main impeller shaft loose. Getting this notched/slotted adjustment nut out was one of the worst parts. You might be able to hold the gearbox in a vice and hit it with a chisel/drift, but it never 'loosens'... It doesn't take a huge breaker bar to break loose, but it's a consistently firm turn the whole way out. Would be a major hassle knocking it out a 1/16 of a turn at a time with a chisel.

If you had the right spanner/pin/hook wrench to do it, it wouldn't be that bad. You'd have to hold the gearbox in a vice, or stick the main auger shaft through it to hold for leverage against turning that bit out (that's what I did without a good vice to use).

I got super lucky and found a piece of a gear puller that just happened to fit in the slots in that adjustment nut.. and with the help of a monkey wrench and the main auger shaft to leverage against, I got that nasty mother out.


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## chilly (Oct 11, 2018)

Hassle #2 is getting the impeller conical bearing race out (to release the shaft).

I held the impeller (still mounted to the shaft) and whacked on the crank case with a rubber mallet until it finally backed out. it is not a nice light slip fit. It's not a 10,000lb press either... and it did come out with some work. If you could rig up a way to press the parts (impeller and gearbox) apart it might be easier. The leftmost 2 pieces in that pic are the 'bearing adjustment' nut (that has the shaft seal inside it) and then the conical bearing race that was pressed into the crank case.


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## chilly (Oct 11, 2018)

I don't 'think' the pinion gear is directional, but to be safe, I scored mine with a dental pick on one side so I put it back together the same way it was.


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## chilly (Oct 11, 2018)

I have a seal puller from doing my trailer seals. These were pretty easy in comparison. I didn't need to hammer/mallet anything and they pulled out with a bit of hand pushing force. I had to remount the left side plate to hold things in place to pull the seal from that side.


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## chilly (Oct 11, 2018)

Pressing in the new seals wasn't too hard. They were all rubber with the spring insert (no metal seal body). I used a really big socket to help drive them in evenly, but honestly, not a tight fit and probably would be fine with just a rubber mallet.


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## chilly (Oct 11, 2018)

My pinion gear 'mini shaft' was lightly scored and since that's the leak I was trying to fix, I wet sanded that surface with 400 then 600. It wasn't terrible, but wasn't perfect.. but I didn't want to get too aggressive with the grit. Turned out pretty darn smooth.


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## chilly (Oct 11, 2018)

2 main hiccups getting things back together:

#1: Putting pinion gear shaft back in through the seals. it's kind of opposite the direction you'd like. It feels like it catches on the lip of the seal and you don't want to just shove it. Maybe my assembly order was wrong, but I don't know how you'd do it otherwise. Anyway, I just lightly pressed it up against the seal as I inserted it, and lightly ran my fingernails around the edge of the shaft and got the seal to slip over, being careful not to force things and damage the seal. It wasn't too tough. Grease helps.

#2: This is the biggest hassle of all. To get the spanner nut / bearing adjustment nut started in it's threads, you have to knock the conical impeller shaft bearing race in a fair bit first. it doesn't just drop in, so have fun! I found a small 1/4" mini socket extension that I was able to use to help me tap it in with a mallet/hammer a bit manually, before I was able to get the spanner nut on. Be careful not to damage the impeller shaft surface either, or it may cause leak with it's seal later. Once started, I used my gear puller hack from shown earlier, I was able to tighten down that cone bearing race so everything was tight and moving smoothly.

Honestly, I found it to be a really a huge pain, but it doesn't leak and only cost me $12 for both sides. If I was a mechanic with every tool in the book and a nice shop, it wouldn't be as bad, but still a bit of a hassle.


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## JLawrence08648 (Jan 15, 2017)

Is this a PIA for all Ariens? Most? Same PIA for many or most makes?


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## chilly (Oct 11, 2018)

JLawrence08648 said:


> Is this a PIA for all Ariens? Most? Same PIA for many or most makes?


I couldn't say - but if they have that same mechanism with a slotted adjustment nut around the impeller shaft, and a press fit conical bearing race behind it, then probably yes.


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## Bob from Duanesburg (Dec 27, 2020)

Thanks for your posts on this. I am working on a very similar issue. In my case one of the bearings went and the drive shaft booger-ed up the adjustment plug. It was a major PIA to get this thing apart. In looking at the parts diagram I see a snap ring on the end near the dust cap. Do you think it is possible that the dust cap should be taken off, the retaining snap ring out and all the inner parts (bearing, gear, spacers, etc.) left in the gear case, not taken out with the shaft? To assemble, insert the bear shaft with all the inner pieces in the gear case, not on the shaft, making #2 and #3 easier?


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