Looking for advice on rear remotes setup for L3902...

ErikTurner

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Hello,
I'm buying a new Kubota L3902 and I want to set it up to be able to use common implements with remotes.
I am adding the 3rd function to be able to eventually use a grapple, but I need some advice on the rear remote valve types to use, and whether this setup makes sense to do. This is my first real tractor, and I'm trying to make it be flexible to use implements I find at auctions. (I'm aware I have to be careful to get implements that can operate on the limited pressure a 3902 can output).

The sales guy at the Kubota dealership near me doesn't know much about remotes and is not helpful with regard to them. I guess people around here tend to buy stock tractors with no remote upgrades.

Here's what I am planning:
3rd function up front for grapple or whatever
3 factory remotes in the back, two with float detent for top n tilt hydraulic toplink and sidelink, and a free one for general use hooked to an expander, 3rd RR valve with ??? valve.
Hydraulic port expander (hooked up to the free factory remote) to provide more ports for whatever other implements need them.

What type of valve should go on the expander port? I'm thinking a detent valve so it can be locked open, but I don't know if it makes more sense to use self cancelling or non self cancelling, float detent, or spring center. Spring center probably irritating if it moves back to center, and I can't imagine using float with the log splitter, but it might be nice on the flail to float along the ditch.

From auctions, I already have a log splitter (1 remote) and an offset ditch bank flail mower (2 remotes), and the other 2 are taken up by top n tilt, so I will need to do something to add at least 1 more port for the flail. I think the Summit Hydraulics expanders look good, but I'm not sure if I should add 2, 3, or 4 ports to support whatever later. The cost isn't that different amongst those. I also have several other PTO driven attachments.

Advice would be appreciated, How would you configure a general purpose tractor with remotes to handle the above options?
Erik
 
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PaulL

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Hmm. Sounds like too many ports to me. You only use one of those implements at a time - so you only need as many ports as the single implement with the most functions. Three would be the most I could imagine, but probably two is plenty. Plus the third function.

I'd also note that third functions cost about the same to install now as they do to install when you get the grapple. But grapples all come with different connectors, and your needs may change. Personally I'd get the third function when I needed it, and have my dealer set up the grapple and third function together.
 

TheOldHokie

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Hello,
I'm buying a new Kubota L3902 and I want to set it up to be able to use common implements with remotes.
I am adding the 3rd function to be able to eventually use a grapple, but I need some advice on the rear remote valve types to use, and whether this setup makes sense to do. This is my first real tractor, and I'm trying to make it be flexible to use implements I find at auctions. (I'm aware I have to be careful to get implements that can operate on the limited pressure a 3902 can output).

The sales guy at the Kubota dealership near me doesn't know much about remotes and is not helpful with regard to them. I guess people around here tend to buy stock tractors with no remote upgrades.

Here's what I am planning:
3rd function up front for grapple or whatever
3 factory remotes in the back, two with float detent for top n tilt hydraulic toplink and sidelink, and a free one for general use hooked to an expander, 3rd valve with ??? valve.
Hydraulic port expander (hooked up to the free factory remote) to provide more ports for whatever other implements need them.

What type of valve should go on the expander port? I'm thinking a detent valve so it can be locked open, but I don't know if it makes more sense to use self cancelling or non self cancelling, float detent, or spring center. Spring center probably irritating if it moves back to center, and I can't imagine using float with the log splitter, but it might be nice on the flail to float along the ditch.

From auctions, I already have a log splitter (1 remote) and an offset ditch bank flail mower (2 remotes), and the other 2 are taken up by top n tilt, so I will need to do something to add at least 1 more port for the flail. I think the Summit Hydraulics expanders look good, but I'm not sure if I should add 2, 3, or 4 ports to support whatever later. The cost isn't that different amongst those. I also have several other PTO driven attachments.

Advice would be appreciated, How would you configure a general purpose tractor with remotes to handle the above options?
Erik
Your experience with the dealers lack of knowledge seems to be pretty common. I went through the same situation last year with my L3901 before giving up on the dealer.

