L2800HST PTO engagement noise

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
Soooo ,,, last week I was chipping branches and and realized the chipper wasn't turning the speed it should. Took off my ear muffs and could hear a loud clacking noise. UH-OH. Figured maybe the engagement cable was out of adjustment so went down to the shop and checked it. Nope engages right where it should. But I gave the adjustment a couple turns anyway. The clacking is less but still there. Now when I move the tractor i get the clacking noise even without the pto engaged. Almost like something is sliding back on a shaft and the dogs are trying to engage. I can stop it by pushing in the clutch.

I know what you are thinking.... over run clutch.... this is a different sound. And the over run clutch still is doing it's thing.

In the video you can hear it as I accelerate up to pto speed. This one wasn't too bad.

Any ideas on what I'm looking for?

 

old and tired

Well-known member

Equipment
L2800 HST
Dec 8, 2019
872
372
63
Raleigh, NC / Hillsville, Va
Don't know what it is but want to see what you find out... So you do have the ratcheting CAMs? (Model L2800 from 2004 to the early 2006 vintage) Wondering if the CAMS might just be worn out??

(reminds me that I need to buy a set of these CAMS before they don't make them any more....)
 
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Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
Don't know what it is but want to see what you find out... So you do the ratcheting CAM? (Model L2800 from 2004 to the early 2006 vintage) Wondering if the CAMS might just be worn out??

(reminds me that I need to buy a set of these CAMS before they don't make them any more....)

I hope the cams aren't worn out.... just turned 300 hours on the tractor.
 

old and tired

Well-known member

Equipment
L2800 HST
Dec 8, 2019
872
372
63
Raleigh, NC / Hillsville, Va
I had to get rid of a tiller because it would skip here and there while I was tilling... The first few cases of CAM problems were from commercial use of a tiller on our tractors.

But at 300 hours... that would be some serious chipping!?!?! ....To have a problem with the PTO CAMs

I could see a chipper being hard on a PTO... What model (or what size wood do you chip?)
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
3,686
805
113
Mid, South, USA
cams are probably worn. Similar to a motorcycle transmission, kinda like a dog ring style. When the dogs wear and get rounded, they will slip over each other quite easily. I did quite a few of them. The new ones are a different part number than the originals, so I don't know if they changed the supplier, the material, or the color or what. While you're in there, I'd suggest replacing the tension spring and snap ring too.

It's not terribly hard if you have any mechanical knowledge. As I remember the worst part is refilling the transmission with super UDT. I leave the loader on, backhoe and subframe have to come off if you have those. I support the front of the tractor with the loader frames, then split at the rear section (basically under the seat). When you get all the bolts out of the rear section, just roll the rear tires away. Leave it in neutral obviously. Use the roll bar to help you stabilize it. Once it's far enough away, just lay the roll bar down on the ground. Easy. It's easier than you think!
 

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
I had to get rid of a tiller because it would skip here and there while I was tilling... The first few cases of CAM problems were from commercial use of a tiller on our tractors.

But at 300 hours... that would be some serious chipping!?!?! ....To have a problem with the PTO CAMs

I could see a chipper being hard on a PTO... What model (or what size wood do you chip?)

Bush Hog CS100P. 90% of what I chip is pine branches up to 2". Ocasionally I'll go up to 3" but that is pretty rare.

Over that past 6 years I've probably used the 30 hours total.

I bought the tractor with 70 hours and it was only used for bush hogging a field by the previous owner.

The pto engagement cable broke last year and I replaced it flowing the instructions that came with it. The WSM was useless with the adjustment
 

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
cams are probably worn. Similar to a motorcycle transmission, kinda like a dog ring style. When the dogs wear and get rounded, they will slip over each other quite easily. I did quite a few of them. The new ones are a different part number than the originals, so I don't know if they changed the supplier, the material, or the color or what. While you're in there, I'd suggest replacing the tension spring and snap ring too.

It's not terribly hard if you have any mechanical knowledge. As I remember the worst part is refilling the transmission with super UDT. I leave the loader on, backhoe and subframe have to come off if you have those. I support the front of the tractor with the loader frames, then split at the rear section (basically under the seat). When you get all the bolts out of the rear section, just roll the rear tires away. Leave it in neutral obviously. Use the roll bar to help you stabilize it. Once it's far enough away, just lay the roll bar down on the ground. Easy. It's easier than you think!
Thanks for the info. I've split tractors before so it doesn't scare me. This just comes at a bad time for some work I had planned.

