Jerky LSeries 3pt Hitch Fixed

[Leejohn]

Are you guys sure the Grand L valve well even bolt up? I looked at the parts list for the L2800, L3400, MX5000 and 3 GL's and what I see is that they well not. The only reason that L3010 came about was that I had a manual for it and posted the 3 adjustments that can be done or at least checked. Save alot of time taking apart many times.

 

[Harvest Moon]

You are all welcome and invited to double check but it's my understanding that the L3010 is the only "Grand" L with a compatible valve.

And originally the same valve was offered as part the draft control package on the L2800/L3400. After a while and I'm sure thousands of complaints, Kubota made the L3010 valve standard on the L2800/L3400. It had its' run, many people stuck with the original valve upgraded to it in the early days. As did I. It's much better, but not great.

The L3010 valve: 31351-39604

See it here: HarvestMoonL3400's Channel - YouTube and HarvestMoonL3400's Channel - YouTube
And the valve it replaced:HarvestMoonL3400's Channel - YouTube and HarvestMoonL3400's Channel - YouTube

For reasons unknown, after a while Kubota upgraded the valve again and more complaints started coming in about horrendous three point performance. At the time, it sounded to me like they chose to go backwards, as if the L3010 valve was performing too well. Check out Toy Camry's post from 2008, his is the upgraded valve that followed the L3010 valve:

Hi Everyone,

Just an update. My local dealer dropped off the tractor this morning and I must admit that I am confident he has tried his best to solve my problem. He just replaced my scratched valve with p/n YR90800102 (assembly control valve) and I have observed that my 3 point arms lift in closer to 1/4" increments than 1" increments so can I safely assume that the new "updated" valve is working as it should ?

When the tractor was being dropped off we did an informal test using a post hole auger mounted on the 3 point hitch and attached a 5 gallon pail of water to the auger gearbox. The Kubota sales representative raised and lowered the bucket of water as I recorded the video using his Blackberry. We performed the test using a John Deere 790 and then switched the auger to my L3400 and repeated the test.

Here's what the John Deere 790 looked like:

YouTube - John Deere 790 lifting with the 3 point hitch (3PH)

Here's what my repaired L3400 looks like:

YouTube - Kubota L3400 lifting with the 3 point hitch (3PH)

I agree, it does seem like Kubota is a huge corporation and we will have a difficult time getting the ear of their senior management but if (as a group) we are able to let them know of our dissatisfaction with the performance of our new tractors we may be able to get to the solution we are all looking for.

http://www.tractorbynet.com/forums/...800-position-control-jerky-6.html#post1535742


Good luck but there is no proven/published Grand L valve upgrade that will give you results like jokergerm's.

 

[crazyal]

Are you guys sure the Grand L valve well even bolt up? I looked at the parts list for the L2800, L3400, MX5000 and 3 GL's and what I see is that they well not. The only reason that L3010 came about was that I had a manual for it and posted the 3 adjustments that can be done or at least checked. Save alot of time taking apart many times.

I've got the parts break down for my 4240 and the valve would not work. I doubt you could get a dealer to just start picking valves off of his shelf and trying them out hoping that one will bolt up and work.

My guess is that the valve in the GL cost more because it's assembled with tighter tolerances. Some of the standard valves probably work just fine while others need to be set up better.

 

[teg]

1) Swapping the valve out for a Grand L valve will solve the problem. See Harvest Moon's post #192, 2 above... that's the best summery.

2) The existing valve could be tweaked by adjusting it by trial and error (time consuming process) I'm NOT convinced this is true, yet. I hope it is...

3) The hydraulic lines might be routed incorrectly - the factory return line coming off the steering gear is routed into the suction line just before it enters the pump. A revised metal tube assembly might correct this. Wasn't this for a different tractor altogether???

:dance1: I love seeing the water bucket videos :thumbsup:

 

[fenneran]

I am a fairly new Kubota owner (L2900), so I just went out and verified that mine is not jerky. I don't know if its ever been fixed or ever had this problem. Is the 2900 on the list of potential jerkiness? If so, I'd be glad to post a video if it would help.

 

[LD1]

Is the 2900 on the list of potential jerkiness? If so, I'd be glad to post a video if it would help.

NOPE.

As far as I know, it only effects the L2800 and L3400 and their sister tractors like the 3700, 3200, and 3800. The L2900 is an older model and a different valve with no know problems.

But thanks for the offer to help anyway.

 

[mjfox6]

You are all welcome and invited to double check but it's my understanding that the L3010 is the only "Grand" L with a compatible valve.

And originally the same valve was offered as part the draft control package on the L2800/L3400. After a while and I'm sure thousands of complaints, Kubota made the L3010 valve standard on the L2800/L3400. It had its' run, many people stuck with the original valve upgraded to it in the early days. As did I. It's much better, but not great.

The L3010 valve: 31351-39604

See it here: HarvestMoonL3400's Channel - YouTube and HarvestMoonL3400's Channel - YouTube
And the valve it replaced:HarvestMoonL3400's Channel - YouTube and HarvestMoonL3400's Channel - YouTube

For reasons unknown, after a while Kubota upgraded the valve again and more complaints started coming in about horrendous three point performance. At the time, it sounded to me like they chose to go backwards, as if the L3010 valve was performing too well. Check out Toy Camry's post from 2008, his is the upgraded valve that followed the L3010 valve:


http://www.tractorbynet.com/forums/...800-position-control-jerky-6.html#post1535742


Good luck but there is no proven/published Grand L valve upgrade that will give you results like jokergerm's.

I know they aren't supposed to be funny, but those water buckets splashing all over the place cracked me up!

My 2005 L3400 acts exactly the same as Harvest Moon's before and after videos. I had the valve swapped to the 3010 valve in 2005 under warranty. Much better than before, but still jumpy. The original was just plain unsafe, especially using a boom pole to skid logs.

I work with a guy that has a 2005 L2800. He had his valve swapped and is also the same as Harvest Moon's before and after videos.

 

[KennyV]

I am a fairly new Kubota owner (L2900), so I just went out and verified that mine is not jerky. I don't know if its ever been fixed or ever had this problem. Is the 2900 on the list of potential jerkiness? If so, I'd be glad to post a video if it would help.

Your L2900 is in the Grand L family... yours is included in the L2900, L3300, L3600 & L4200... KennyV

 

[Chilly807]

It sounds like I'm not much further ahead to swap the valve out of my 2009 L3400 for a 3010 valve..

I am going to investigate the air leak angle a bit further, after a couple hours running time last night mine definitely had air entrained in the oil from what I could see in the sight glass. As soon as the tractor shut down, it immediately disappeared, so the anti-foaming agents in the UDT are doing what they'rte supposed to. On starting it up again, after a few minutes the bubbles were visible again, although not to the same extent as before.

Sean

 

[Texas Fella]

Let it run for a while, lift the boxblade (or other implement) and push down on the box blade (try to bounce it). If there is too much air in the hydraulics, the air will compress, giving you a "spongy" felling, no air, the boxblade should hold firm.