I would suggest three OEM remotes with float on at least two. Float on the third wont hurt anything other than your wallet but may be of marginal value.

You do not need an expander to add more valves to the OEM stack. Simply plumb them into the circuit either before or after the stack.

Outlets for a log splitter need to be constant flow and dont require a directional control valve. They are easy to plumb off the power beyond for the OEM remotes.

Personally I think the outlets provided with the Kubota valves are pretty chintzy. Here is the custom panel I made for the back of my L3901. It has four sets of outlets mounted and room for two more if ever needed. The outlets on the left are constant flow for the log splitter and controlled by a simple selector valve mounted next to the PTO lever.

Dan

20210922_082419.jpg


20210926_125022.jpg
 
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Impala

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L3302 prior B2601, prior BX2230
Jan 16, 2021
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Hmm. Sounds like too many ports to me. You only use one of those implements at a time - so you only need as many ports as the single implement with the most functions. Three would be the most I could imagine, but probably two is plenty. Plus the third function.

I'd also note that third functions cost about the same to install now as they do to install when you get the grapple. But grapples all come with different connectors, and your needs may change. Personally I'd get the third function when I needed it, and have my dealer set up the grapple and third function together.
As far as the 3rd function my dealer doesn't charge labor on a new tractor so it was easier to have it set up right away for the grapple, plus no additional trip to the dealer. The connectors are no big deal they should match them to the 3rd function for you. I upgraded my tractor and the dealer gave me the new connectors to swap the grapple they had previously sold me over. Easy peasy.
 

ErikTurner

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Hmn, thanks for the advice! It really helps. That is a sweet custom mounting panel Dan! @TheOldHokie I'd like to end up with something clean like that.

@PaulL I think I need a minimum of 4 rear ports for my implements.... the hydraulic top link and hydraulic side link will be set up all the time, using up two, and the offset ditch bank flail mower requires 2 more ports. Probably I want to have 5 or 6 ports on the back.... two on the TopNTilt, 1 constant flow for the log splitter when its used, 2 for the flail, and the possibility of having another one if I find an implement that needs 3. Although, the only individual implements I know of that need that many are batwing mowers and I don't need one of those ever.

I guess I could get a long cable and run the second flail port from the 3rd function up front, but I'd rather have clean ports in the back and the grapple available up front... Maybe I'm being lazy by expecting to not have to swap out the hydraulic links or re-route from the front to use other implements.

The flail controls don't need to be operated at the same time really, I expect usually you wouldn't be swinging it in and out very often while mowing, and probably not changing the angle very often either, so an expander with a selector would work OK for that and let me use the OEM control lever to control it. Or would it make more sense to add some additional aftermarket control levers bolted somewhere and plumb extra actual valves? I'm sure adding actual valves and more control levers is more cost than an expander though.

@TheOldHokie > Simply plumb them into the circuit either before or after the stack. ... Hmn.. I'm going to have to do more research into how these things are set up... I am a noob.

For the log splitter will it work if I plug it into a regular lever-controlled valve and open it all the way, or does it have to be set up directly plumbed?

@Impala Yeah, they don't charge labor when the upgrades are part of the initial purchase, and I'd rather not have to have them tear things apart to upgrade it later. I already own a grapple I found at auction for cheap, so I'm ready for the 3rd function up front now.

I'm going to do more research into hydraulics, as I guess this setup is more complicated than what folks usually attempt.
 

PaulL

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I must be missing something. Surely you'd unplug the top and tilt when you had the flail on, and use those ports for the flail? I guess you could leave the top and tilt cylinders plugged in and use different ports for the flail, but that means you're looking for a lot of levers on the operator station.
 

TheOldHokie

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Hmn, thanks for the advice! It really helps. That is a sweet custom mounting panel Dan! @TheOldHokie I'd like to end up with something clean like that.

