Kuhn GMD 500 questions

[rtimgray]

I just drug home a (used) Kuhn GMD 500 disc mower yesterday and went about the process of hooking it up to my DK 45. Overall, unit seems in good shape. I had to re-arrange a couple of the lower link pins to get it to line up right and also had to install a hydraulic hose.

Couple of questions:
1. I got the operator/assembly manual from the previous owner, but it doesn't have a parts breakdown. The Kuhn website doesn't have one available - at least not that I could find. Anybody know how to lay hands on a parts manual? A google search turns up several sites that list them, but they're all out of stock.

2. Any idea how old this unit it? It hasn't been used in quite a while, but was stored inside, so it's in very good shape. That's really just a curiousity question. I don't know if it's a current model or not.

3. I understand that the 4 and 6 disc models cross-over to a John Deere 240 and 260 mower. Did JD ever do a 5 disc model? I couldn't find that on their website either.

4. Lastly - how important is it to use the safety chain? When I hook it up as recommended, it seems to come perilously close to the PTO shaft. On our old Kuhn mower, we used the chain. On our new First Choice mower, we never have. Didn't know what most folks did.

I'm going to finish going over it this afternoon and try to cut a little with it just to try it out. I would welcome any comments or information.

Thanks.

Good luck and take care.

 

[Tx Jim]

IIRC JD never offered a 5 disc cutter. I'm sure you're aware that JD parts schematics are available online? I thought the safety chain was a depth stop to only allow 3 pt to lower to a set height.

 

[rtimgray]

I found the JD parts schematics online (thanks for the notice, though) and figures that *most* of the parts are going to interchange, whether it's for a 4 or a 6 cutter head, just trying to find the proper manual for future use.

That was my assumption about the safety chain as well. I always wondered if it was for tractors that had "lazy" hydraulics - we have an old Ford 4000 that tends to drift down after a while, so it would be good for that so you don't have to constantly raise the hitch.

I mowed about an acre last night and everything sounded good and it cut great. I changed the oil in the gearbox and bar before I cut and I'll probably change it again after I done and it's nice and warm. Belts are in good shape as are the blades - I've really got no complaints about it.

Thanks for the help. Take care.

 

[Bigfoot62]

I recommend that you buy JD or Kuhn blades. They will outlast any of the aftermarket copies.

Something to check: Inspect the plastic bushings on the front and back of the gearbox. You don't want them to wear completely through. Then it would be metal on metal.

 

[rtimgray]

Well, it looks like I'm going to need a parts list after all. I mowed for a couple of hours tonight and started hearing a clicking noise coming from the cutter bar. When I looked at it, I noticed the last disc on the bar (the tall one) was wobbly when I grabbed it. I removed a few bolts and it looks like a bad bearing. I looked at JDParts online and looked at the 240 and 260 mower diagrams and they look nothing like the GMD 500. Am I looking at the incorrect model of mower perhaps, or maybe the GMD 500 is significantly different than the 400/600. Anybody have any idea where to come across a parts list for this particular mower?

Thanks.

 

[Bigfoot62]

Try looking at the JD 265 mower. It should be the same as the 500, with just one more disc.
I know that I can walk into a Kuhn dealer and buy parts for my 265. It's exactly the same as the GMD 600. (but not the Gen 2, HD. Some parts on the Gen 2 are different)

 

[rtimgray]

Thanks for the help. I checked it out and it looks closer, but not the same either. My mower just says GMD 500, so I don't know if its a Gen 2 or HD or something different - all it says on the nameplate is GMD 500. The JD 265 is showing o-rings and snap rings in the disc assemblies and mine doesn't have any off that - it has a nut on the shaft that holds the gear on that drives the disc.

I did see that our local JD dealer is a Kuhn dealer as well - maybe they can help me sort this out.

Once again, I thank you for your help - and if I'm misreading some of the diagrams and it is the right cross-over, please forgive me. Thanks.

 

[rtimgray]

Just checked it out on Youtube and there is a series of videos where a fella has done exactly what I need to do with my mower - and there are indeed o-rings to seal the hub assembly to the gear case - it was getting dark last night as I was working and I bet I didn't see them. On the video he said that bearing is not sold separately from a Kuhn dealer, but he found one that would fit, although the OEM was a sealed bearing and the unit he found was not. I'm going to do a bit of research and see if I can find a sealed bearing like the original.

I still don't know if the 265 is the same or not - because I still don't see a nut on the end of the shaft that holds the gear on (again, I might not be looking at it right).

 

[rtimgray]

Well, good news and bad news after my conversation with the Deere dealer. The reason I wasn't seeing all of the other odds and ends is because they (JD and Kuhn) only sell the disc hub as an assembly - about $275 (ouch). After watching the videos on Youtube, I think I'm going to take a shot at replacing the bearing - I can't find the bearing locally, so I'll have to order one, but looks like I can get it delivered for $30 or less. The dealer has the hub available, so if I fail at replacing the bearing, I'll still have the more expensive option, and taking the part on and off is pretty easy.

So Bigfoot did direct me to the correct model/diagram, I just wasn't reading it right (once again, the problem with my computer is somewhere between the keyboard and the chair).

Thanks again.

 

[wmonroe]

Hopefully you can order the correct bearing and just replace it instead of the more expensive hub.