Kubota B21 Drive Shaft Seal

Horizonls · Nov 1, 2015

Parked my B21 in the shop last night to preform the maintenance on it today. Came out today to a puddle of hydraulic fluid under the tractor. It seems that grass/hay wrapped around the drive shaft from the clutch to the HST and took out the seal (at the clutch housing end.)

Anyways, I'm going to have to replace that seal and the only way I can figure is to split the tractor to get the drive shaft out. I tried driving the roll pins out on each end and compressing the shaft on the splines, but there isn't enough movement to get it free.

Anyone split a B-series before?

dfkrug · Nov 1, 2015

Mine was a 1998. The B-21 is not much like one of Kubota's B-series tractors.

http://www.tractorbynet.com/forums/...ta-b21-tlb-complete-driveline.html?highlight=

Horizonls · Nov 1, 2015

Dfkrug what would you suggest is the easiest approach to remove the drive shaft seal, should I split it at the clutch housing joint or start from the back or front?>

dfkrug · Nov 2, 2015

Did you go thru that whole thread I posted?

You will need to remove both the mainframe and hydraulic tank first. Then split the
tractor aft of the bellhousing/primary gear box.

The drive shaft out of the primary gearbox into the HST has seals at both ends. Do
you know which end is leaking?

Horizonls · Nov 2, 2015

Yes, I did go threw your whole post and am amazed at the work you did to put that back together that was a major accomplishment way to go. The seal that is leaking is the front seal coming out of the clutch/gear box and it only leaks a few drops but just the same is annoying and should be fixed right. I was hoping you would suggest that I could split it at the clutch housing without having to tear the whole rear end off. Do you think I could just remove the bolts that hold the front section of the main frame and split it with all the back bolts attached still to the main frame, therefore not totaaly removing the main frame?

dfkrug · Nov 3, 2015

Horizonls said:
Do you think I could just remove the bolts that hold the front section
of the main frame and split it with all the back bolts attached still to the main frame, therefore
not totaaly removing the main frame?

Well, that might work if none of the hydraulic hardlines get in the way. I did not do it that way
as you see. The manual says to remove the mainframe, tho I do not always do it the way you
are "supposed" to.

It has been what, 8+ y since I posted this? I do not recall all the details of this repair. The
hydraulic tank is unusual, and a pain to work with.....that part stands out.

Horizonls · Nov 28, 2015

I got the tractor split and replaced the drive shaft seal, but I think in the end it was a bearing plug that is just above the seal. It is made of plastic and had a crack in it that was letting oil leak, the new plug is made of metal so it will not crack. I changed the clutch and release bearing while I had it apart.