@PaulL I think I need a minimum of 4 rear ports for my implements.... the hydraulic top link and hydraulic side link will be set up all the time, using up two, and the offset ditch bank flail mower requires 2 more ports. Probably I want to have 5 or 6 ports on the back.... two on the TopNTilt, 1 constant flow for the log splitter when its used, 2 for the flail, and the possibility of having another one if I find an implement that needs 3. Although, the only individual implements I know of that need that many are batwing mowers and I don't need one of those ever.

I guess I could get a long cable and run the second flail port from the 3rd function up front, but I'd rather have clean ports in the back and the grapple available up front... Maybe I'm being lazy by expecting to not have to swap out the hydraulic links or re-route from the front to use other implements.

The flail controls don't need to be operated at the same time really, I expect usually you wouldn't be swinging it in and out very often while mowing, and probably not changing the angle very often either, so an expander with a selector would work OK for that and let me use the OEM control lever to control it. Or would it make more sense to add some additional aftermarket control levers bolted somewhere and plumb extra actual valves? I'm sure adding actual valves and more control levers is more cost than an expander though.

@TheOldHokie > Simply plumb them into the circuit either before or after the stack. ... Hmn.. I'm going to have to do more research into how these things are set up... I am a noob.

For the log splitter will it work if I plug it into a regular lever-controlled valve and open it all the way, or does it have to be set up directly plumbed?

@Impala Yeah, they don't charge labor when the upgrades are part of the initial purchase, and I'd rather not have to have them tear things apart to upgrade it later. I already own a grapple I found at auction for cheap, so I'm ready for the 3rd function up front now.

I'm going to do more research into hydraulics, as I guess this setup is more complicated than what folks usually attempt.
Your setup is not at all complicated. It just involves more valves than usual. I have plenty of those outlet panels but it may not work with the OEM hoses and couplers.

Assuming the L02 is the same as the L01 the factory remotes are a three valve stack bolted to the side of the hydraulic top cover. They are fed by a hose coming off the power beyond on your loader and return to the hydraulic outlet under the front floor board. It is cheap and easy to insert a two or three spool valve in the middle of that loop.

Feeding the log splitter off a directional control valve is a poor idea. Plumb it into the power beyond loop like any other valve. You can get fancy with a selector valve and a couple outlets or go cheap with just a male/female quick connect in the hose loop. The latter is exactly how Kubota connects their backhoes.

By far the cheapest and most effective way to add additional remotes is with an additional control valve inserted into the power beyond loop. Two additional spools is maybe $300 including all of the plumbing and outlets.

Dan
 
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MtnViewRanch

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I have a question. If the OP adds an additional 2-3 spool valves, where is he suppose to mount them for ergonomic use?
It looks like Kubota has dropped the float featured valves as an option on the economy tractors, No longer available on the std L models or the MX models. :(

Something else to consider, the factory rear remote valves of every open center Kubota hydraulic system currently sold should be considered a risk for excessive internal valve leakage. ( cylinders drift excessively) Note that Kubota will not warranty this issue, "just how it is" is the fix Kubota corporate issues.

If it were me and this is simply my opinion with how things currently are, based on what your current needs are.
I would put a 3rd party 5 valve set up on the tractor, 4 valves with the float feature, and 1 detent valve. This covers every situation that you have. The trick is to not get 3rd party valves that have the same issues that the factory valves have which seem to be quite common. :cautious:

Then of course you have the time to figure out and fabricate the ideal valve mount & location for 5 valves and the couplers.

All things to consider.


On my Mahindra 3215 which is the same physical size machine as the 3902, there is only a single factory rear remote available, I installed a stack of 3 Bosch cast iron diverters so that I have 4 sets of couplers to use all with a single lever with a 3 switch control grip on the lever.

This has worked out well for me, :cool: but there are times when I think that I might prefer 4 separate valves and levers. :unsure:
 

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TheOldHokie

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I have a question. If the OP adds an additional 2-3 spool valves, where is he suppose to mount them for ergonomic use?
It looks like Kubota has dropped the float featured valves as an option on the economy tractors, No longer available on the std L models or the MX models. :(

Something else to consider, the factory rear remote valves of every open center Kubota hydraulic system currently sold should be considered a risk for excessive internal valve leakage. ( cylinders drift excessively) Note that Kubota will not warranty this issue, "just how it is" is the fix Kubota corporate issues.

