MM60rse Gear box bearings bad

[Green Tea]

As a heads up, my SC2400 mid mount mower gearbox went out this week. Traced down new gearboxes from Yanmar America Parts Department at 1-800-966-7685. The new gearbox part number is 1A7880-99900. Might be able to get other parts from them as well!

How much was it?

 

[Dave N]

Hi Everyone,
I need to do a gearbox rebuild of some sort also (gear oil leaked out), but I"m having a terrible time getting the nut off the output shaft to get the pulley off. I'm hoping someone can help answer a couple questions:

1. Is the the nut on the output shaft a reverse thread?
2. How did you hold the gearbox while removing the nut? I've been using the vise, but the whole bench ends up moving!
3. How do you keep the shafts from spinning while untightening? I've been using he driveshaft wedged agains the bench, but as much pressure as I'm putting on the nut, I'm afraid I'll bend something.
4. The gearbox turns freely one direction but binds in the other direction. Any insight as to whether that is normal (I don't think it is), and what it might mean in terms of the rebuild?

Thanks for any insight you could offer!

 

[Tractorable]

With one of these....

 

[Dave N]

Hi Tractorable,
Tried it with my pneumatic to no avail, hence my question about a reverse thread and holding the gearbox while working it. In fairness, my pneumatic impact wrench is old and was inexpensive to begin with, so it may not be hitting the nut hard. I'm picking up a new one on Saturday. I've tried to stick with corded electric and/or air tools. Batteries just have not worked out for me in the long run.

Any thoughts on the reverse thread and/or how to hold the box?

 

[CaptFerd]

Hi Tractorable,
Tried it with my pneumatic to no avail, hence my question about a reverse thread and holding the gearbox while working it. In fairness, my pneumatic impact wrench is old and was inexpensive to begin with, so it may not be hitting the nut hard. I'm picking up a new one on Saturday. I've tried to stick with corded electric and/or air tools. Batteries just have not worked out for me in the long run.

Any thoughts on the reverse thread and/or how to hold the box?

Its not a reverse thread. Just going to have to get creative with locking it down. A second person, or mount it back to the deck and attach the drive shaft back to hold it. May have to heat it up. They usually come right off with the Impact but they are tight.

 

[Dave N]

Thanks CaptFerd. I got it off with the new impact wrench ("1100 ft/pds of bolt busting torque") and the torch. Four minutes with the torch, then 30 seconds of impact wrench repeated 3x. The pulley didn't want to come along peacefully either, but it's off. The inside of the box looked like the filings from a lathe. At first I thought "why are there springs in here?" Turns out it's just super tightly wound up metal filings. Not enough of the outboard output bearing left to even take in to match up.

I'm going to try to hunt down some parts from the diagram earlier in this thread. Thanks for help everyone!

 

[Dave N]

Hi Eevryone, For the sake of posterity and those who will come along later to this thread, attached is the configuration that is on my gearbox. The gearbox itself is made by Peerless, which if you are doing a rebuild is apparently different that Peerless Bearings. My configuration is closer to this: View attachment 525490

Oil seal 87A is an SKF 8648
Oil seal 87 is an SKF 11223
Bearing 88 on the input shaft is an R14 (no seals or shields)
Bearing 89 is an R12 (no seals or shields)
Bearing 88 on the output shaft is not the same as bearing 88 on the input shaft. It is a 6205C3.
Bearing 88A on the output shaft is a 62052RSC3

Total cost of the bearings and seals from the local bearing house was $71, and they are all Koyo and General bearings, and SKF seals. I'm going to guess they are better quality than the originals.

Happy Mowing!

 

[CaptFerd]

Hi Eevryone, For the sake of posterity and those who will come along later to this thread, attached is the configuration that is on my gearbox. The gearbox itself is made by Peerless, which if you are doing a rebuild is apparently different that Peerless Bearings. My configuration is closer to this: View attachment 525490

Oil seal 87A is an SKF 8648
Oil seal 87 is an SKF 11223
Bearing 88 on the input shaft is an R14 (no seals or shields)
Bearing 89 is an R12 (no seals or shields)
Bearing 88 on the output shaft is not the same as bearing 88 on the input shaft. It is a 6205C3.
Bearing 88A on the output shaft is a 62052RSC3

Total cost of the bearings and seals from the local bearing house was $71, and they are all Koyo and General bearings, and SKF seals. I'm going to guess they are better quality than the originals.

Happy Mowing!

Thanks looks to be the same box. Ive noticed over time that this same box has been used over and over on different applications. I recently restored a 1969 sears garden tractor that uses the same box on its mower deck. It has 2 of them one for each blade. The shafts are different on the outside but everything inside and out are identical. Your info is worth its weight in gold.

 

[Green Tea]

I got mine rebuilt by the Amish for $100.
In maryland all the tractor places said i had to buy brand new one for $800 ..Took it up to Lancaster county in PA and 2 werks later had my totally rebuilt gearbox!

Yanmar and Cub Cadet are no longer, and so are the parts. Bearings went out on the mower deck gear box and the box cant be found anywhere. Not even the Certified Yanmar dealers can get it. Now that my 3 year old tractor is in the same as a 1940s cant find parts category, I'm looking for Ideas on what to do to get it running again. Anyone ever rebuilt them? Or Is there a substitute? the model was an H1050-013 Peerless gear box.

(removed)