Daisy Chaining Loader Valves

[jigs_n_fixtures]

I bought a second loader valve for my tractor to operate the top and float on the 3-Pt.

I have the mounting and hydraulic connections figured out, pretty much just follow thee picture from the Summit Site

The only question I have, is: Can I run the tank line on the first valve into one of the tank ports on the second valve, and then run from the second tank port to the tank?

 

[Vigo327]

Can I run the tank line on the first valve into one of the tank ports on the second valve

Are you saying your 2nd valve has more than one tank port? IF that's the case you probably could do that, but i'd verify the port you're thinking of is actually a '2nd/alternate tank port' vs something that is plugged for a reason!

Or, the 'safe' option would just be to Tee the tank lines together outside the valves.

 

[jigs_n_fixtures]

There is a spot on both sides of the body, with the T for tank cast in. I assumed they connect within the body. Guess, I should pull both plugs and see if I can blow air between them.

 

[jigs_n_fixtures]

I found some old Nimco Literature, from the generation between, the generation I have, and eh current generation. They say the valve can be configured two ways. And open center setup, which uses T1. A closed center load sensing configuration, which uses T2. I’m still going to see if they are interconnected.

 

[mrmikey]

Yes you can. The only oil that flows thru them is the return oil from the opposite, non pressurized end of the hydraulic cylinder or the return from a motoring spool. The actual flow from the pump runs thru the PB port that's why you need the PB plug so you don't pressurize the return circuit when using a downstream valve.

A closed center load sensing configuration, which uses T2. I’m still going to see if they are interconnected.

Not trying to be an a$$ and asked with respect but you do realize open and closed center are two totally different systems?

 

[LD1]

Yes you can TEE the tank/return lines but thats it. Cannot tee the pressure or PB lines

 

[jigs_n_fixtures]

Yes you can. The only oil that flows thru them is the return oil from the opposite, non pressurized end of the hydraulic cylinder or the return from a motoring spool. The actual flow from the pump runs thru the PB port that's why you need the PB plug so you don't pressurize the return circuit when using a downstream valve.


Not trying to be an a$$ and asked with respect but you do realize open and closed center are two totally different systems?

The literature on the valve shows two different flow diagrams as available from the factory, suing the Sam body. You order what you want/need by option codes

The open center, uses P1 in, and T1 out, and the Power Beyond adapter screwed into P4, with metal plugs screwed into all the ports the factory flow diagram doesn’t use, and plastic dust plugs in the ones you use.

The closed center, load sensing, configuration uses P2 in, and T2 out, with P3 as the power beyond. P1 and T1 are not used, and I‘m guessing shipped with the steel plugs installed in the ports you don’t use to plumb it in, and plastic plugs installed in the ones you do use. The valve installed stock, and the duplicate I bought as a spare, (and have now decided to install to control the rear, and control top and tilt), has steel plugs screwed into P2 and T2, and all ports not plumbed on the stock loader valve. And has the plastic plugs in all the ports the one currently installed for the loader. Which, indicates to me, that they are both the open center versions. The casting numbers, and rivet tags are identical, except for the date code. The installed one has 2010 code, and the new one a 2011.

Pretty sure I have the duplicate of my loader valve. Just not sure if T1 and T2 are connected internally. I‘ll pull the T2 plug and see if air flow between there and T1.

Other than that, I have the plumbing figured out. Currently a 12-mm hard line runs from the P4-Power beyond, to the inlet to the rear valve mounted on the top of he transmission, with the 10-mm, T1 line next to it and running into the transmission adjacent to the fill plug.

Plan is to mount the new valve at the back of the right fender, so I can reach it facing front, or turned sideways in the seat, to run the top and tilt on the 3-point. Which puts it near the seat belt mount and the bottom of the ROPS, and provides good options for solid mounting. Heat mold/shape some Kydex sheet, as needed to make it a clean installation, which looks factory.

Plumbing will extend the hard lines to the new valve, and then back into the transmission at the stock locations. Similar to the Summit diagram included in the original post, but with the tank lines run through the new rear valve. Instead of routing the two tank lines the Summit diagram shows. It should all end up looking like a clean factory option installation when I’m done. At least that is the goal.. Worst case tee into the existing tank return line from the second valve. Just won’t look as clean.

 

[Vigo327]

They say the valve can be configured two ways. And open center setup, which uses T1. A closed center load sensing configuration, which uses T2. I’m still going to see if they are interconnected.

So im trying to work this out in my head having never actually worked with a closed center system at all.. But in open center the pressure and tank ports are connected until you shift a spool (or install a power beyond sleeve). In closed center the pressure and tank ports are NOT directly interconnected. So if both tank ports were connected internally, there would still be a path from the pressure inlet, to the 'open center' tank port, over to the 'closed center' tank port. So they are likely not interconnected internally UNLESS the plug in the closed center tank port is not a simple short plug but actually extends in further and intercepts/blocks a passage, sort of like a power beyond fitting with no way out.

I guess you will know as soon as you unscrew that plug and look!