If it were me and this is simply my opinion with how things currently are, based on what your current needs are.
I would put a 3rd party 5 valve set up on the tractor, 4 valves with the float feature, and 1 detent valve. This covers every situation that you have. The trick is to not get 3rd party valves that have the same issues that the factory valves have which seem to be quite common. :cautious:

Then of course you have the time to figure out and fabricate the ideal valve mount & location for 5 valves and the couplers.

All things to consider.


On my Mahindra 3215 which is the same physical size machine as the 3902, there is only a single factory rear remote available, I installed a stack of 3 Bosch cast iron diverters so that I have 4 sets of couplers to use all with a single lever with a 3 switch control grip on the lever.

This has worked out well for me, :cool: but there are times when I think that I might prefer 4 separate valves and levers. :unsure:
I cannot comment on leakage issues with the OEM valves. You have made that point before. They are however a very neat ergonomic addition to the operator's station.

Its news to me that they no longer offer float on the L02 remotes but that is indeed what Build Your Kubota is showing. Only rear remote valve options on an L3302/L3902 are spring center, locking detent, and self canceling detent. Float detent is still available on all of the L01s. Makes me wonder if they have changed the base mounting kit on the L02 to something more like the Grand L and they have clearance issues. KPAD isn't showing anything helpful on the L02 parts breakdowns.

Unless I am missing something you can't do simultaneous float on multiple sets of outlets using a pure diverter solution.

An aftermarket 5 valve stack is going to be the most versatile and least expensive solution. You have lots of valve options but you lose the ergonomics of the OEM installation. A Bucher 12 GPM stack valve with four float sections and one spring center section costs around $900. Its also over 9" wide. Prince SV is even bigger.

I think I have the outlet mounting situation pretty well covered :unsure:

Dan
 

MtnViewRanch

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I cannot comment on leakage issues with the OEM valves. You have made that point before. They are however a very neat ergonomic addition to the operator's station.

Its news to me that they no longer offer float on the L02 remotes but that is indeed what Build Your Kubota is showing. Only rear remote valve options on an L3302/L3902 are spring center, locking detent, and self canceling detent. Float detent is still available on all of the L01s. Makes me wonder if they have changed the base mounting kit on the L02 to something more like the Grand L and they have clearance issues. KPAD isn't showing anything helpful on the L02 parts breakdowns.

Unless I am missing something you can't do simultaneous float on multiple sets of outlets using a pure diverter solution.

An aftermarket 5 valve stack is going to be the most versatile and least expensive solution. You have lots of valve options but you lose the ergonomics of the OEM installation. A Bucher 12 GPM stack valve with four float sections and one spring center section costs around $900. Its also over 9" wide. Prince SV is even bigger.

I think I have the outlet mounting situation pretty well covered :unsure:

Dan
The factory valve mounting is in an excellent location. The control lever placement leaves something to be desired in my opinion and their coupler mounting is even worse with the same mount being used in several different locations depending on if you have a backhoe and if you purchased some place other than the USA.

I have seen the same coupler mount situated at least 4 different ways.

Your coupler outlet is excellent (y)(y) other than it will not work for those with a backhoe. 😞

Kubota has changed valve options on a lot of their models, it is not just the L02s.

As far as float on multiple diverters, typically that would be correct, but if you had maintained switches you could have all the ports in float, but why?

As far as the Kubota valve thing, I brought it up for the OP to know about.
Remember, I deal with this pretty much every single day and end up providing some sort of solution for these people that have purchased my T&T cylinders.
This is not a once in awhile issue, it is more common than not. 😞
 
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TheOldHokie

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The factory valve mounting is in an excellent location. The control lever placement leaves something to be desired in my opinion and their coupler mounting is even worse with the same mount being used in several different locations depending on if you have a backhoe and if you purchased some place other than the USA.

