Third function kit install question

TheOldHokie

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From Summit FAQ
The FAQ is not informative. You can't use a sleeve since the valve has no provision for power beyond - there is no place to screw one in if you tried. It does not answer the question of how this valve works with down stream valves in the circuit or why it is plumbed backwards.

Obviously people use it and are happy without knowing the details of what its doing. I suspect there is no magic here and it works like any other open center valve installed in a pressure circuit. Personally I will opt out and use the generic kit with the Z50 valve and a power beyond sleeve. That's $125 cheaper and I can make hoses and brackets that suit my preferences with the savings.

At this point its become an intellectual itch which will subside with time.

Dan
 

CAC227

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MX5200
Apr 8, 2021
8
0
1
Colorado
D
So, myself installing a Summit 3rd function, I called Summit and spoke with them. The power beyond is fluid exiting the valve, no matter the valve, FEL valve or 3rd function valve, it moves on to 3PT or rear remotes or BH then back to tank.

Plumbing the FEL power beyond to the 3rd function P port (power beyond) will make it work in reverse, it should work Summit says. Summit says it was designed and tested to work as: FEL PB > 3rd function T port > through valve and out 3rd function P port back to manifold.

Summit, Land Pride and WR Long all use the same hydraulic schematic as OP mentioned.

Edit: This is plumbing the 3rd function valve WITHOUT a BH or rear remotes
Did you hook up the way it describes in the directions then? If so, everything working ok?
 

MSG H

Member

Equipment
L3901 HST RETIRED MIL.
Dec 20, 2020
45
20
8
VA
Everything is plumbed following the provided instructions. I’m waiting on heat shrink to arrive to cover the joy stick handle wire. And nylon loom to run the power wire, so I haven’t operated the 3rd function yet. So far only able to check for any leaks, all good there.

Im impressed with the Summit kit, especially the joy stick handle, which was what pushed me to buy the Summit kit in the first place. The buttons in the handle can be clocked to fit your likings. You can have them vertical, horizontal or set to 45 degrees.
 

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ayak

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L3301 HST
Feb 16, 2018
609
819
93
WV
Wanted to mention the item below is what I used to easily add power (along with a fuse) to the 3rd Function Valve I installed.
60880C6B-25D7-45CB-9760-8D224E691C07.jpeg
 
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ayak

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L3301 HST
Feb 16, 2018
609
819
93
WV
Care to share a link to where you bought theses? I’m going to pull switchable power from the fuse panel.
These came from Amazon

I used the same circuit as my hazards so I could have the tractor off and still take the pressure out off my dual lid grapple hoses right before disconnecting them.
 

Crash277

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Equipment
BX23S
Jan 17, 2021
846
622
93
Canada
You can find power sources already built into to Kubota. Look for blue tape on your wiring harnesses.
 

MSG H

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L3901 HST RETIRED MIL.
Dec 20, 2020
45
20
8
VA
These came from Amazon

I used the same circuit as my hazards so I could have the tractor off and still take the pressure out off my dual lid grapple hoses right before disconnecting them.
Excellent idea!

I was trying to save that circuit for the ROPS leds for power with the tractor not running
 

TheOldHokie

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Apr 6, 2021
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D


Did you hook up the way it describes in the directions then? If so, everything working ok?
Looking at Summit's images it looks like the nameplate on the valve has a hydraulic schematic printed on it. It is hard to see in the pictures but I believe this is what it shows.

OpenCenterSolenoidSchematic.jpg


That is a solenoid actuated open center spring centered double acting directional control valve. These types of solenoid valves are widely used modular components designed for sub-plate mounting and this one is attached to a simple aluminum plate with 4 x SAE ORB threaded ports corresponding to the four base ports in the valve body. The only thing "special" about this valve and assembly is the tank port has a pressure rating very close to the pressure rating of the P port so for all practical purposes T and P are interchangeable. As you can see from the schematic cylinder exhaust oil will be routed to the T port (P port if you hook it up backwards) which is the basis of my concern. It will work fine plumbed either way but it is not the best (I would say a poor) choice for use in a circuit with down stream valves. Their Z50 valve with an additional power beyond port would be a better choice.

I think my intellectual itch has now been scratched and you can now relax and enjoy the third function on your loader.

Dan
 
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TheOldHokie

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From my valve
OK - spool characteristics confirmed but missed on the T port pressure ratings and that adds another more significant element to my concerns. The T port pressure rating on the valve is only 1450 PSI and there is no internal relief and it wouldn't matter if there was because their is no direct to tank connection to relieve through. The valve relies on an upstream pressure relief device for protection.

