Kubota L3650 hydraulics - adding remotes/etc.

[ishiboo]

I've been dealing with a TON of confusion regarding tractor/skid loader/post driver hydraulics, and I think I've come to a consensus but want to make sure. My L3650 has three hoses that go to the loader - essentially a power out port, a "power beyond" that goes to the 3 point hitch and then back to the pump, and then what I assume is the case drain. (The manual calls it out as "TANK PORT")

Given this setup, my understanding is the loader valve is "open center" and power flows through it to the 3 point valve, which is why the loader hose has to be connected in a "loop" to make everything continue to work.

I am putting a Shaver post driver on which has a single pressure hose, as well as a large case drain. The valve is an open center, but the return port is plugged. I believe I can put a return hose on the return port fitting, run the case drain to the hydraulic tank cap, and plug the post driver either directly to the tractor just as the loader is plugged in, or in series with the loader since both valve banks are open center. Is this correct?

I'm also confused then why adding remotes are so complex. Can I not just by my own open center valve, connect it in series with the loader and have all the auxiliaries I want? Why all this tapping in to lines in various places/etc. when people add remotes?

 

[ishiboo]

I confused myself a bit more... the hose with hte quick connect for "out" appears to connect to the "tank port" connection when the loader is not on, and NOT the "in" on the block. But the block has a screw which must be set to "O" when an implement is not attached. So I believe this means that the connections really don't matter when the loader is detached, and you have to turn the screw?

 

[J_J]

Your setup is similar to the hyd block on my B9200.

A tractor with open center hyd is no problem to connect other valves.

They simply connect in series and use the PB port or the hyd block to do this.

If you remove your loader, you will have to provide a jumper or plug the ports.

You probably have a PB port on your loader, and when connected, runs back to the hyd block, and then on to either a remote valve or the 3pt.

The Shaver OUT hose is a large hose, and it is recommended to go directly the tank through the fill cap.

If you are feeding the Shaver from any PB port, the Shaver post pounder could be considered the last valve in an open center hyd system and really does not need the Shaver PB port

So what you would do is not use the PB adapter and plug the PB port.

Now all fluid from the Shaver will exit the OUT port to tank.

If you need fluid for the 3pt, then you can use the PB adapter and run the PB OUT to the remote or the 3pt. The OUT port/hose will still go to tank.

You may have a relief valve on the hyd block, and that will become your main relief with the loader removed.

 

[ishiboo]

Your setup is similar to the hyd block on my B9200.

A tractor with open center hyd is no problem to connect other valves.

They simply connect in series and use the PB port or the hyd block to do this.

If you remove your loader, you will have to provide a jumper or plug the ports.

You probably have a PB port on your loader, and when connected, runs back to the hyd block, and then on to either a remote valve or the 3pt.

The Shaver OUT hose is a large hose, and it is recommended to go directly the tank through the fill cap.

If you are feeding the Shaver from any PB port, the Shaver post pounder could be considered the last valve in an open center hyd system and really does not need the Shaver PB port

So what you would do is not use the PB adapter and plug the PB port.

Now all fluid from the Shaver will exit the OUT port to tank.

If you need fluid for the 3pt, then you can use the PB adapter and run the PB OUT to the remote or the 3pt. The OUT port/hose will still go to tank.

You may have a relief valve on the hyd block, and that will become your main relief with the loader removed.

Thanks J_J, that pretty much confirms what I was thinking. The only thing I need to figure out tomorrow is if the Shaver valve (Glesen) can do power beyond. Apparently, the Prince valves some are machined for it and some are not... the manual for the V20 series shows my end cap (6770) can do it with simply the power beyond sleeve and does not list any exclusions/etc., so hopefully that's all it will take.

I can't wait to pound posts

 

[ishiboo]

Got everything plumbed out and pounded some posts today... have to say it works great! In case anyone is searching and wants to do this, it's a Shaver PD-10H post driver... same basic concept as the PD-8, PD12, etc. Hydraulic fittings/hoses/etc. add up quickly, and I think I'm probably about $300 in when all is said and done getting this working on my tractor. I paid $1500 for the driver with both 3 point and skid loader brackets, so for $1800 it's still a pretty good deal I think.

The tractor manual is correct with the hydraulic block diagram, but the loader fittings were NOT set up to do power beyond with a jumper... I think it's likely someone put the wrong fittings on the wrong connections, or it's always done with the screw control in the block.

The Glesen valve had a power beyond "kit" (a plug and two washers) which put a SAE #10 ORB on the side of the valve, Glesen/Parker part K-20-10-y for the #10 SAE or K-20-50-y for 1/2" NPT. Kubota in the early 90s used odd couplers, but the hoses and fittings were all 3/8" NPT. I removed the existing sets of couplers on the loader & tractor (since one was badly rusted, and a single Kubota poppet is the same price as a PAIR of 5675 couplers and the female is much more) and replaced with 3/8" ISO 5675 couplers. I ran two 1/2 hoses (since I cannot cheaply buy 3/8 in that length" to two more 5675 couplers from the post driver, so I hook it up in series with the loader and 3-point and have everything working at once.

The oil fill plugs on the transmission and rear housing are both 1" NPT, so I simply used a 1" NPT to hose barb adapter to connect to the 1" return hose off the post driver. This is low pressure, relatively high volume. I used clear vinyl to see what it is doing - if it doesn't hold up to the hydraulic fluid I'll replace it with some low pressure hydraulic hose. I also bought some ag quick connect hose connectors, however I am not sure if the rubber washer will hold up to hydraulic fluid so I haven't wasted them all yet as they're not cheap

Regarding the lack of speed from not having enough flow - the L3650 is only rated at 8GPM (or something). At IDLE, it is plenty fast for me to pleasurably drive posts. I am sure if I had 4000 of them to do I would want it faster, but I can't imagine at 1800 RPM it would be too slow for anyone. I can put a 4" round post in dry clay in 30 seconds while I mess with it to get it as straight as possible. Shaver says you need 12+ GPM for the driver but it is beyond awesome for my needs. Initially, I considered making it work on the skid loader... IMO on the back of the tractor is really the way to go, especially with one person doing the work.

It was a good learning experience (hydraulic fittings, ports, systems, etc. get confusing until you understand how it all works). I spoke with several mechanics and service departments to try and get this completed, and I think there is very little understanding of how these systems work, which is sad as they're very simple.

 

[J_J]

Glad everything is working good for you.

I would keep an eye on the clear tubing as the heat in a hyd system can get up to 175 to 200 degrees when working the system hard.