I have seen the same coupler mount situated at least 4 different ways.

Your coupler outlet is excellent (y)(y) other than it will not work for those with a backhoe. 😞

Kubota has changed valve options on a lot of their models, it is not just the L02s.

As far as float on multiple diverters, typically that would be correct, but if you had maintained switches you could have all the ports in float, but why?

As far as the Kubota valve thing, I brought it up for the OP to know about.
Remember, I deal with this pretty much every single day and end up providing some sort of solution for these people that have purchased my T&T cylinders.
This is rds not a once in awhile issue, it is more common than not. 😞
I dint doubt your assessment of the leakage issues with the OEM valves. Kubota seems to have a problem across the board in that regard.

They also seem to be moving backwards rather than forwards with the remotes on standard L's. I need to get back to that project. Have you seen the L02 version and if so is it the same as the L01?

Dan
 

TheOldHokie

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I have not seen any new tractors in person, from the pictures I would guess that the lever location will be the same positioning. :unsure:
I am talking about the way they mount the valve sections. The standard L's have used an adapter block and hoses that is more afterthought than OEM design.....

Dan
 

MtnViewRanch

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I would guess that they have not changed how the valves are mounted and plumbed.

But without actually seeing them or doing more research, we just won't know for awhile.
 

minthral

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I agree with others... too many valves. Problem stems from you thinking that top and tilt will always be connected.

Question though... do you have top and tilt cylinders and have you used it? For one, there is no factory top and tilt kit for that tractor. You can easily find a top cylinder that works for ~$300. Side link is more difficult to find as is 1) not commonly used for this series 2) out of stock and manufacturers are making other stuff instead. It can be found with lots of digging though and knowing technical details.

If you're using an offset flail mower, you don't need top or tilt at all. You just need to use normal top and side link that came with the tractor. This is an easy straight forward install. Or depending on your aftermarket (because kubota doesn't have the option) cylinders, they might have check valves, meaning they will lock in place so you just disconnect the hose after setting it in position and it wont move. BTW, you DONT want float for side OR toplink... you want check valves otherwise your hitch will wonder everywhere.

Top and tilt is for things like box or rear blade. You side tilt to change the grade or top tilt to dump/ adjust blade angle. It can be useful for a rotary or other cutter as well. It's not necessary for every single attachment. You need 3 remotes for a boom mower, but this tractor isn't big and heavy enough for that. Pretty much everything else requires only 2.

Also have you tried a tractor attached log splitter? They don't work well as the flow of the tractor is too low. For the same or little bit more money you can get a much better dedicated log splitter and then the logistics of having a stationary splitter as the tractor loader brings/lifts logs to it just works better than kneeling to the rear of the tractor and pushing levers to split wood. Also you aren't adding unnecessary hours to the tractor.

There are use cases for ~4 remotes on large tractors, but I honestly don't think there is a practical use case for more than 2 (or maybe 3) on this tractor. I'd recommend to get the factory kit with 2 remotes - 1 normal, 1 float. Then see how it goes...personal experience with that tractor is the factory levers are a good location, where you can comfortably steer with left hand and use right hand (wrapped around back of seat) to operate them while looking back at the implement from the right side...some other aftermarket setups would be an ergonomic nightmare IMO.
 
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TheOldHokie

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Also have you tried a tractor attached log splitter? They don't work well as the flow of the tractor is too low.
Actually I have and in fact last year on this very tractor. The 6.8 GPM flow rate and regenerative splitter valve cycles my splitter as fast as I can comfortably load and split. I have been using this splitter for almost 30 years and still haven't come even close to wearing out a tractor splitting wood. Operating it is no different than a trailer mounted unit other than I don't have to fight with starting a recalcitrant gas engine.

Here's my tractor at work with splitter and "too many" valves.

