Bush Hog spline to hub play

Avondale · Jun 3, 2017

Good Morning,
I have a 10 year old Bush Hog SQ600 rotary cutter that has some slop/play at the hub, where it interfaces with the gear box splined output shaft. Is this a normal, fair wear and tear type event for this age and does anyone know how much is too much before replacing the hub? The mating ridges/grooves of the hub are somewhat rounded off while the shaft spline ridges are still fairly squared off. I've been told that the hub material is engineered to be softer than the splined shaft to reduce the likely-hood of damage that would involve a gearbox repair effort.
Thanks in advance for whatever help you can provide.
Bob

countrybumpkin · Jun 3, 2017

If your talking about the hub in the blade bar - stump-jumper, then there should be no play. Should be a tight fit.

JRobyn · Jun 3, 2017

On some (most?) of their stuff, Bushhog uses a weird tapered bolt to lock the drive hub (at least of slip clutches) onto the input shaft of the gearbox. My 286 hub was a little wobbly too. I punched the tapered bolt out and de-rusted it good with a wire wheel. I believe that at least part of its clamping force is intended to be from it ROTATING snugly into the groove around the gearbox input shaft as it is tightened. So if it's rusty, it won't rotate as designed. I put a film of lube on it when I reassembled and it does seem to be less wobbly now, but there is still some play.

Texasmark · Jun 3, 2017

I'd say if turns don't bother you keep at it but somewhere down the line time to upgrade. Obviously any wobble will just accelerate the destruction of the yoke.