Kubota L3650 WET Clutch

[ldozier]

My L3650 with a wet clutch just stopped moving. The engine runs, all hydraulics work, all the gear shift and clutch pedal feels normal but nothing moves when the clutch is released. Obviously something came loose in the internal drive. Any one with experience or where can a get a repair manual

 

[mbu]

Here's some good information regarding the "Ever Clutch" - it may be helpful to you. It's taken from the following link...


http://www.tractorbynet.com/forums/kubota-owning-operating/168804-ever-clutch-follow-up.html

Ever Clutch in more detail

No one can say what Kubota engineers were thinking when they created this clutch system, however, I find it suspicious that the Hydraulic Shuttle system with the single dry clutch (HDT) appears to be almost identical to the Ever Clutch system (HDT-W). And I dont know if there was any model year order to these being available, but it seems almost like one day one of the engineers said: ya know - why dont we use the hydraulic shuttle system as the main clutch and use the dry clutch for the PTO. They would have then created a new control mechanism, probably beefed up the clutch packs a little and there you have it? or, possibly it could have gone the other way after experiencing difficulty with the Ever Clutch.

The Ever clutch itself (again we are talking inside the transmission here) is similar to the clutch packs found inside an automatic automotive transmission. It consists of a round metal housing that has a forward side and a reverse side (see attached pics). The forward side consists of 5 forward clutch discs and 5 metal plates and the reverse side consists of 5 clutch discs and 5 metal plates (see pics). There is a forward gear and a reverse gear located at either end of the respective clutch packs.

This is very difficult to explain in words But basically the metal discs are held to the metal clutch case/housing via 6 tabs on the OD of the metal disks allowing them to slide in and out. There is a clutch disc in between each metal disc and the clutch discs are splined on the ID and attached to the metal gear on the end of the clutch pack they can also slide. So basically the gear and clutch housing can rotate independently until there is pressure applied to the clutch pack which ties the gear and housing together. Got it..?

The pressure to the clutch packs comes from a piston in the center of the housing. There is a forward one and reverse one that push out from the center toward either end. These pistons are pushed out by hydraulic pressure pushed in between the piston and the center of the clutch housing. When there is no hydraulic pressure the piston is held inward away from the clutch packs with a spring.

Hydraulic pressure comes from a hydraulic control box mounted on the left of the transmission under the left foot rest. The control box is fairly simple in concept provide pressurized hydraulic fluid to the forward clutch pack or rear clutch pack as well as the lubrication/cooling passage. In design this control box is quite complex due to having to regulate the hydraulic pressure for smooth clutching and shuttle take off.
- The control box has three outputs Forward, Reverse, Lubrication. There is always fluid traveling though the lubrication passage to keep the clutch cool. The forward or reverse passages only get fluid pressure when the clutch is engaged to forward or reverse. In neutral and/or with the clutch pressed in all of the available fluid pressure is diverted into the Lubrication passage.

The shuttle control lever operates a diverter valve within the hydraulic control box. There are three positions.
- Neutral: Pressurized hydraulic fluid is sent to the lubricating port. No fluid pressure is sent to the forward or reverse ports.
- Forward: Pressurized hydraulic fluid is sent to the forward piston within the clutch via the forward port. A pressure regulating valve allows some fluid to continue to flow through the lubricating port.
- Reverse: Pressurized hydraulic fluid is sent to the reverse piston within the clutch via the reverse port. A pressure regulating valve allows some fluid to continue to flow through the lubricating port.

The clutch peddle actuates what is called the inching rod. The inching rod is a modulating type valve which, as the clutch pedal is pressed, opens a bypass port and allows the hydraulic pressure going to either the forward or reverse ports to escape back to the lubrication port. When its completely pressed and the inching rod is pulled all the way out (open) the hydraulic pressure is routed completely to the lubricating port.


For purposes of diagnosing the dragging clutch on my tractor its important to understand that the Ever Clutch is only engaged by hydraulic pressure. This means that with the engine off the rear wheels are free to rotate even with the gearbox in gear. This leads us to a simple test as pointed out by Dick on this forum: by jacking up 1 rear wheel (open differential) with the engine off and the parking brake not engaged, that wheel should be free to rotate with the gear box engaged.
- This was done on my tractor and resulted with the wheel being difficult to turn when in gear (not impossible, but difficult). And alternatively, easy to rotate with the gearbox out of gear.
- Also, with the engine running and the clutch or Shuttle shift in neutral the raised rear wheel spins in reverse.

This tells me that the dragging clutch is not a problem with the hydraulic control unit, but rather a mechanical problem inside of the Ever Clutch itself. Having studied the schematics of the ever clutch, I can only see two mechanical reasons that the clutch wont disengage.
1) The spring that keeps the engaging piston off of the clutch packs has broken causing the clutch pack to remain in gear.
2) The piston itself has seized or is somehow stuck and cant travel away from the clutch packs.

...

 

[rbargeron]

My L3650 with a wet clutch just stopped moving. The engine runs, all hydraulics work, all the gear shift and clutch pedal feels normal but nothing moves when the clutch is released. Obviously something came loose in the internal drive.......

Same in high and low speed ranges? Did the tractor stop while moving along? Any noises? Does the pto turn when engaged?

 

[ldozier]

The mechanic got it apart and found the input power driveline had stripped the splines.. anybody know where to get a replacement shaft?

 

[SidecarFlip]

Kubota factory parts.

 

[North Idaho Wolfman]

If it's the part that connects to the flywheel via splines, P/N 35080-14220, I don't have good news, that part is obsolete.

You could try West kentucky tractor parts for a used one, but your odds are low.

I don't know of a work around for it either.

Post a picture of the part if you would.

 

[ldozier]

If it's the part that connects to the flywheel via splines, P/N 35080-14220, I don't have good news, that part is obsolete.

You could try West kentucky tractor parts for a used one, but your odds are low.

I don't know of a work around for it either.

Post a picture of the part if you would.

Kubota told me no shafts were available however they had a few of the complete clutch packs available for nearliy $5000 which included the shaft and the flywheel insert. Add a few gaskets and tax, about $6000. No apologies. noteven a dealer discount from corporate or the local dealer. I needed a tractor so I bought a used MX4700 with 850 hours while the search for parts was ongoing. My mistake. Now it needs fuel injector work at 1950 hours. No more kubotas At my house.

 

[North Idaho Wolfman]

Kubota told me no shafts were available however they had a few of the complete clutch packs available for nearliy $5000 which included the shaft and the flywheel insert. Add a few gaskets and tax, about $6000. No apologies. noteven a dealer discount from corporate or the local dealer. I needed a tractor so I bought a used MX4700 with 850 hours while the search for parts was ongoing. My mistake. Now it needs fuel injector work at 1950 hours. No more kubotas At my house.

Yes parts for 30 year old tractors that were only made in a very limited amount (WET) and are obsolete are expensive.

Now as Far as the MX4700
I hate to tell you, it's semi normal, for diesels to have these kinds of issues.
It has nothing to do with the tractor or the design, It's just one of those things that happen.
It's nothing super expensive or hard to fix.
All it take is one little particle of debri to get past the filter to cause it.