YMMV

Dan

20220212_141739.jpg
 

ErikTurner

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@TheOldHokie I think Kubota's configurator page is buggy and incomplete still for the L3902... if you add a single valve it allows you to choose all four valve types, but if you add two or three it removes some types. Last week it didn't let you add RR valves at all, and other stuff has disappeared from the options since which are still on the L3901 and supposedly almost everything from the L3901 is compatible with L3902 and vice versa. The dealer I am talking to said that the configurator is still goofy for L3902 and not fully set up yet, even on the dealer side.

Anyway, I would love to buy one of your mounting plates from you. I showed your mounting plate pictures to the dealer and they said they were willing to set it all up and support it assuming their hydraulic guy agrees. (And I have to settle on exactly which valve types to use and figure out what to do for the extra levers needed)...It's a really clean and protected setup. And the dealer said that the main reason they don't like to add more than 3 valves is that they don't know how to mount them without somebody fabricating something.

I am a bit concerned about the problem noted about leaky valves. On the other hand, I'm not wild about installing the hydraulics myself.

It seems like there are differing opinions on which valves to use for what tools. My understanding is that a float would be fine for both top n tilts, because you simply would not push over the detent to float unless you want to float for smoothing on top link, or float for riding the contour with sidelink...Am I missing something? @MtnViewRanch you recommended 4 floats and a detent... what implements would the detent (or self cancelling detent) be used with?

I was planning to leave the top and tilt on there all the time being lazy... I know that top and tilt isn't actively used for other implements, but I have collected several various attachments and my goal is to be able to easily switch between all the implements I have with minimum hassle and minimum time to reconfigure....this tractor is mostly just going to be maintaining my property, and maybe expanding to some neighbors. I *could* unhook the TNT I guess, but that's counter to the goal of it being minimal hassle to switch tools.

I have been collecting attachments from auctions for a year or two while figuring out what tractor to buy (debating between L3901/2 and GL4060, but 4060 is a lot bigger than makes sense for my property so I settled on L3902), most of them for awesome cheap deals:
a 66" rock rake grapple (probably a little big for this tractor, but should be ok for blackberries) (3rd function)
a 60" RCR1560 PTO rotary cutter (a little beat up but was only $150!)
a 50" wide /72" offset ditch bank flail mower (PTO +2 remotes)
a log splitter (1 remote)
a 30-50hp PTO wood chipper
a 72" rear blade
a RTA1250 PTO 4' rototiller

I plan to get eventually a heavy duty box blade, when I find a good deal on one, or if I don't like fixing my driveway with just the rear blade. My current belt driven garden tractor with a sleeve hitch sucks at grading my steep hilly driveway because the belt stretches immediately, among other deficiencies. And I probably want a lighter root rake grapple, but the grapple I got should be OK to start with, and it was cheap. My neighborhood has about 2 miles of private mostly gravel road we have to maintain, and I plan to learn how to touch it up so we don't have to pay so much for maintenance all the time and more money can go towards repaving the steep parts that were paved when it was a logging road like 40 years ago and are due for replacement. Oh, and I'll probably try to find a plow at some point too.. I have about an acre set aside for a garden currently.

@minthral I haven't bought the tractor yet, trying to work out the details of how to set up the hydraulics to be flexible for a wide variety of implements and switch jobs with minimal hassle.

For each of the valve types what implements use them optimally? This is my understanding so far:
SPRING CENTER VALVE SECTION
Seems like having the lever go back to center all the time would be annoying on most rear implements...what rear implements would you even want this on?
FLOAT DETENT VALVE SECTION
This one's good for when you want to have the option to let off all the pressure and let the implement ride on the ground, but allows you to have up or down pressure as needed.
SELF CANCELLING DETENT VALVE SECTION
For locking the control on at full pressure, and also having a safety release for if it is deadheading. Not sure what implements this would be good for, and the safety could be irritating.
DETENT VALVE SECTION
For locking the control on at full pressure, but with no safety relief function.
Not sure what implements this would be good for, and the lack of safety could let you overload your machine.
CONSTANT FLOW
For Backhoe, log splitter

Based on this, and my above implements, seems like most of them would want or at least not be hindered by floats aside from the log splitter? Seems like I could take a different flavor valve on the 5th one to support other specific tools if I know what/why the different one is good for.
 
