# Kuhn GMD 700



## scrapiron (Mar 10, 2010)

Local junk man called me this morning , said he had one do I want it ? Paid just over scrap price for it. Been sitting in a barn for 15 yrs, locked up tighter than a frogs butt. Have to take it apart & get it freeded up. Take bar apart & soak in diesel fuef ?? Mower is in great condition just locked from sitting up best I can tell. Any suggestions ??

scrapiron


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## grouchy (Sep 19, 2009)

Can you tell where it is locked up? Is it the cutterbar or some part of the drive? I wouldn't think that it would lock up that tight (I never felt a frog's butt, though) just sitting in a barn unless it was wet in there and severely rusted. The locked up part may be why it is in the scrap heap. I would try to determine where it it locked before I took anything apart, especially the cutterbar. Are there any clues? No oil in cutterbar, Belts missing or worn due to misalignment? Can you see rust in any of the oil check or drain plugs? Is there any visible damage anywhere that may get you in the right direction?


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## Tim/South (Dec 12, 2011)

I would take the bar off and see if the gear box was free, kind of narrow own where to start and go from there.

I bought two Fella mowers one time and placed the good bar on the good gear case. We ran that mower for a few years.


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## RockmartGA (Jun 29, 2011)

I have seen disc mowers get rusty around the output shafts, which causes the cutter heads to lock down. You might try some penetrating oil and try working the outside turtle back and forth to free it up. If that works, it beats taking the entire thing apart.


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## scrapiron (Mar 10, 2010)

Just got the first, second in line, turtle off & gear out. The gear & adjoining gears look and feel new. It is locked up at the bearing or above.

The bar has no obvious damage from any impact. There is some surface rust but no major rust damage. The bolts & nuts are not seized, just rusty. I think the most damage was from sitting in the barn & moisture from the ground and air.

Should I soak the gear, bearing, shaft assembly in diesel,pb blaster, hagens brew, gasoline, or what ??

Going to go out and mark the rest of the turtles, for timing, and get the bolts loose.

scrapiron


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## grouchy (Sep 19, 2009)

Is it the pinion (or pinions)that is frozen up? Does the bar turn now? On a Kuhn mower the pinion gear is inline with drive gears. So when you took out the first pinion can you now turn the pto shaft? If you can then you would know the bar is the issue. It would just take one pinion to lock up the bar. You should be able to find any frozen up pinion by feeling backlash on the discs. If there is no backlash then it is probably frozen. It would just take one to lock the whole bar. I think the pinion bearings are sealed, I think i would just replace them and be done with it. Should be able to get them locally....


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## Mike120 (May 4, 2009)

I tried soaking parts in WD40 on a engine I rebuilt recently. It worked great. Filtered it through a shop towel/paint strainer and have used it a number of times since. I started using it to clean grease off my hands. Good luck Lindsay, hopefully you got a great deal!


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## mlappin (Jun 25, 2009)

Mix at a 1:1 ratio equals parts of automatic transmission fluid and acetone, best penetrating oil I've ever used.


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## blueriver (Oct 19, 2009)

Soaking (I like diesel fuel and used motor oil 50/50) and a little back and forth movement is probably all it needs ... that a great mower and I sure hope it don't take alot to free it up ... wish that was my junk man !! Be patient and don't force things, time is on your side.


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## scrapiron (Mar 10, 2010)

mlappin said:


> Mix at a 1:1 ratio equals parts of automatic transmission fluid and acetone, best penetrating oil I've ever used.


Thanks Marty : We have always called it Hagens brew, nasty stuff, works better than anything. I have seen it work when heating with a torch wouldn't work. Going to the hardware & autoparts stores in the morning. Will be soaking parts in it by 9 am .

scrapiron


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## scrapiron (Mar 10, 2010)

Grouchy : Thanks

Yes all the pinions are froze up. Gears between each pinion are free. I can't get to the bearings yet on the center 5 I have removed. Have not started on the end hi hat turtles. All the gears are in great shape, could not find any metal in the bar, used a cow magnet and a extend a magnet. Both came back clean. Oil in bar is at correct level and looks new.

I am thinking that it is the pinion above the bearings is rusted ?? Everything that is/was in the bar looks new. Thinking soak each piece and try to free it up ???

scrapiron


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## midniteplowboyy (Jul 1, 2010)

Take all the discs off and cut all the Bahia Grass and hay string off thats wrapped around the spindles. Then lube them up with some PB-blaster,ect,,. Get you a pipe wrench and gently rock each spindle back and forth between the gear slack, you may have one thats really locked up, or it maybe that every spindle is just barely seized. Since you got the inboard spindle out, fill the bar full of diesel, this may help lube the bottom sides of the other ones.

I flush my bars with diesel the beginning of every season or after a bearing goes out, I put magnetic drain plugs in the fill plug location and check them everyday for oil level and metal. I try to take all the disks off and and remove grass/hay string at the end of every season and lube the out side of the bar with diesel, sure makes a difference next season, but some years I'm to busy and regret it later.


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