B21 Front wheels locked up not moving HELP

[joefire611]

Hello All,
Looking for some help. Love my B21 but not today. My front wheels are locked up. They free spin when I lift the front end. Back wheels turn in 2wheel drive but not 4 wheel drive. I'm thinking something in the front drive systems is broken or jammed somehow.
Any Ideas?

Thanks
Joe

 

[rentthis]

If you raise the front tires and turn one of them, do you hear and strange noises? Grinding, clunking, banging etc.

Check both U joints. One may have turned loose and is binding. Hopefully, that's all it is.

 

[torch]

I'm a touch confused. The subject says the front wheels are locked up, but the text says they spin freely when off the ground.

With both front wheels off the ground, spin a wheel. If the opposite wheel spins in the opposite direction then the problem might be before the front axle. In that case, I believe you should be able to disconnect the front driveshaft and move the tractor in 2wd (ie: both front wheels will be able to spin the same direction).

However, if the problem is at the input of the front differential (eg: seized bearing), then the front wheels will continue to fight each other and the tractor won't roll even with the front driveshaft disconnected.

 

[joefire611]

If you raise the front tires and turn one of them, do you hear and strange noises? Grinding, clunking, banging etc.

Check both U joints. One may have turned loose and is binding. Hopefully, that's all it is.

Thanks for the advice. I will be checking the U joints when I get back home on Tuesday.

I will post an update then .
Thank you.

 

[joefire611]

I'm a touch confused. The subject says the front wheels are locked up, but the text says they spin freely when off the ground.

With both front wheels off the ground, spin a wheel. If the opposite wheel spins in the opposite direction then the problem might be before the front axle. In that case, I believe you should be able to disconnect the front driveshaft and move the tractor in 2wd (ie: both front wheels will be able to spin the same direction).

However, if the problem is at the input of the front differential (eg: seized bearing), then the front wheels will continue to fight each other and the tractor won't roll even with the front driveshaft disconnected.

Thanks for the advice. I'm hoping its not a seized bearing. I will be checking the U joints and D/Cing the front drive shaft when I get back home on Tuesday.

I will post an update then .
Thank you.

 

[joefire611]

Hello All,
Well I tried to remove the front drive shaft but was unsuccessful. I unbolted the bracket holding up the driveshaft but was unable to to create enough room to slide the shaft off.

With both front wheels off the ground, the opposite wheel spins in the opposite direction. It dose seem like the front wheels are fighting each other. When I engage the front axle to 4Wd I hear a crack/snap and it moves a bit until the wheels lock again. when in 2wd they do not move unless off the ground and then its in opposite directions.

Dose anyone have a video or pictures on how to remove front drive shaft?

Thanks
Joe

 

[torch]

The parts diagrams available on Kubota's website might give you a clue. You could also try kubotabooks.com to see if there's a service manual PDF available.

A quick google produced this:

at the lower drive shaft front you will find two clamps like radiator clamps over a rubber boot. Remove these slide the boot up and you will see a two inch splined coupling. In the center of that coupling will be a small roll pin. Knock out the roll pin and the coupling will slide back to allow removal.

 

[Mark15]

Hello All,
Well I tried to remove the front drive shaft but was unsuccessful. I unbolted the bracket holding up the driveshaft but was unable to to create enough room to slide the shaft off.

With both front wheels off the ground, the opposite wheel spins in the opposite direction. It dose seem like the front wheels are fighting each other. When I engage the front axle to 4Wd I hear a crack/snap and it moves a bit until the wheels lock again. when in 2wd they do not move unless off the ground and then its in opposite directions.

Dose anyone have a video or pictures on how to remove front drive shaft?

Thanks
Joe

The wheels moving in the opposite direction of each other is normal operation of the differential. The wheels can only turn together in the same direction when the driveshaft is rotating as well.

This tells us the wheel bearings, axle shafts, and differential spiders gears etc. are not the issue. Your issue is somewhere between the ring / pinion gear and back towards the transmission.

Figure out how to remove the drive shaft (sorry I am not familiar with your specific model). If the driveshaft looks fine, this will help you isolate if the issue is with the ring / pinion or with the transfer case / transmission.

 

[joefire611]

The parts diagrams available on Kubota's website might give you a clue. You could also try kubotabooks.com to see if there's a service manual PDF available.

A quick google produced this:

thanks
I'll give it a try as soon as i can get back under it.

 

[100 td]

Front Wheel Drive Propeller Shaft
1. Loosen the clamps (1) and slide the propeller shaft cover (2) to
the rear.
2. Tap out the spring pin and then slide the coupling (3) to the rear.
3. Remove the bearing holder support mounting screws, and then
remove the propeller shaft with bearing holder support (4).
(When reassembling) . Apply grease to the splines of the propeller shaft.
(1) clamp (3) coupling
(2) Propeller Shaft cover (4) Bearing Holder Support