# How to remove the Stump Jumper on a rotary mower



## Curtis B (Aug 15, 2008)

The output shaft seal on my mower went out and I need to replace it. I have been fighting getting off the stumpjumper to replace the seal. I have tried beating from above ( through the hole for the blade nuts). Heat jumper around shaft and beat from above. There are holes in the jumper 6" out from the shaft on either side and I ran allthread through them and bolted up angle iron on to set a 6 ton jack on and jacked till the jumper bent and tried driving. Then with the jack putting tension on I tried heating again then driving. I am officially at a loss. 

And yes, I have removed the castle nut.

Any other suggestions before I cut it all out.

I would much rather a $20 fix than a $200 fix.

Thanks


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## OkieDavid (Jan 15, 2007)

I'll be watching this one close, I haven't been able to break the castle nut loose on mine yet LOL........


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## Bearfootfarm (Jul 13, 2006)

Try here:
http://www.tractorbynet.com/forums/search.php?searchid=1352494


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## farminghandyman (Mar 4, 2005)

Most likely you will need to put tension on it, like your puller set up, (I would sugest some type of large threaded shaft and nut to tension it) but then a good solid whack with a sledge hammer, on the top of the screw/shaft, I would think would loosen it, I think it is on a taper, If you look at the box in this URL you can see the taper splines,
http://www.northerntool.com/shop/tools/product_200331516_200331516
threads on the subject,
http://www.tractorbynet.com/forums/parts-repairs/126172-kk-stump-jumper-removal.html

http://www.tractorbynet.com/forums/attachments/192038-removal-king-kutter-stump-jumper.html

http://www.tractorbynet.com/forums/parts-repairs/99329-removing-stump-jumper.html


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## Bearfootfarm (Jul 13, 2006)

Also make sure there is nothing UNDER the plate when it comes loose, because they are HEAVY

If you can turn the mower upside down to do it, you'll be much safer


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## vallyfarm (Oct 24, 2006)

With "FARMING" on this one. If a few good whacks don't do it, try some heat on it. Heat on the outside evenly if you can. Just rember heat can loose the temper of the steel and make it brittle. Mike


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## Curtis B (Aug 15, 2008)

Well, still will not come. Tried flipping over and using an 8 lb sledge to stike with. Through the process the stump jumper bent, and I even put heat directly on the hub. Guess I am going to try and cut the jumper off and try to cut off the hub portion from the shaft. Hopefully the gearbox is still OK with all the abuse.


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## davel745 (Feb 2, 2009)

Just an idea. I don't know if it will work. Lay out the center of the stump jumper and then drill and tap a 3/4 inch fine thread hole and wind a grade 8 bolt in and maybe it will free the stump jumper. The hole must go through the stump jumper so the bolt pushes on the gearbox shaft.


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## Bret (Oct 3, 2003)

Is it possible that there is an invisable grease/dirt covered retainer clip holding something on the shaft? I found one on the front of the gear box after a day and a half of pounding and four letter word practice. When the clip was removed the shear pin holder came off easy. Not saying it's there for you, but worth a close look.


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## Bearfootfarm (Jul 13, 2006)

Do you know *what brand* of mower?


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## Curtis B (Aug 15, 2008)

I had been wondering about some sort of retaining ring, and looked for some time and could not find anything. The stump jumper has now been folded up and is pretty much toast from the pressure, so at this point it will do no more damage to just cut it off to see full view of the hub portion and shaft to try and carefully cut it off the shaft.

I have no idea what brand it is other than red.


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## davel745 (Feb 2, 2009)

CurtisB please let us know what you find. Thank you


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## agmantoo (May 23, 2003)

If you have a welder, weld a big 1/2 wide bead of welding rod around the entire outside center section of the hub that is on the shaft. It is essential that the bead be continuous with not gaps. After welding let the weld cool. This procedure will expand the hub and the weld will not permit the hub to contract during the cool down. This process works great on friction fit bearing races as well. Just remove the outer race and weld the bead on the inner. The inner can be removed by hand afterward.


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## Curtis B (Aug 15, 2008)

Well, I was able to cut the hub off of the shaft (it was pure rust holding it on) and have been searching for a new stumpjumper, with very poor results. Apparently I have a real oddball mower. It has a 12 spline 1.5" shaft and the blade bolt holes are 11.5" centers. 

The closest I can find has 13.5" centers. I can't think of a reason that it would make a difference, other than the hole location on the mower for removing the blades, and that would be easly modified. Does anyone know if the gears in the gearbox of a 5' mower are that different from brand to brand that a 1/2" radius difference would affect operation?

Also, do they measure the diameter of the hub at the top of the splines or the bottom of the splines. Measuring the ouput shaft it is 1.55" and the vallies of splines are 1.625" The possible replacement shows 1.625, but does not specify at what location, and of course the folks have no clue when you call them.

If anyone wants I can post pics of the headache.


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## davel745 (Feb 2, 2009)

Maybe you could have the !3.5 inch stump jumper re drilled for to the 11.5 diameter so the blades will fit. I don't know about the splines.


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## davel745 (Feb 2, 2009)

What brand of mower is it?


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## oneokie (Aug 14, 2009)

Look at the items on this page: http://mower-blades.agrisupply.com/...od=and&view=grid&modaf=r:cat:rotarymowerparts


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## davel745 (Feb 2, 2009)

Try here too.

http://www.hydroponicsonline.com/st...n-Stump-jumper-for-40hp-Box_170281805590.html

Have you had any luck getting a replacement part?


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## GoldenCityMuse (Apr 15, 2009)

I feel for you on your project.


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## davel745 (Feb 2, 2009)

CurtisB How are you doing with the stump jumper problem?


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## Curtis B (Aug 15, 2008)

Still no luck. Nothing I have found will line up at all. I even looked at getting a new gearbox, but have found that the mounting hole locations are just right so that I would have to completly rebuild the mount for the gearbox, essentially build a new mower. Right now in my free time I am tring to research the gearbox manufacture to see if maybe they offer a different output shaft. This is a perfect example of why to buy name brand equipment. Had it been a king kutter I would already have it going.


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