[Electra96]

I have a Kuhn GMD700 mower and last year on my final cut (thankfully) it gave up. I lost the bearing and housing on the pulley side of the gear box. I took it apart and found it is a sealed bearing. I ordered the parts I needed from my JD dealer and waited about 2-3 weeks. Finally got them. When I looked at the replacement bearing I noticed it is labeled as a 2RS bearing which is a two rubber seal bearing. Well, it only had a seal in one side. I called the dealer and asked if he had another bearing and they said yup. I had them look at it and they said it has one rubber seal the other side is open. Well, I guess I know why my bearing went bad. With one rubber seal when the bearing gets hot all the grease will be lost as it runs out the unsealed side. Inside the gearbox there is an oil seal that goes on the driveshaft that has the ring gear on it. This prevents slung oil from getting to the sealed bearing. The other side is an open bearing that gets its lube from slung oil. I have to assume that since I ordered the replacement bearing and came packaged in a Kuhn wrapper that the original bearing only had one seal also. I contacted Kuhn support and told them the same thing and asked how that bearing with one seal gets lubed. Never heard a word from them.

So, I looked up and ordered an SKF bearing with 2RS on it and it came with two rubber seals. I put that one in instead of the one from Kuhn with one seal. This is a total design failure.

I guess this is a public service announcement that you really need to monitor that pulley bearing as when it goes it probably will eat the hub on that side as well as the gearbox driveshaft.

I am totally disappointed in Kuhn for not responding with some sort of answer. This is a lightly used mower and I don't do commercial work. I only bale hay for my cows.

Opinions?

 

[Tx Jim]

I feel sorry for your problem. As a whole Kuhn farm equipment has a very excellent reputation.

 

[Electra96]

I feel sorry for your problem. As a whole Kuhn farm equipment has a very excellent reputation.

Yeah, I always thought so too. Kind of disappointed in them now.

 

[Jimmy Bartlett]

wouldn't the rubber seal go on the pulley (outboard) side and the un-sealed side be inboard where there's gear oil?

 

[Electra96]

wouldn't the rubber seal go on the pulley (outboard) side and the un-sealed side be inboard where there's gear oil?

Jimmy the inboard side is protected from slung oil by an oil seal that prevents that oil from reaching that bearing. The other side of the gearbox has a bearing that is lubricated by the slung oil.

 

[Tx Jim]

Sounds as if brg needed to be rotated in bore 180° before installation.

 

[Electra96]

Sounds as if brg needed to be rotated in bore 180° before installation.

That would probably be better but then the outside of the bearing with no seal is open to the elements and the hot grease would just drip out between the housing and the pulley.

 

[Tx Jim]

I guess I can't see the forest for the trees!!!
You 1st stated seal kept oil from lubricating the brg therefore I suggest to rotate brg 180° which would put seal location to the outside of brg & gearcase which as long as seal was good would keep oil in the brg. Can you please post a photo of the brg in your gearbox?

 

[Electra96]

I guess I can't see the forest for the trees!!!
You 1st stated seal kept oil from lubricating the brg therefore I suggest to rotate brg 180° which would put seal location to the outside of brg & gearcase which as long as seal was good would keep oil in the brg. Can you please post a photo of the brg in your gearbox?

Yeah, kind of hard to explain. Let me try again. The inner side of the bearing in my mind at least needs the seal to keep packed grease inside the bearing. There is a rubber seal on the gearbox drive shaft that prevents any slung oil from getting to the bearing so with that inner seal of the bearing being missing, when the packed grease in the bearing gets hot it will just flow out and the bearing looses it lubrication. The outer side of the bearing has the seal in place to keep the grease from running out the outside as it has a shaft coming through it to the drive pulley. I looked and a picture would not show that area as there is a pulley and a cover there. I am gonna try and post the parts breakdown. #20 is the shaft oil seal that prevents slung oil from getting to the bearing #18.