One thing that doesn't make sense to me though.... with the pto disengaged, if I ran the tractor up the hill in my driveway, it will sound like the cams are trying to engage. Like maybe the cams are freely sliding together. Is there a spring or something that holds them apart when disengaged?

When you say the worst part is refilling with Super UDT. I assume you are saying this because of cost?
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
3,686
805
113
Mid, South, USA
I suspected as much. Not a particularly hard job really. Done a few of them. I wish there was a better design. Actually come to think of it I think they changed the angle of the engagement dogs so that they kind of hold each other together better when engaged. IIRC it's not noticeable with the naked eye.
 

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
I suspected as much. Not a particularly hard job really. Done a few of them. I wish there was a better design. Actually come to think of it I think they changed the angle of the engagement dogs so that they kind of hold each other together better when engaged. IIRC it's not noticeable with the naked eye.
I have about 4 hours in tear down. Took off way more than I needed to but it provided better access. My original idea was to leave the hoe sub frame on and just disconnect from the loader frame. Then use that to rest on the dolly. But there was just not enough space for the "U" shape to clear the bottom of the loader posts. Probably less than 1/8".

Ordering parts this morning. You can see the engagement arm is worn also.
 
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Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
Parts are in. As Lugbolt mentioned they now have a negative angle to keep them from slipping. Hoping to get it back together this weekend.

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Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
What else besides the CAMS did you have to purchase... I need to buy a set to keep on hand.

I wonder if the old CAMS could have been machined with a new face?
Here is my parts list. The cam kit comes with the front and rear cams and the bolt to secure the front cam on the shaft. Parts 70, 100 and 130 on the diagram. To be safe I'm also changing the spring in front, 80.

The engagement arm, number
10 was worn so I replaced that also.

Orings for the suction tube and engagement arm just because I'd hate have to go back and do it after the system was full of fluid.

I'm at 400 hours so it was time for fluid and filter change. If I wasn't near at the fluid change I probably would have reused the fluid and just changed filters.

Screenshot_20211217-084842_Samsung Internet.jpg
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Screenshot_20211217-085452_Samsung Internet.jpg
 

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
I do believe that the cams could be reworked fairly easy. I may set them up in the mill one day see how they come out. I'd probably mill off the ramps and make them like the updated part.
 

old and tired

Well-known member

Equipment
L2800 HST
Dec 8, 2019
872
372
63
Raleigh, NC / Hillsville, Va
Thanks so much for that list...

About milling; I would want to keep the overriding ramps (to keep that feature). I guess I'm wondering with these new "locking" CAMS, when the mower momentum is faster than the engine (throttling down) where does the excess mower momentum get dissipated in to? Does it go through the PTO to the motor?

The forces from my chipper's flywheel (especially when I get off the tractor without flipping the seat up). I assume with these locking CAMS, that power has to push on the engine? Or is there an over riding feature in those tractors with the locking CAMS?

Anyone with one of these Standard L models should be able to tell us.... except for those with the over running “Ratcheting" CAMS...
 
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PoTreeBoy

Well-known member
Lifetime Member

Equipment
L35 Ford 3930
Mar 24, 2020
1,001
380
83
WestTn/NoMs
I've been following this just out of interest. Looks like Kubota did away with the overrunning clutch on the new parts. I don't see the need for it with HST - you can still control the tractor speed with the treadle.
By the lack of wear on the lower part of the coupling ramps, I'd say the old one wasn't fully engaging. Probably good you replaced the engagement arm.
 

Boatman

Active member

Equipment
Kubota L2800, Kubota BX1870
Nov 26, 2016
103
26
28
Mill Spring, NC, US
Thanks so much for that list...

About milling; I would want to keep the overriding ramps (to keep that feature). I guess I'm wondering with these new "locking" CAMS, when the mower momentum is faster than the engine (throttling down) where does the excess mower momentum get dissipated in to? Does it go through the PTO to the motor?

The forces from my chipper's flywheel (especially when I get off the tractor without flipping the seat up). I assume with these locking CAMS, that power has to push on the engine? Or is there an over riding feature in those tractors with the locking CAMS?

Anyone with one of these Standard L models should be able to tell us.... except for those with the over running “Ratcheting" CAMS...
I've run many tractors over the years and this is the only one that has had this type of over run slipper. Yes the implement, like a chipper or rotary cutter, will push the engine. But it's always been my practice to bring the engine rpm down slowly and disengage the pto as soon as I can. With the L2800HST it's even easier. I cut the throttle and push in the clutch at the same time. Then while the clutch is depressed I disengage the pto.