Repairs What caused this hole in the diff cover?

[Psychlopath]

Snapper 33114S:

The right hand differential cover has had a hole worn in the inboard cover by the chain and sprocket.

What had originally appeared to be a crack turned out to be something much larger after removal and inspection.

The whole assembly is waiting for a trip to the parts washer tomorrow, so I can try to compare it to the diagram on Parts Tree; but before then, maybe someone can give me some insight. The fender doesn't look to be bent, which seems like it could cause the sprocket to be out of alignment, but since I dont have anything to compare it to I can't be sure. The part of the diff cover around the sprocket is worn thin enough that I have no clue if it was bent before I got it and needs to be replaced anyhow, so maybe that'll fix it, but maybe someone here knows for sure.

Here's a picture of the cover with it's hole:



Also, anyone happen to have a measurement from a new chain over 5 or so links, so I can measure mine and see if it has stretched?

 

[gfp55]

Snapper 33114S:

The right hand differential cover has had a hole worn in the inboard cover by the chain and sprocket.

What had originally appeared to be a crack turned out to be something much larger after removal and inspection.

The whole assembly is waiting for a trip to the parts washer tomorrow, so I can try to compare it to the diagram on Parts Tree; but before then, maybe someone can give me some insight. The fender doesn't look to be bent, which seems like it could cause the sprocket to be out of alignment, but since I dont have anything to compare it to I can't be sure. The part of the diff cover around the sprocket is worn thin enough that I have no clue if it was bent before I got it and needs to be replaced anyhow, so maybe that'll fix it, but maybe someone here knows for sure.

Here's a picture of the cover with it's hole:

View attachment 22128

Also, anyone happen to have a measurement from a new chain over 5 or so links, so I can measure mine and see if it has stretched?

What does the nylon thrust washer you like? Looks like the nylon washer wore thin and hub&sprocket weldment and chain wore into the cover. I can't believe there was that much torque on the chain to have stretched it. If there was your sprockets teeth would be worn down also. Let us know what you end up doing with it.

 

[Mow Joe]

I've seen and repaired this many times. What has happened is that the thrust washer (metal hex washer) on the left side broke and fell out inside the boot. This causes a massive amt. of end play and the chain rubs the diff case, eventually wearing it through if not caught in time.

 

[gfp55]

I've seen and repaired this many times. What has happened is that the thrust washer (metal hex washer) on the left side broke and fell out inside the boot. This causes a massive amt. of end play and the chain rubs the diff case, eventually wearing it through if not caught in time.

The parts breakdown shows (nylon thrust washer) It should do metal in my mind. I may be looking at a different parts list then you. I don't see that the chain can be stretched do you?

 

[Mow Joe]

I'm talking about the metal hex washer against the bearing/bushing on the LH side, not the nylon one that slides over the hex tube. I never ran into a chain I thought had stretched any significant amt. Some wear in the bushing inside the hex tube may give the chain some slack, making it loose and seem like it had stretched. The chain itself is not very problematic at all. I probably rebuilt 100 of them back in the day, seldom did I replace the chain.

 

[Psychlopath]

Looks like I'm working against a few issues.

First, there's not a Nylon washer or spacer involved with what I have, so that's gone away and could be part of the issue.

Second, on the left hand fender, it appears that the steel axle bushing had worn through at one time and let the axle shaft ate into the fender. It looks like a new bushing was installed and welded into place.

It seems that with that bushing having been munched as much as it was, it would torque the sprocket and chain into the diff cover; I bet that caused wear on the Nylon bushing and took that out of the picture and the wear just went on from there. I think that the left fender has been repaired so that it's OK 'till the current bushing shows wear and needs a replacement and when I get everything cleaned up later tonight, I can probably weld a repair onto the right fender.

A new one isn't expensive but I'll hold off on ordering the nylon bushing 'till I see if I can repair the cover.

Can you tell me which reference number the bushings/spacers you guys mentioned is in this diagram? I don't have a Nylon one and I'm not sure I have the metal one MowJoe mentioned either.

I don't see that the chain can be stretched do you?

Maybe stretch isn't as important as I thought; but if I can stretch the chain on a mountain bike, I figured the one in there could stretch. If it's not a big deal, I won't worry about it.

 

[Mow Joe]

The part I am talking about is actually not in this breakdown, since it is not in the differential. Ref. #6 is the same part, but there are two of them. The other one goes in the exposed end of the hex tube, against the LH fender bushing. Nylon washers are inserted between the hex washer and bushing to take up the end play. I'm guessing that when that fender repair was done, the hex flange washer and nylon washer/washers were lost/discarded or whatever. They may have broken due to the increased stress that the worn out bushing caused. The PO may not have known they were even there.

 

[Psychlopath]

Well, I got the parts cleaned up and I can't find any nylon parts/washers/spacers except for what appears to be something plastic-y in the planetary gear set.

So I have been going through the exploded drawings I've found online and trying to compare what I do have with what they say that I should have and have made an order with Parts Tree. Several washers and spacers, along with a new left fender and a differential cover are on their way, along with a new shift ball for the speed selector handle.

I'm starting to think this mower wasn't the stellar deal I thought it was; it's been ridden hard and put away wet often.

On my next weekend in a few days, I'll do more comparison and buy a few more parts if I need.

If anyone has a parts diagram that shows the Nylon spacers that have been mentioned, can you post it up here?

 

[gfp55]

Well, I got the parts cleaned up and I can't find any nylon parts/washers/spacers except for what appears to be something plastic-y in the planetary gear set.

So I have been going through the exploded drawings I've found online and trying to compare what I do have with what they say that I should have and have made an order with Parts Tree. Several washers and spacers, along with a new left fender and a differential cover are on their way, along with a new shift ball for the speed selector handle.

I'm starting to think this mower wasn't the stellar deal I thought it was; it's been ridden hard and put away wet often.

On my next weekend in a few days, I'll do more comparison and buy a few more parts if I need.

If anyone has a parts diagram that shows the Nylon spacers that have been mentioned, can you post it up here?

I guess I full of --it. The exploded parts drawings that you are showing are not the same as what I was looking at, so I've been just making things worse, sorry about that , I didn't mean to do that. It looks like your getting all the help you need, I out of here.

 

[Mow Joe]

Go here

Snapper Series 4 and 5 Parts Manual - MyTractorForum.com - The Friendliest Tractor Forum and Best Place for Tractor Information

Click on that link, which is the manual for your mower. On page 3.7, reference #s 28 & 29 are the washers used to adjust the axle end play. Note that #29 is the same part# as #6 on page 3.5. I see that there is also a notched washer listed. I doubt that anyone will have those, since they are just the regular nylon washer with a chunk cut out so it could be slipped over the axle after the differential was reinstalled in the mower. We were instructed at service schools to just cut a chunk out of the washers with side cutters. I never knew there was a ready-made one available.