Bottom seal replacement on a Woods BB720X rotary cutter

[flyerdan]

It appears that the new seal doesn't have any rubber contact with the shaft, I don't see how it can keep from seeping, unless there is a rubber contact area on the back that I can't see. I can understand the full metal cover, as that would keep long grass or twine that got wound up from abrading the seal itself. That has to be a nearly impossible area to clean out without removing the jumper.

 

[MinnesotaEric]

Bum knee wise, I got a staph infection and got opened up again, along with a 4-day stay in a hospital. The good news is that upon my return, I harnessed the power of OPP (Other People's Power, What were you thinking?) and got the stump jumper put back on after I cleaned up the interface. I then carefully torqued the 30x2mm castle-nut back on with a 1-13/16" socket to 1250 ft pounds (meaning I put the same 3/4" impact gun on it and let it rattle until I could shove in a 1/4 x3" cotter pin). With the cotter pin in, I trimmed the cotter pin to the right size with a cut-off wheel, properly installed it, and then fired up my tractor and put the rotary cutter back on the ground.

Apart from torquing the driveshaft retaining bolts, and filling the gearbox with (more) 00 cornhead grease, I have one more minor upgrade to perform before sending this attachment off to do work.

But staph infection, so everybody wants me to take it "a little cooler," but I like my planned upgrade.

 

[mllud]

Nice job. Leaning it against the tree gave access to both sides.
I did this job o my Woods Dixie Cutter years ago but couldn't remember enough to give advice. My replacement seal has held up well. I remember my bearing needed replacement.

Your good photos and description will help some future person doing this job.

Your cutter will last a lifetime if the lube is checked before each use. You already know that.
Corn Head grease works well in brush cutters. Don't overfill the gearbox. It can run hot if over filled.
Don't mess around with that knee. You need it to climb onto your tractor.
Get well.

 

[MinnesotaEric]

It appears that the new seal doesn't have any rubber contact with the shaft, I don't see how it can keep from seeping, unless there is a rubber contact area on the back that I can't see. I can understand the full metal cover, as that would keep long grass or twine that got wound up from abrading the seal itself. That has to be a nearly impossible area to clean out without removing the jumper.

The new seal is under the new shiny metal thingy that is all metal. The all metal thing is the seal protector, not the actual shaft seal. In so far as removing the stump jumper to clean up barbed wire, twine, and all the "I didn't know that was in my field" garbage that can get wrapped around the shaft, now that I've done it once, I will not fear popping off a stump jumper because it comes off easily with the right technique:

1) Loosen the nut
2) Thread the same nut back onto the shaft most of the way but do not bottom the nut out.
3) While applying force with a pry bar from the backside (as though you were trying to pry the stump jumper off), hit the nut with a heavy hammer.

Interference bits come off fast by the shock of a sharp hit. In fact, most pullers for tapered interference parts and drive clutches are designed to load up interference-fit parts and not meant to do all the work of actually removing parts. A sharp shock from a hammer is supposed jar the parts apart as I showed in that RZR secondary clutch removal video.

 

[MinnesotaEric]

I have now upgraded my rotary cutter so when I'm roading it, people coming up behind me get a giggle.

 

[MinnesotaEric]

For posterity's sake, and for the next guy who wants to see how to replace blades and adjust the slipper clutch on their Woods rotary cutter, here is a long format video on the subject. I will say this: in the video, I heated up the bent top link structure and straightened it because I do not have a hydraulic press. The softened metal pretty much bent back again and so I ended up straightening it and welding fish plating the bent areas to keep them straight. The fish plating is NOT in this video.

 

[MinnesotaEric]

And so there is one place on the internet for all my Woods rotary cutter activities, here is the video about fixing tail wheel damage.