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TheOldHokie

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@TheOldHokie I think Kubota's configurator page is buggy and incomplete still for the L3902... if you add a single valve it allows you to choose all four valve types, but if you add two or three it removes some types. Last week it didn't let you add RR valves at all, and other stuff has disappeared from the options since which are still on the L3901 and supposedly almost everything from the L3901 is compatible with L3902 and vice versa. The dealer I am talking to said that the configurator is still goofy for L3902 and not fully set up yet, even on the dealer side.

Anyway, I would love to buy one of your mounting plates from you. I showed your mounting plate pictures to the dealer and they said they were willing to set it all up and support it assuming their hydraulic guy agrees. (And I have to settle on exactly which valve types to use and figure out what to do for the extra levers needed)...It's a really clean and protected setup. And the dealer said that the main reason they don't like to add more than 3 valves is that they don't know how to mount them without somebody fabricating something.

I am a bit concerned about the problem noted about leaky valves. On the other hand, I'm not wild about installing the hydraulics myself.

It seems like there are differing opinions on which valves to use for what tools. My understanding is that a float would be fine for both top n tilts, because you simply would not push over the detent to float unless you want to float for smoothing on top link, or float for riding the contour with sidelink...Am I missing something? @MtnViewRanch you recommended 4 floats and a detent... what implements would the detent (or self cancelling detent) be used with?

I was planning to leave the top and tilt on there all the time being lazy... I know that top and tilt isn't actively used for other implements, but I have collected several various attachments and my goal is to be able to easily switch between all the implements I have with minimum hassle and minimum time to reconfigure....this tractor is mostly just going to be maintaining my property, and maybe expanding to some neighbors. I *could* unhook the TNT I guess, but that's counter to the goal of it being minimal hassle to switch tools.

I have been collecting attachments from auctions for a year or two while figuring out what tractor to buy (debating between L3901/2 and GL4060, but 4060 is a lot bigger than makes sense for my property so I settled on L3902), most of them for awesome cheap deals:
a 66" rock rake grapple (probably a little big for this tractor, but should be ok for blackberries) (3rd function)
a 60" RCR1560 PTO rotary cutter (a little beat up but was only $150!)
a 50" wide /72" offset ditch bank flail mower (PTO +2 remotes)
a log splitter (1 remote)
a 30-50hp PTO wood chipper
a 72" rear blade
a RTA1250 PTO 4' rototiller

I plan to get eventually a heavy duty box blade, when I find a good deal on one, or if I don't like fixing my driveway with just the rear blade. My current belt driven garden tractor with a sleeve hitch sucks at grading my steep hilly driveway because the belt stretches immediately, among other deficiencies. And I probably want a lighter root rake grapple, but the grapple I got should be OK to start with, and it was cheap. My neighborhood has about 2 miles of private mostly gravel road we have to maintain, and I plan to learn how to touch it up so we don't have to pay so much for maintenance all the time and more money can go towards repaving the steep parts that were paved when it was a logging road like 40 years ago and are due for replacement. Oh, and I'll probably try to find a plow at some point too.. I have about an acre set aside for a garden currently.

@minthral I haven't bought the tractor yet, trying to work out the details of how to set up the hydraulics to be flexible for a wide variety of implements and switch jobs with minimal hassle.

For each of the valve types what implements use them optimally? This is my understanding so far:
SPRING CENTER VALVE SECTION
Seems like having the lever go back to center all the time would be annoying on most rear implements...what rear implements would you even want this on?
FLOAT DETENT VALVE SECTION
This one's good for when you want to have the option to let off all the pressure and let the implement ride on the ground, but allows you to have up or down pressure as needed.
SELF CANCELLING DETENT VALVE SECTION
For locking the control on at full pressure, and also having a safety release for if it is deadheading. Not sure what implements this would be good for, and the safety could be irritating.
DETENT VALVE SECTION
For locking the control on at full pressure, but with no safety relief function.
Not sure what implements this would be good for, and the lack of safety could let you overload your machine.
CONSTANT FLOW
For Backhoe, log splitter

Based on this, and my above implements, seems like most of them would want or at least not be hindered by floats aside from the log splitter? Seems like I could take a different flavor valve on the 5th one to support other specific tools if I know what/why the different one is good for.
You have a small misconception of how the various options work.

