B21 Clutch Problem?

[RobbieBones]

Yes, but I am curious why the clutch in the B21 (by at least 2 reports) ends up with a tractor that all of a sudden can't move without major mechanical noise. Most clutches start slipping and give you a chance to address it. Also, I don't understand why a clutch in a HST machine would wear out under normal use, it is simply a safety disconnect in my mind.

I feel the same way. There is a slight chance I hit the front dif drive shaft on a small rock. But back tracking my path I don't think it was possible unless the rock popped up and then back down. Looking at the service manual it looks like the shaft is suppose to be on a slight downward angle to were it meet the other shaft. I have to take a better look but mine my be straight. Not sure have to look. But I doubt I hit any rock.
The hydraulics all work that's how I maneuvered the machine into a better location.

 

[dfkrug]

Yes, but I am curious why the clutch in the B21 (by at least 2 reports) ends up with a tractor that all of a sudden can't move without major mechanical noise. Most clutches start slipping and give you a chance to address it. Also, I don't understand why a clutch in a HST machine would wear out under normal use, it is simply a safety disconnect in my mind.

Yeah, the clutch on B21s if for safety interlock and PTO control. Also, range shifting is easier when pushing
the clutch in. On my B21 project, it seemed clear that the tractor was used for a while despite an oil-fouled slipping
clutch.

B21s are known for trans problems. Forcing the range shift lever when it resists shifting can break things
inside. I once found a local rental B21 with trans problems, but they wanted too much for it.

 

[brain55]

Yes, but I am curious why the clutch in the B21 (by at least 2 reports) ends up with a tractor that all of a sudden can't move without major mechanical noise. Most clutches start slipping and give you a chance to address it. Also, I don't understand why a clutch in a HST machine would wear out under normal use, it is simply a safety disconnect in my mind.

They have a tendency to wipe the splines out of the disc. Not just B21's but B's in general. The last one I did in the field had done the same and needed the input shaft replaced at the same time.

 

[TomSeller]

They have a tendency to wipe the splines out of the disc. Not just B21's but B's in general. The last one I did in the field had done the same and needed the input shaft replaced at the same time.

Got it. Thank you.

 

[Gator6x4]

Sounds like the poster has a transmission problem. Straight gear tractors and Shuttle Shift tractors have a clutch. The poster says the "FORWARD and REVERSE" pedal feels funky. Never seen a forward and reverse pedal on anything except hydro-stat transmissions.

Taken from post # one.:
Putting it in neutral the noise is not as bad, put the clutch down noise is much worse. Is there a way to diagnose that it's the clutch not the tranny?

Forward and back pedal feels slightly funky but not sure if it's not because the clutch won't engage

 

[TomSeller]

Sounds like the poster has a transmission problem. Straight gear tractors and Shuttle Shift tractors have a clutch. The poster says the "FORWARD and REVERSE" pedal feels funky. Never seen a forward and reverse pedal on anything except hydro-stat transmissions.

Taken from post # one.:
Putting it in neutral the noise is not as bad, put the clutch down noise is much worse. Is there a way to diagnose that it's the clutch not the tranny?

Forward and back pedal feels slightly funky but not sure if it's not because the clutch won't engage

B21s have a basic HST with fwd/rev pedals as well as a clutch.

Clutch is only intended (in my opinion) to relieve strain on range gears as well as a safety disconnect. It should not be used to engage movement.

 

[brain55]

HST's create a lot of shock load on the clutch splines, the pedal gets used as an on/off switch. There's no clutch slipping to reduce the load.

 

[dfkrug]

HST's create a lot of shock load on the clutch splines, the pedal gets used as an on/off
switch. There's no clutch slipping to reduce the load.

My B21 was indeed a bit abrupt in both FWD and REV. All 4 of my JD 955s were, too.
The latter used a flex-plate to absorb some of the shock.

But many newer HSTs, not so much. The Kubota HST+ on Grand Ls are excellent. Even my
old Kioti CK is quite smooth in transition from stopped to moving. No jerking.

I once had a McCormick GX50, my only servo-controlled HST, and that was the smoothest
yet. There was a bit of a delay and ramp-up in motion after you hit the go pedal. Very slick.

 

[TomSeller]

My B21 was indeed a bit abrupt in both FWD and REV. All 4 of my JD 955s were, too.
The latter used a flex-plate to absorb some of the shock.
.

Interesting, I guess I baby mine. I don't like abrupt.

 

[100 td]

Does anyone make a clutch plate with springs in it as a replacement? Would one be worth it?