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I have been meaning to remove and open up the transmission for some maintenance, but the process of removing it seemed to be somewhat complicated. Today, I decided what the heck . . . gave it a shot.

I found a set of transmission removal instructions on the Internet, so that was helpful.

Here is the process with a few of my tweaks and some pictures, for anyone who may need it.

1) Drain the gas (unless the tank is fairly empty)

2) remove the top belt cover pull it to the right side

3) tip the machine up on the bucket

4) disconnect the shift linkage at the ball joint near the transmission & remove the chassis back plate that covers the transmission

5) rotate the wheels to move the chain until you see the master link & remove the master link & the chain

6) remove the wheels

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7) remove the 2 large shoulder bolts that form the pivot of the powershift & remove the axle assembly

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8) remove the lower belt cover

9) remove the retainer for the cable that leads through the chassis on the right side & slide out the barrel end of the cable to make it loose

IMG_1145.JPG

10) remove the pivot latch assembly by removing the bolt on both sides and detach the cable that controls the pivot latch by removing the retaining plug, be sure to account for the spring that provides downward tension on the pivot latch upon re-assembly.

11) remove 2 bolts on both sides of the transmission mount that hold it to the chassis

12) push the transmission up & remove the belt

13) pull the transmission mount out and turn it so that you can access the top bolts holding the transmission to the mount.

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14) remove the 4 bolts that hold the transmission to the mount

15) remove the forward/reverse cable from the transmission by loosening the retaining bracket

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I got the transmission on the bench for disassembly. There are a couple of roll pins that have to come out before you separate the case halves.

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The gears and linkages looked pretty good as there was a fair amount of grease in the transmission case.

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I don't think I'll need to do too much work on it, since there is no internal rust on the gears, etc. The whole disassembly of the machine seems like a lot of work, just to get a glimpse inside the tranny, but probably something that is only needed about every 10 years or so.
 

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clean it up, pack with new white lithium grease, and put back together........if any rust, wire brush on wheel every gear and shaft....then put back together.
 

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Discussion Starter #5
Yes, I've seen the YouTube series that @Sblg43 has on the tranny rebuild. My issue was understanding how to get the tranny out of the machine to begin with. Flipping the machine up on its bucket was the key to success.
 

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Wow, that is quite a process. Nice job getting it out and apart!

After working on my lawn tractor's transmission this fall, that type of transmission setup is now more familiar. My tractor transmission wore out its differential gears, and began slipping. It ended up being cheaper (and easier) to buy a used replacement tranny locally, rather than to buy the ~6 individual differential components.

It probably has no "bearing" on things, but the worn-out tranny had grease in it. The replacement had gone to gear oil. The grease had pretty much all been pushed away, as shown in yours, so it was piled up next to the gears. The gear oil at least *seems* like a good choice to me, as the gears sit in the oil, and distribute it whenever the tranny is spinning. There was a lot of grease in my worn-out tranny, but most of it was next to the moving parts, and no longer on the gear teeth. I'm hoping the oil-holding replacement will hold up better.

At least you can redistribute some of your grease onto the gears. I've heard not to mix different greases, as some are incompatible, and will not lubricate well if mixed. So it might be good to get the old stuff out, if you're going to add something different.
 

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Discussion Starter #7
I was thinking of going with oil to keep the lubrication up. Any reason I should not just add oil to the the grease in the gear case?

Since there is no rust, I don't plan on taking the gears out.
 

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Adding some gear oil to the case is kind of what I was thinking. Maybe that's a bad idea, but it seems reasonable to me.

You don't want to flood it and have it dripping everywhere. But adding some oil, enough to have the larger gears dipping into it, seems like it might be useful. It might get tossed around enough to help keep a coating on things. But not so much that it will overflow out the holes where the shafts exit, since I'm guessing they don't have seals for this.

I'm curious what people with experience with these say, however.

I don't have access to a parts washer at the moment, which seemed like the proper tool for cleaning old grease off the gears, casings, etc. So I was kind of glad I didn't have to try and decide whether to replace the grease in my old transmission. So far, I prefer the idea of oil in the replacement tranny.
 

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I added the link to the videos since someone coming here later on looking for info would likely benefit from finding out how to remove the trans and tear into it. I know I have. Will bookmark for this summer hopefully I'll have a chance to work on one of mine.

I haven't looked in a service manual for it but I would think 00 grease would be the thing to use. It's what they use in lawn mower and lawn tractor transmissions. It's thinner than grease but thicker than oil. That's why it works well in cold temps and doesn't get past a good seal.

.
 

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Discussion Starter #10
I poured some Quicksilver gear oil that I have for my boat engines into the lower case of the transmission. Just enough to have the gears dipping in the oil as they turn. I'm thinking the combination of the oil and grease will make a slurry of lubrication.

As I work on this Toro Powershift, I am thinking it may have gone in for major maintenance about half-way through its 19 year life.
 

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Discussion Starter #11
I buttoned up the transmission and cleaned up the casing. I put a bead of flange sealant around the casing half before closing it up, just to make sure it had a good seal and would not seep any oil, etc.

