HELP! Did I do something really bad to my B7300?

[jrlichina]

The hydrostatic unit is self bleeding. Garden tractor units have the aforementioned bypass valve(via a lever). This is because the hydraulic motor output shaft is directly coupled to the axle. So the only way to move it safely and/or bleed the unit is by engaging the bypass and cycling the swash plate(direction lever). Put the gear selector in neutral then cycle the pedal forward and backward about three or four times. Then cycle the 3-point control a few times. If you reinstalled everything correctly(and it sounds like you did) it's just a matter of an air pocket. Then put it back in gear and it should operate normally. Recheck the fluid level once you get it moving and the 3-point working.

 

[JayC]

It has been a while since your first post about this issue. Did you ever figure out what was wrong with your tractor?

 

[Climber]

Folks, I was unable to get back to my tractor problem for a few days. Here’s an update on the situation:

I called Kubota, and talked to an engineer. His diagnosis from my description: the hydraulic system is air locked. The way he explained it, the pump is located towards the front of the tractor, and sometimes, when draining the fluid, the line leading up to the pump gets drained too, and the pump is not able to pick up the fluid. He suggested I raise the rear end of the tractor. If that did not help, he said to call the dealer.

Raising the rear end had no effect, so I called the dealer. The dealer also suspected an air lock, and suggested that I start the tractor, pull back on the hydraulic lever, and then blow some compressed air into the case to force the fluid up to the pump, until the 3PH comes up. I thought that sounded great, so I made a seal out duct tape, and blew some compressed air into the tank. I was not quite sure how long it would take, so I fiddled with it for about 5 minutes, but nothing happened, so I gave up. Then, I looked under the tractor, and noticed a rather large puddle of super UDT on the garage floor.

After a few choice words, and cleaning up that mess, I proceeded to determine where it came from. It appears to coming out of a tube that is open-ended, and points straight down to the ground. I am guessing it’s an overflow/pressure-relief type of mechanism, but I am not sure.

I will call the dealer again tomorrow. Meanwhile, if this rings any bells, I could use some more suggestions and/or ideas. I must say, I never thought a simple fluid change would cause me this much grief. Thanks to all who responded!

--Chris

 

[Climber]

HOT UPDATE!!!! I got it working!!!!

After logging on to post my latest update, I read the last couple of posts, and decided to run right out to the garage and try the suggestions:

I fired up the tractor, and kept my foot on the clutch for about 1 minute. Meanwhile, I cycled the hydro pedals forward and back a few times. Then, I tried to raise up the 3PH, and it came right up!

I cycled it a few more times, and then I went for a short ride. All symptoms have disappeared!

Again a big thank-you to all who replied. I'm sure glad to put this one behind me!

--Chris

 

[jinman]

Chris, that's great news. Isn't it nice to know someone here on TBN diagnosed your problem correctly when an engineer and your dealer couldn't? I can't give them too much grief though, I wasn't right either. /forums/images/graemlins/blush.gif

 

[Junkman]

Great news...... now to give you a definitive answer to your question..... "Did I do something really bad to my B7300?"... the answer is a resounding NO. Did you do something really bad to your ego..... the answer is a possible yes...... will you get over it..... definately...... will you forget it....... definitely NO..... The value of this site....... PRICE /forums/images/graemlins/grin.gifLESS!!!!!!!! Happy Motoring..... the Junkman is cheated out of another one.... LOL....

 

[Climber]

I am always amazed at the amount of collective knowledge and experience of the members of this forum. I was certain someone could help out.

I am a little disappointed in both Kubota and my dealer. Kubota was *very* quick to refer me to my dealer. My dealer was helpful, but overlooked what I now think is obvious. I am choosing to give them the benefit of the doubt, and figure that they thought I would know how to bleed the system. Although I must say: that procedure is NOT in the manual.

 

[Climber]

Well, my ego is definitely bruised, but I will survive. I admitedly don't know all that much about tractors, but I can follow procedures as outlined in the manual. It's a shame the manual did not go one step further and explain the bleeding procedure.

On the upside, I learned a whole lot from this experience. I am printing this whole thread and adding it to my manual!

--Chris

 

[jrlichina]

I'm rather surprised that Kubota or the dealer wasn't able to give you the bleeding procedure I outlined. It's a very standard practice/procedure. In particular the dealer since they service these machines, makes you wonder....

 

[skent]

if you want, i can email you a jpg of the revised manual pages.