  1. Spring Center - this is standard operating mode typically used for controlling DA cylinders. You have to hold the lever to keep the cylinder moving and it automaticakly returns to neutral when you release it.
  2. Locking Detent - this valve stays in the shifted position until you manually return it to neutral. Commonly used to control devices like a hydraulic motor that need continuous flow to run. It could be used for a log splitter but cascading valves is a poor design.
  3. Self Canceling Detent - similar to a locking detent except that it spring centers as soon as the actuator stalls and pressure hits a predetermined kickout pressure. It is a convenience not a safety feature and useful when you want to start a cylinder in one direction and then remove your hand for other uses while the cylinder continues to travel. The valve automatucally returns to neutral and travel stops when the cylinder hits end of travel. The retract operation on a log splitter valve commonly has a self canceling detent.
  4. Locking Float Detent - same as spring centering except the valve has a fourth locking position where pump and both work ports are open to tank. This unloads the cylinders and allows the rod to move freely in and out. The valve has to be manually shifted out of float. This feature is useful for allowing the implement to follow the ground countours.
I agree with your assessment of top and tilt. I have a hydraulic top link on my tractor. I am not going to just unplug it to use those ports for another valve on a 3pt hitch device. If I unplug it the top link is also coming off. The same would be true of the side link. When they are on the tractor I want them plugged in so they can be adjusted.

Your Kubota guy is not going to want to deal with my panel. The factory hoses and couplers are not going to work with it. You would need new custom hoses and oanel mount couplers. That is hundreds of dollars in wasted parts and why I decided against purchasing the OEM kits when I bought my L3901. If you were goung that route the outlets from a Grand L would be a wonderful upgrade. Unfortunately Kubota wants $100 each for the coupler supports plus another $100 plus for each coupler. Cloning them is on my To-Do list as a possible replacement for the panel and a way of accommodating machines with backhoes.

Dan
 
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MtnViewRanch

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Oct 10, 2012
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One additional note for clarification on the Spring Center valve. When in the spring back-center-neutral position, the valve is closed and the rod is supposed to stay set at the position that it was left in.
This has to be the most common control valve there is and is typically used for almost every implement cylinder there is.

The issues with the factory Kubota valves, all of the different types is that the rod does not stay in position. If you are lucky it will stay as adjusted for a reasonable amount of time. (does not hinder operation of the tractor with constant resetting of the hydraulic cylinder-s required)

You have a better chance of having a defective valve vs having an acceptable one.
This is simply the way that it currently is and should be known ahead of time so that a person understands that the valves are of poor quality and may very well need to be dealt with using other types of solutions.

Kubota Corporate will not warranty this issue, you get what you get.

I understand that most people choose to not fool with hydraulics and prefer to have the dealer deal with this stuff. We are simply attempting to inform you of what is available and what to expect.

Good luck with your decisions. :)
 

PaulL

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Jul 17, 2017
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Also have you tried a tractor attached log splitter? They don't work well as the flow of the tractor is too low. For the same or little bit more money you can get a much better dedicated log splitter and then the logistics of having a stationary splitter as the tractor loader brings/lifts logs to it just works better than kneeling to the rear of the tractor and pushing levers to split wood. Also you aren't adding unnecessary hours to the tractor.
This is excellent advice. Dad had a log splitter on his 100hp tractor (Kioti). It was excellent. But we had to lift all the rounds onto it by hand - we would have used the loader or forks for that if it wasn't tractor attached. On a smaller tractor......you'd be much better with a standalone splitter.