Hydrostat/pto problem

[harpo]

Hi, I've got a JD 4300 w/ hydrostat drive. I loaned it to my brother to chip up some limbs with the pto driven chipper. While he was operating it the pto quit working, then shortly afterward the Hydro drive (both forward and reverse) quit working.
Does anyone know what kind of problem I have?
The only thing I know he was doing wrong was not keeping the pto drive shaft to the chipper level while he was operating the chipper(he was just setting the chipper on the ground).
Thanks for any help.

 

[kennyd]

My first thought would be to check the seat safety switch or the range selector safety switch. Short of that being OK I think we need more details...

Does the engine start OK?
Does the engine bog at all when trying the hydro pedals?
Is there any "feedback" in the hydro pedals?
Does the PTO light light?
Can you turn the PTO shaft by hand?

 

[harpo]

I don't have the tractor to check all of these things right now. My brother is hauling it over to my house tomorrow.
I do know that the engine starts and runs OK. No bogging when depressing the pedals. Not much feedback in the pedals, they mash to the floor pretty easily.

 

[RogerH]

Take a look at the coupler on the engine flywheel. It will be a disk with a hub that connects to the hydro shaft. It is possible that this coupler failed and is not even turning the hydro shaft. Put a paint or marker dot on both the coupler hub and the hydro shaft, start the tractor and see if both are turning. Using a mirror and flashlight should enable you to do this easily and safely.

 

[harpo]

Thanks for the ideas. I am still waiting to get the tractor back. I should be able to check some of these things this weekend. I'll post back in a couple of days, after I have a chance to look at the tractor. Thanks.

 

[harpo]

Got my tractor back today and checked the engine to tranny connection. That appears to be the problem, thanks RogerH ! There were some chunks of black rubber that I pulled out of the hub and the transmission shaft is not turning. So now I guess I just need to repair this connection and hope there is not something more serious that caused the failure. Is this a difficult repair? What is the procedure? Thanks again.

 

[RogerH]

Fixing this problem is not trivial. The coupler will have to be replaced and that involves splitting the tractor at the engine to transmission housing joint. It has been several years since I did this, but briefly you have to support both the engine and tranmissions sides of the joint. I recall the mechanic I worked for had some special stands that we bolted on to each half. The engine to transmission bolts will need to be removed along with any linkages, hydraulic lines and I think wiring harness that spans the joint.
I seem to recall that with all the right tools and the other guy that had done this before, it took two of us about 4 hours to do the job.

 

[harpo]

I suspected it would involve splitting the tractor, though I was hoping it wouldn't. I went to my dealer yesterday to buy the new part, but they could not find it on their computer or in their cataloges. Wants me to bring it in so they can put their eyeball on it.

 

[dirtworksequip]

harpo, what if anything do you suspect may have caused the failure? Or has this been a problem with the ehydro's?

Sincerely, Dirt

 

[harpo]

Dirt, the only thing I can think of that caused the failure is a heavy load on the pto. I don't think this has been a problem with eHydo's in general. My dealer has never replaced one of these couplers. I just got lucky I guess. My tractor only has 320 hrs on it, so I don't think it is age related.
I could use some help finding this part (the coupler between the engine and transmission on a JD 4300). What is the correct name for this part? I can't find it at JD Parts online.

 

[Mighty Dodge]

Check out the John Deere parts catalog
John Deere - Parts Catalog


M.D.

 

[harpo]

Mighty Dodge, I have looked at this parts catalog several times. Took another look and noticed that the torsional damper located behind the flywheel substitutes for several other part numbers. I guess this replaces whatever I had. It didn't look the same so I didn't think it was the right part.

 

[RogerH]

Thanks to the other posts, some of my memory is being restored. You described pulling out chunks of rubber from the coupler. That means the coupler you have is much thicker than the replacement coupler. Therefore in addition to the coupler (or torsional damper it appears it is called) you will also need the spacer. Looking that the parts catalog (thank you for the link) you will need to order both the torsional damper LVA13911 and the spacer LVU11630. The spacer installs between the flywheel and the torsional damper so that the hub ends up in the same location as before.

 

[kennyd]

harpo, what if anything do you suspect may have caused the failure? Or has this been a problem with the ehydro's?

Sincerely, Dirt

This is a 4300, so it does not have E-Hydro, it has the mechanical linkage to the pedal. The E-Hydro started with the xx10 series (4310, 4410, ect.)

 

[Brimstone10x]

I believe Deere had a fix as fail pip on these when they were new . I replaced several of them. do you have a 3x3 steel block as the center of the hub? it makes a nice paper weight. happy splitting.

 

[jd110]

The correct name for this part is a torsional dampener. It is part number LVA13911. I have attached a picture of the part. It is item number 3. You will also need items number 1, 2 & 4. The new dampener will be a different style from the original and is more durable. Item 1 is 19M7662 bolt and four are needed. Item 2 is a washer 24M7096 and four are needed. Item 4 is a spacer # LVU11630. Good luck! Ask your dealer to look up bulletin number 00-11-35-07. It will explain the differences. OOPS! I didn't look at page two of the post! sorry!

 

[harpo]

Thanks for all the help everyone. Dealer said all I needed was the damper and not the spacer. I'm glad you guys actually know something about it (been there done that). I would hate to get the tractor split only to find out I needed to order more parts. I guess it is good parctice to put in new bolts even if the old ones fit. Dealer wanted $715 labor so I told him I would try it myself. Oh yeh, the old hub has the big square metal block in the center.

 

[RogerH]

I really think that you will need the spacer part to do this correctly. Without it, the tractor will run, but the coupler splines will not be fully engaged with the HST shaft splines, and the durability may be reduced.

As a check, when you remove the coupler put it hub down on a table beside the new one (also hub down). If the surface that mounts to the flywheel is is the same height for both, the spacer won't be needed. I am almost positive though that you will find they are different heights and the spacer will be required.