So this project started out as routine maintenance but turned into a real PITA and not sure if the problem will persist with other 60 MMM but perhaps a heads up. While preparing my 60 auto connect MMM off my 1025 for winter hibernation I noticed the belt had spots of irregular wear. Upon inspection of the pulleys I noticed severe rusting in sections of the 3 spindle pulleys and a small amount on the right angle gearbox pulley and almost none on the tensioner pulley. Since purchase I keep the tractor and all implements in a heated shop. The options were fairly simple, replace the pulleys or try and clean them up. I went with trying to clean them up for now.
Unusual belt wear
When I removed the belt, in order to remove the pulleys, I noticed that the blades spun easy, but definitely sounded dry, although I just greased them prior to noticing the belt wear. I needed to remove the spindle nuts and the right angle gearbox to so I could work on the pulley. When I tried to remove the spindle nut it was beyond tight. This is s 30mm nut on the top of the spindle(opposite end from blade) I tried a ½ drive air impact with no luck, tried a ¾ electric impact, no luck, switched to a 30” breaker bar with a 2x cheater and managed to budge the first one loose. But unfortunately one spindle nut would not come off using any non destructive measures and I did not want to use the heat wrench yet. I am going to borrow a ¾ air impact from my buddy to hopefully get the last nut off.
The pictures show the severe regional rusting on some several pulleys. I am not certain of the cause of this, but have two theories. One is there was an issue with what appears to be cadmium plating or the rinsing of the acid wash used in that process both unknown. Or, is the fact this tractor was purchased in mid 2015 as a leftover 2014 and was sitting outside for 6 months, hence causing issues with where the belt was against the pulley with trapped moisture for months. Really though with my knowledge of cadmium plating and some extreme applications we have spec’d it, the second scenario would not occur if the plating were good. Basically I have no idea why this happened.
Condition of mower is like new, no reason to see severe rusting anywhere
Severe rust on pulley
Pulley after using a wiz wheel on it to clean up rust
Added a coat of paint for some protection
Next big concern, lubrication:
After removing the center pulley I buffed the rust off with a 2” wiz wheal and they came out pretty good, there are still some pits there but I don’t want to remove much material from the pulley. Now is there things get really concerning. I pulled the spindle out the bottom to take a look at the lower seal and bearing and I discovered NO fresh GREASE is at the bottom. After some inspection I see there is only one grease hole to get the grease to the bearings, and that hole is above the top bearing between the bearing and seal, where it should be for the top bearing. However, in order for grease to get to the lower bearing it must push through the upper bearing (forcing through small areas between the ball cage) and travel behind the spacer several inches and then get to the lower bearing. If any pressure develops it will push out the upper seal. I wondered if I just have not been adding enough grease so I reassembled the spindle and pumped 15 pumps of grease in... I took the spindle back apart and as you can see from the image grease pushed out of the top everywhere but nothing came out the bottom. I put it back together and decided to pump until I got back pressure indicating it was full and pushing against the seals. I put in a few more pumps in and the grease gun handle was tight, I forced a couple more pumps in and took it apart again. This time I noticed the top seal had pushed out about .05, as one would expect, but still no grease at the bottom bearing.
After removing pulley this pict shows the grease has come out around the seal in the top but still no grease showed up on bottom
Picture showing all the grease pushing out the top and pushed the seal
Picture of lower bearing after adding max grease you can see there is only some original grease present.
I considered putting the spindle in the lathe and drilling the grease hole and a new cross hole at the bottom to get grease out at both ends. However, after measuring I discovered there is not room to get a cross hole between the bearing and the seal where it needs to be because the seal sits tight to the bearing. All spindles demonstrated the exact greasing scenario where I could not get grease through them. With all this I ended up packing the lower bearings by hand. It’s really not a bad job to pull the spindles on this deck providing the nuts come off. Maybe it’s not worth trying to do anything with eh spindles but rather changing the service to pull the spindles once a year. I also wonder if the factory grease has turned to paste and it’s all packed up behind the bushing too stiff to push fresh grease through all the small spaces?
I removed the other pulleys and dressed them up as well, but unfortunately one spindle nut would not come off using any non destructive measures and I did not want to use the heat wrench yet. I am going to borrow a 1” impact from my buddy which should get something moving. I will remove one seal and bearing after I get the last spindle off and have a look at the grease inside.