I recently purchased a new 2015 M59 and ordered the rear hydraulic remote kit and requested "locking flow" detent to allow me to run implements requiring constant flow like a hydraulic motor.
The dealer provided me with "locking float detent" and is saying that they are having a hard time finding a valve kit from Kubota to give me "locking flow".
As a work around I have to bunny cord the valve ON which is to wrong way to go and NOT what I ordered.
Has anybody else gone through this or can anyone provide me with the appropriate Kubota part number for the "locking flow" valve kit?
It sounds like your dealer confused his "locking float" and "locking flow". Easy enough to see how a mistake like that would happen. I can see where a flow lock would be a handy feature, but also sounds like it isn't going to happen without some work. If Kubota doesn't have that parts option there are a couple of ways to get it done.
1. You can always plumb one of the rear outlets to the hydraulic motor and hold the spool valve lever locked open with a bungy cord. Downside there has already been mentioned by an experienced M59 guy.....it works, but doesn't allow for much flow and puts lots of restriction on what flow gets through.So that trade off is a lower max flow and faster heat build up due to fluid friction. But it's certainly reasonable for part time use. Keep an eye on the fluid temp and it should be OK.
2. If the hydraulic motor needs more and cooler flow, you could accomplish what you want to do by using the type of spool valve that has a "power beyond" port. That port would then feed a manual or electrically actuated locking flow selector/diverter valve. The diverter allows you to switch between dumping unused flow directly back to the reservoir tank or going by way of the way of the hydraulic motor you want to run and then to the tank. Less friction than option number one so it ought to yield higher flow and less heat.
I don't know if the spool valve that comes in Kubota's kit for adding extra rear flow choices is the kind that has a PB port or not. Some valves do and others don't; but a look at a shop manual ought to tell that. If it doesn't, your dealer can simply choose a valve that does. Luckily our M59s are open center type hydraulic systems and so the spool valves are a type with a universal fit across various platforms. Any tractor mechanic with the valve in his hand can tell you if it is the kind with the PB option. The downside is this this 2nd option I'm outlining doesn't use 100% purely Kubota parts. And although it provides better flow than option #1, I'm betting it will still have less flow than the next option.
3. Option #3 works for those M59s that were ordered with the kit for the front remote hydraulic outlets. Page 63 in my much older ops manual. With that front system in place any mechanic can simply "Y" off of it and pipe the flow back to the rear of the tractor. Doing it that way will probably give you the best combination of max flow and max pressure.....but still without the locking flow feature that you wanted. And even the M59's max flow in that system is only 16 GPM although the pressure is 2800psi. Option 3 does have the bonus is that you already have both forward and reverse buttons controlling the direction of flow built right into the OEM loader control.
4. Another way to do it would be to drive an outboard hydraulic pump via the PTO shaft. There are lots of those PTO driven pumps on the market. Advantage here is you can plumb and valve it in any way you want, and it can potentially use full tractor PTO power to pump the
fluid. If the pressure demand doesn't change, using the PTO to drive a pump should add at the most (I'm making a slightly educated guess here) at most very roughly 50% to the rate you got with Option #3.
Good luck with it and let us know..
rScotty
