Kubota 3rd Function Valve: Continuous Use OK?

[FatTire]

Hey, I posted on the hydraulics page, but looking for a little more response specifically from Kubota people. Is it OK to run an implement such as a hydraulic PHD continuously from the 3rd Function port using the Kubota factory set up? This came up because apparently some valves overheat when operated for even a few minutes at a time, including the one made by WR Long.

 

[Herkypilot]

I've installed two WR Long valves which are electric over hydraulic (diverter valves) and their directions specifically say not for continuous use as you describe. My understanding is the factory setup doesn't use a diverter valve, but a true third function. I know some Kubotas use sweepers on the front that run by hydraulic power, I'd think that is a factory setup. I'm sure others will chime in.

HP

 

[MHarryE]

I checked the manual for my M135GX loader and it does not state any limitation. It says to press the master button which will put the third function valve into the loader oil circuit (and an additional circuit that will generate heat). Then it states to press the upper rocker direction to flow oil out the a port and into the b port, or lower rocker button for oil out b and into a. It states oil will continue to flow as long as the button is depressed. It does not give a warning that anything will overheat if the circuit runs continuous flow. However, why do they add the master solenoid valves to control oil flow to the third function valve if there isn't a need? It would simplify the circuit and reduce cost if this electro/hydraulic section was not used. My L6060 did not come with a loader manual but it has the same control buttons as my M135GX. In heavy use my M135GX hydraulics run hotter than I would have permitted on the products for which I had design responsibility. I was concerned enough about hydraulic oil temperature to have an alert light and horn. I have measured temperatures well above the limit I used on my tractor - measured at the hydraulic oil filter and hydraulic pump. I would proceed with caution. The hydraulic oil cooler on my 4 Kubotas seem very small compared to those I used on my product. In one way that is fitting because my machines were 100% hydrostatic drives while my M135GX is primarily gear driven with hydraulic clutch pressure engagement, but my L6060, RTV900XT and GR2120 are all full hydro.

 

[MessickFarmEqu]

a PHD that you run in short bursts should be fine.

 

[LD1]

As long as the implement is rated for the full flow (GPM) of the tractor, there should be no issues using it continuous duty.

If you have a smaller implement, that has lower flow requirements, the ports and hoses could be a restriction and generate heat in the fluid.

 

[FatTire]

Guys, thanks for the responses. I am putting together a list of options in my head for a cab replacement for my MX5100 (2 remotes and a 3rd function), or if that doesn't come together, will install a 3rd function valve on the MX.

 

[Herkypilot]

There's no factory option for a 3rd function option on an MX5100. I used a WR long kit for a couple of years and it worked fine.

HP

 

[Luke'sScreenName]

There's no factory option for a 3rd function option on an MX5100. I used a WR long kit for a couple of years and it worked fine.

HP

It is dealer installed.

 

[Herkypilot]

It is dealer installed.

Just for clarity, it's not a Kubota option on the MX5100. I had an MX5100 and checked into it.

The WR Long install is pretty easy to DIY.

 

[Luke'sScreenName]

Just for clarity, it's not a Kubota option on the MX5100. I had an MX5100 and checked into it.

The WR Long install is pretty easy to DIY.

I think this may have changed... Just don't want to discourage someone from looking into it. There is a Kubota kit (made by LandPride). It is my understanding that it fits all of the MXs. :confused3: