HELP!!! L4400HST PTO Clutch

dstig1 · Oct 21, 2010

I was mostly curious if you were running it super low RPM and maybe were bogging it down that way. Doesn't sound like that is the issue...

johnrex62 · Oct 22, 2010

The specs on the L4400 indicate the proper engine RPM for the PTO is 2600. I don't think running it at 2000 would prevent it from turning before it bogged the engine down, but you are not getting 540 at the PTO at 2000RPM.

tallyho8 · Oct 22, 2010

Randall
Thank you for the pdf. I will save it for future reference.

I got in touch with my Kubota dealer today and he told me that it WAS covered by warranty and that my warranty ends in 5 days.

I loaded it up and rushed it over to the dealer and I will know something next week.

dex3361 · Oct 22, 2010

Your welcome and keep us posted on the details.

doall · Oct 22, 2010

good luck. Hope its something easy.

tallyho8 · Nov 4, 2010

After a week the dealer phoned me and said it was fixed. He said all they had to do was adjust the pto cable. I said that could not have been the problem because the cable moved the lever all the way to the stop, but they insisted that it was fixed.

I brought it home, hooked up the cutter, tried it out, and nope, not fixed, pto still slipping.

I brought it back to them the same day with the cutter on and they tried it in tall grass and saw how it was slipping and said they will fix it but I haven't heard from them yet.

tallyho8 · Nov 8, 2010

I phoned the dealer today and they said they changed the oil and filters and that it "looked" like it was working ok. I asked if they cut any grass with it and they said they had no grass to cut so they couldn't test it.

I told them to put it on a pto dynamometer and test it and they said they don't have a dynamometer and that they have to send it to a little town 70 miles away to get it tested.

I wish I had brought it to the little town dealer instead of the big city dealer to get it fixed. Maybe they would know what to do. Now I have to wait another week for them to transport it to the other town to get it tested.

tallyho8 · Nov 12, 2010

Update: I checked with the dealer today. They said my tractor failed the dynamometer test and was only getting about 25 hp to the pto.

They have to split the tractor and probably replace pto clutch discs and it will be about another week.

I sure hope that this is not a common fault with an L4400 because I only have about 40 hours on this pto and can't imagine why it failed so soon. I would hate to pay for this job if it wasn't under warranty.

JC-jetro · Nov 12, 2010

tallyho8 said:
Update: I checked with the dealer today. They said my tractor failed the dynamometer test and was only getting about 25 hp to the pto.

They have to split the tractor and probably replace pto clutch discs and it will be about another week.

I sure hope that this is not a common fault with an L4400 because I only have about 40 hours on this pto and can't imagine why it failed so soon. I would hate to pay for this job if it wasn't under warranty.

Tally,

As the diagram clearly shows you have a hydraulic pto clutch. You do have one main clutch for the locomotion. You have two shafts, one solid and the the other one hollow, one for transmission and one for pto. The pto shaft is splined and is directly coupled to crankshaft/flywheel. Any time the engine is on the pto shaft is turning but not the pto final shaft. what couples the pto shaft to final pto shaft is a set of wet clutch disk. Now, if you engage the pto and the clutch pack is not compressed hard enough then you have slippage that even causes premature wear on clutch disk... not a good thing. just imagine you're going downhill and push the break pedal only 1/4 of it's full travel. Obviously, you can not stop because of not enough friction is caused. if you continue driving like that you will just burn off disk material against the rotor and things get hot. The coupling of PTO on some tractor is done electro hydraulically or mechanically. I think your pto clutch is slipping in your case and that's not good. it is either caused by incorrect adjustment or pto disk are worn out. The wet clutch pack should outlast a normal dry clutch, so there is good possibility of bad adjustment from the get go..I'll study the pto engagement or ask the dealer about it.

JC,

edit: I did go and took a look at the pto engagement cable. The cable operates a pto control valve (mechanical and not electro mechanical). I see adjustment there on the cable tension. I can not see the valve is two position or modulating, if the engagement cable does not fully open the valve then you can not get the flow pressure needed to press the pto clutch together all the way. if The valve is fully open thane you might not have the right hydraulic pressure to compress the wet disks together. two thing you need to know, one is if the valve fully opens and has no internal port restriction and secondly what pressure you have when the valve opens and if that pressure is within operating requirement of the pto clutch pack.

tallyho8 · Nov 13, 2010

Thanks for your explanation JC. What I am really worried about is that they will replace the clutch discs but not repair what caused them to go bad in the first place and when they wear out again next year it will not be covered by warranty and will be a $4000 repair job.

And after my tractor being in this shop for over 3 weeks, I have absolutely no confidence in this dealer.