B7800 fan belt replacement - Difficult?

riptides · May 21, 2012

Is this something I can do in an hour? I would probably have to loosen the alternator to get it off?

I managed to see a fray point, the unit has over 600 hours, so I do think it is time anyway.

I had to stop in the field and clean up the air intakes, so I noticed it. Did not see it on pre-flight.

I have big hands and am visually impaired. No comments on my mental aptitude for this task, please.

AStanton · May 21, 2012

If it's anything like the belt on my BX25, I would tell you to buy a bottle of aspirin first. I would also suggest only using 8pt sockets or box wrenches.
Good Luck

longshot47 · May 21, 2012

Look closely to see if there is sufficient clearance to fit the belt around the fan shroud/radiator assembly and front power take-off. Also, check access to the idler pulley adjustment. Loosening the radiator at the mounts and the upper hose might be necessary if things are configured as with others in the B series.
An hour might be optimistic

BobonKubota · Feb 3, 2013

I've been looking for someone with experience changing the BX 25 fan belt, sounds like you do. My problem was screeching and overheating, so I first tried to tighten the belt at the alternator, but it is at the max and I can't see any alternative but to try a new belt. I could get the belt off the alternator and around the fan blades, but it appears the PTO shaft needs to be disconnected to get the old belt off and the new one around it (?????????). I haven't found anything on line yet, and I don't have a detailed repair manual. If you know where I can get the latter, and especially if you can talk me through what needs to be done, I would greatly appreciate your help!

azbinder · Feb 3, 2013

Three bolts in the drive hub on the end of the crankshaft. Take the bolts out of the hub and slide hub rearward slightly on the splines. Should leave enough room for the belt to slip through.. You will have to work the belt around the fan, but it is possible.

BobonKubota · Feb 4, 2013

azbinder said:
Three bolts in the drive hub on the end of the crankshaft. Take the bolts out of the hub and slide hub rearward slightly on the splines. Should leave enough room for the belt to slip through.. You will have to work the belt around the fan, but it is possible.

I appreciate the advice, thanks! Any ideas on how to get a repair manual? The book that comes with the tractor is pretty useless, and the Kubota website doesn't appear to want you to have one.