It is installed in a circuit with both tractor and loader system pressure relief settings of 2437 PSI so any time you stall the 3rd function cylinder or ANY downstream cylinder that T port will be seeing 2437 PSI which is almost double its max pressure rating. Even a heavy load on a down stream cylinder (e.g. 3pt) could be enough to over-pressure the port and I would expect that to be a common occurrence if you are lifting heavy implements. I am not a hydraulics expert but my understanding is the main pressure concern on the tank ports in these types of valves is the solenoid seals. Only time and field testing will tell you if that is a problem in this application

Dan
 

CAC227

New member

Equipment
MX5200
Apr 8, 2021
8
0
1
Colorado
OK - spool characteristics confirmed but missed on the T port pressure ratings and that adds another more significant element to my concerns. The T port pressure rating on the valve is only 1450 PSI and there is no internal relief and it wouldn't matter if there was because their is no direct to tank connection to relieve through. The valve relies on an upstream pressure relief device for protection.

It is installed in a circuit with both tractor and loader system pressure relief settings of 2437 PSI so any time you stall the 3rd function cylinder or ANY downstream cylinder that T port will be seeing 2437 PSI which is almost double its max pressure rating. Even a heavy load on a down stream cylinder (e.g. 3pt) could be enough to over-pressure the port and I would expect that to be a common occurrence if you are lifting heavy implements. I am not a hydraulics expert but my understanding is the main pressure concern on the tank ports in these types of valves is the solenoid seals. Only time and field testing will tell you if that is a problem in this application

Dan
This is from Summits website describing the valve in the 3rd function kit. According to the description the T port is rated at 3050 psi. But is stamped differently on the valve apparently. Time will tell I guess on how it holds up. If it doesn’t I will replace with the valve you mentioned with a dedicated pb port.
1842A14A-2153-4B30-8C7F-D27C6BF0C37D.png
 

TheOldHokie

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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
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windyridgefarm.us
This is from Summits website describing the valve in the 3rd function kit. According to the description the T port is rated at 3050 psi. But is stamped differently on the valve apparently. Time will tell I guess on how it holds up. If it doesn’t I will replace with the valve you mentioned with a dedicated pb port.
Yes, that description was the basis for my initial comment. Summit is a distributor not a manufacturer and they put their own nameplates on the valves they sell so take that data with a grain of salt. If you look at the body of the valve you may find additional information stamped there. For example this is one of their P40 mono-block valves I have in the shop. The manufacturer's name and full order number is stamped on the casting. If you can find something similar on your valve it may be possible to find a full catalog description of the valve. Many distributors provide those documents on their websites but Summit does not.

Dan

20210411_141349[1].jpg
 

kubotafreak

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GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
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Arkansas, US
OK - spool characteristics confirmed but missed on the T port pressure ratings and that adds another more significant element to my concerns. The T port pressure rating on the valve is only 1450 PSI and there is no internal relief and it wouldn't matter if there was because their is no direct to tank connection to relieve through. The valve relies on an upstream pressure relief device for protection.

It is installed in a circuit with both tractor and loader system pressure relief settings of 2437 PSI so any time you stall the 3rd function cylinder or ANY downstream cylinder that T port will be seeing 2437 PSI which is almost double its max pressure rating. Even a heavy load on a down stream cylinder (e.g. 3pt) could be enough to over-pressure the port and I would expect that to be a common occurrence if you are lifting heavy implements. I am not a hydraulics expert but my understanding is the main pressure concern on the tank ports in these types of valves is the solenoid seals. Only time and field testing will tell you if that is a problem in this application

Dan
Hokie, Your logic is probably correct. On the P-T pressures having to be equitable in ratings. It is almost by mechanical law they have to with out a dedicated tank and pb port. I believe they de-rate only so a scenario in which the valve can provide work. This is not the most expensive type of valving, which fills the gap to not buying the factory option. Savings had to come from somewhere.
 

TheOldHokie

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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,735
4,477
113
Myersville, MD
windyridgefarm.us
Hokie, Your logic is probably correct. On the P-T pressures having to be equitable in ratings. It is almost by mechanical law they have to with out a dedicated tank and pb port. I believe they de-rate only so a scenario in which the valve can provide work. This is not the most expensive type of valving, which fills the gap to not buying the factory option. Savings had to come from somewhere.
At the risk of beating a dead horse :
  • Z50-1A-J2-AG12 - universal third function kit - $449,
  • P40-PB conversion sleeve - $22.50
  • FEL-BKT10- front end loader bracket with AG couplers - $49,95
Grand total = 521.45 delivered.

Now buy or make some hoses to plumb it and a mounting bracket for the valve and you will have a properly engineered third function valve free of all of these concerns.

Or call Summit and ask for a quote on a Kubota kit with Z50 instead of DO3 valve....

Dan
 

Bisleybob

Member

Equipment
B7500
Aug 15, 2020
69
78
18
Harding Pennsylvania
The factory option is the sme, just installed one on a 3901. Directions are basically the same as well. When connecting the electric, my personal preference is fused full time power, as you can bleed off pressure from the valve with the key off, momentary switch failing in the on position is highly unlikely.
 
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