I was driving my murray tractor and pushed the accelerator go go up a hill, next thing I know the pedal is stuck and the mower is in a smoke storm because of a locked pulley. These are supposed to be throwaway units, and there is a kit for 800$ that completely replaces the trans, total ripoff in my book. No warranty either. If I had to go that route I would get a new mower. Anyway I dropped the trans, opened it up and noticed the cap bolts were either loose or completely broken off. One came out whole, one broke below the surface, one broke flush, one broke with a stub(vice grip friendly).
You can see from the images below a scar in the case from the loose bolt..
Beyond that, the unit is now off to a welding shop to fix:
-The external actuator pin that broke when the bolt blocked the shift mechasim
-a crack in the case from from not seeing 2 bolts (kinda visible in pic #2 at the top
-removing the the broken cap bolts studs.
Now I'm wondering what oil is used to replace. You see the tar in the bucket, not pretty. This unit requires 2 oils, and they are separated by an RTV seal.
80W90 for the diff
Now the pump I'm not sure yet. There is a peerless pump oil kit, it is just branded mystery oil, cost about $40ish shipped. Now I'm reading everyone is using 20W50 synth motorcycle oil, or even 15W50 Mobil 1. The kit comes with an extra bellows, but mine is not leaking and looks fine. I noticed that the unit was getting a bit more sluggish over time, I guess that is due to that horrible oil. It is 15 years old, I installed an hour meter a few years ago, I would estimate 175 hrs on the unit.
I am going to use the special RTV for differentials, I had very good luck with it. Worth the extra few bucks. The case looks very porous.