IMG_1154.JPG

then I went to install the transmission using the reverse of the 15 step process. Tightening the bolt on the reverse cable bracket . . . and . . . ooooppps. the bolt went in and before I could even put the slightest amount of torque on it the thing spun freely. :surprise: . . . the threads were stripped :sad2:

IMG_1158.JPG

Not sure at this point if I should go with a helix coil or just tap the next larger screw as a fix. :icon-shrug: thoughts?

In other news, I was cleaning up the wheels and decided to take the tires off to clean up the rims. I managed to puncture the inner tube on one of the tires. It seems like I don't have the proper tool to remove the tire. I got a full-size tire changer tool, but not something that is small enough for OPE tires/wheels.

Any help with the tire changing? Do I need the inner tubes, or will the bead hold air like on an automotive tire?

For now, I'm going to limit myself to re-painting some of the chassis frame parts, hoping not to do any more harm. :plain:
 

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Ugh, that sucks about the stripped screw, sorry.

I can't tell from the pic, does it go into a boss raised up from the rest of the tranny case? Or is it flush with the top of the case?

If it's good with the case, then hopefully there's a decent amount of metal around the tapped hole.

Can the mating piece accommodate a larger diameter screw? If it can't take a larger screw, then you'd have to use a Helicoil. If you can use a bigger screw, then I'd figure out which method requires a smaller hole. I suspect that a Helicoil would require a larger hole, increasing the risk of breaking through the side of the boss in the tranny case, when drilling and tapping.

I was under the impression that most of these blower tires are tubeless. But if this has tubes, then maybe it requires them, either due to wheel/tire design, or possibly leaky tires at some point in its history. I don't know, sorry.

I've heard people say that removing/reinstalling the tires on these can be a real bear. Even with the small Harbor Freight tire changer.
 

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Discussion Starter #13
The screw abutment is slightly raised from the surface of the case, but also sunken into the case for thread depth. I think it is a 3/4" long bolt, 1/4" - 20 thread size. I checked the bracket and it will not take a 5/16" bolt without a reaming. So, I think I'll go the helix route.

As far as the tire, maybe I can patch the tube, otherwise it is off to Tractor Supply to get another one. I assume that the tube was there for a reason.

I guess this is one of the reasons to have more than one snowblower, because if you go to work on it an stuff happens to delay the process, you've got a back-up or two :plain:
 

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The tap drill size is a little smaller for a 5/16"-18 thread (0.257"), vs a Helicoil for 1/4"-20 (0.266"). So, if it was easy to drill out the hole in the bracket to accommodate a 5/16" bolt, then going to a 5/16" would leave just a little bit more material in the tranny casing, vs using a Helicoil.

Also, on sealing the transmission halves. For my tractor, I used a "Hylomar"-style sealant by Permatex. It was recommended because it's thick enough to help form a seal, but it doesn't harden. So, unlike silicone, for instance, you aren't gluing the tranny halves together, which can make them kind of a bear to disassemble in the future.

It worked out well, because sure enough my first fix didn't work, and I had to open the case a second time. Fortunately, it split pretty easily, just fighting the tightness of the alignment dowels. But if I had used something like silicone around the entire housing surfaces, it would have been much harder to open again without damaging something.
 

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Discussion Starter #15
Thanks Red O,

I may go with the 5/16" , or even some JB Weld :smile2:

For the tranny case halves I used "Permatex Anerobic Gasket Maker" comes out like a red jelly. Not sure what it all means, but it is what was recommended for my 2-stroke outboard that I re-built last winter.

In other news, I got the tires/rims separated. The inner tube may be OK afterall.

IMG_1159.JPG

The tubes are necessary as they are carrying the valve stems. There is a bit of rust on them and even inside the rim. So, I will take care of that then re-assemble
 

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If I have tire issues I always remove the tubes and add valve stems and use bead sealant, Also put the Green tire slime in all my small tires and have yet to have a issue, My only issue with tubes is if a leak does happen the only option is to pull the tube and that is a bit much in the snow, Tubeless in a pinch can even use fix a flat but the tire Slime seals leaks as they happen thus why I like it.
 

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Discussion Starter #17
Quick Update . . .

I got both a 5/16-18 (standard thread) and a 5/16-24 (fine thread) tap and matching hardware. Not sure which would be better to use . . . fine or standard thread. I am thinking the fine thread would allow for more precise tightening with less risk of over-tightening and ripping the threads. Not sure of that logic vs. a bigger thread of the standard thread pitch.
 

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I would probably use the coarse thread. Your existing bolt was likely coarse, 1/4-20, not fine, 1/4-28.

The coarse 5/16-18 requires a smaller tap drill (0.257) than the fine 5/16-24 (0.272), leaving more metal in the tranny case.
 

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Discussion Starter #19
Thanks, Red O :smile2: Standard thread it is. I sort of came to that same conclusion as well once looking closer at the threads.
Here are the new threads cut . . . I was able to bore about 0.55" into the casing abutment, then tapped the hole.

IMG_1160.JPG

I got the 5/16" bolt installed. I could only get a 3/4" bolt, whereas the original 1/4" bolt was 1/2" . So, I used a couple of extra washers to take up the slack.

IMG_1163.JPG

Now moving forward with the tranny installation.
 
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