On 3 Jul 2005 16:56:17 -0700, wrote:

I have an old 6 foot or so bushog of my dads I am trying to fix. The
mount for the gearbox was broke. Welded in some new metal and new
bolts. Did a good job. Went to mow with it in just a tall grass field.
I turned it on in my mowed yard and I could see the blades turning.
First went into the tall grass form the yard and it mowed good..... for
about 3 feet, then it is as if the tall grass slowed down the mower.
Brought it back up to the house. I can still turn the stump jumper and
plades even with the pto on. (And of course the tractor off). The nut
holding on the stump jumper I could turn. SOmeone has welded the nut on
the bolt. I could still turn the nut with a wrench.

Any guesses what is wrong. I have never worked on one of these. I guess
my next step is to take the stump jumper off, right?
I have a bush hog that's seen lots of use and abuse. So much that the
frame broke at the mounts where the gearbox bolts up. I considered
removing everything and fixing it proper until I realized how hard it
would be to remove the big disc that the blades bolt to. Instead I
welded the gearbox to the frame while repairing the frame. Is this
disc what you are calling the stump jumper? If it rotates, and the
bolt running through it rotates with it, then the problem is probably
in the gearbox. Can you get a cover off? If the bolt rotates while
the disc doesn't then it's probably a key that is sheared between the
bolt and disc. I'll bet it's a key or a pin in the drive, maybe where
the driveshaft is coupled to the gearbox, that's sheared. I have
sheared the pin in one of the couplers that is made to shear instead
of breaking gears in either the tractor or bush hog gearbox.
ERS