kennyd
Advertiser
What the tech said is technically correct, setting it up with PB is the best way. But, OTOH...it was working fine before and it should work fine now. The addition of the PB circuit will NOT give anything "more power".
kubota L235dt Hydraulic issue
- Thread starter captjack
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captjack
Silver Member
So you don't think I will see a difference in performance in the loader and three point by plumbing it correctly ?
I am ignorant when it comes to hydraulic flow. There has to be some advantage to using the PB set up when installing the loader.
Right ?
I am ignorant when it comes to hydraulic flow. There has to be some advantage to using the PB set up when installing the loader.
Right ?
AKKAMAAN
Veteran Member
I dont think that either....the thing ist that we do not know at what rpm pump is rated for 6.2gpm....and we do not know yet at what rpm captjack runs his system during the "test".....if pump is rated 6.2 at 1800rpm, and he test at 600rpm.....flow is almost down to 2 gpm...compared to 10gpm.... now we have a difference....
I agree that an over sized valve will do the same job, as long as we allow this over sized valve operate with a fully closed center (lever at max stroke)
My thought was that spool of some reason get a full move to its designed end (center closed), and that would allow part of flow divert to tank and also prevent valve building full pressure (PRV open)
I have tried to find info about the spool travel for this valve but it is not there......wonder if there is any adjustments in the linkage.....
J_J
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The increase in performance, will have to come from higher psi, and since you did not change the pump, you have the same force, assuming the relief is set up correctly. If you are thinking speed of operation increase, again that is regulated by the GPM's from the pump. If the other valve was plumbed correctly, you should have had max force from the pump, when the valve went into relief. If you installed the new valve correctly, you will have the same force and GPM's to the system. If I understand you right, you plumbed the input to the new valve from the pressure port of the flange, and the output of the PB, to the return on the flange, and the return from the new valve to the return line to tank. That should be correct. The first valve to operate will use the fluid to activate a cylinder, however, the FEL valve has priority, and if using all the fluid, the 3pt will not work, until the FEL valve releases some of the fluid, or returned to neutral. If the FEL valve is only using some of the GPM's, the remaining fluid from the pump can be utilized by the 3pt.
AKKAMAAN
Veteran Member
Agree with kennyd....If entire pump flow is forced through your new valve, there should be NO extra benefit with the PB plumbing....
I would love to see how much the spools in the valve are supposed to move, and how much they actually are allowed to move now....this to make sure center get fully closed at end of lever movement.....
J_J
Super Star Member
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- 18,952
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I noticed your valve has regen, then don't expect to have rated power until the lever is out of regen. Regen represent speed. About 4 times normal.
Addition,
Regen function, the forth position, loses about 1/4 of the force available. Just pull the lever back a little to regain the full capacity of the hyd circuit.
Addition,
Regen function, the forth position, loses about 1/4 of the force available. Just pull the lever back a little to regain the full capacity of the hyd circuit.
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AKKAMAAN
Veteran Member
"regen" regenerative, means that return flow from rod side will be forced back to capped side, so pump will only need to provide flow/volume equal to the rod...
Basically like this pic...
regen was initially designed to help pump fill the void, and prevent cavitation and/or air into capped side when a cylinder extend is over loaded from inertia and/or gravity....basically what happens when tipping the bucket....
another positive effect with "regen", is that the rest of pump flow can be used to increase speed of other simultaneously used functions....
Basically like this pic...
regen was initially designed to help pump fill the void, and prevent cavitation and/or air into capped side when a cylinder extend is over loaded from inertia and/or gravity....basically what happens when tipping the bucket....
another positive effect with "regen", is that the rest of pump flow can be used to increase speed of other simultaneously used functions....
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OP
captjack
Silver Member
I am trying to get my head around this.
I have the flange block psi outlet plumbed to the in side of the loader valve. The return (not pb) plumbed back to the flange block. This is not right according to the manual. It says clearly to use a PB valve when using the aux flange hook ups.
It works the way it is now, with the exception of poor performance - i.e I have to push down on the loader valve to get the 3pt to pick up heavy loads. works fine with rear blade/rake etc but if i have to pick up my 8 ft disc it struggles.
It almost feels like its not getting all the fluid psi it needs to work properly.
I went to friends house tonight and looked at his 3000dt kubota. His has a flange block like mine one line goes to the inlet on the loader valve, the PB port on his valve goes back to the flange and the return line out of the loader valve goes back to the sump on the 3 pt housing. This is the way the manual says to do it.
Why if there is no difference , would it be plumbed using the PB port ?
There has to be a reason it is set up this way right ???
Is the way i have it set up now (with out pb going back to flange port) causing to much flow / to little flow ?
just about any time I am using the loader i have to rev the engine up high - usually pegging the foot peddle
thoughts ?
ps AKKAMAN - according to Brand the valve closes the center the min you move the lever
I have the flange block psi outlet plumbed to the in side of the loader valve. The return (not pb) plumbed back to the flange block. This is not right according to the manual. It says clearly to use a PB valve when using the aux flange hook ups.
It works the way it is now, with the exception of poor performance - i.e I have to push down on the loader valve to get the 3pt to pick up heavy loads. works fine with rear blade/rake etc but if i have to pick up my 8 ft disc it struggles.
It almost feels like its not getting all the fluid psi it needs to work properly.
I went to friends house tonight and looked at his 3000dt kubota. His has a flange block like mine one line goes to the inlet on the loader valve, the PB port on his valve goes back to the flange and the return line out of the loader valve goes back to the sump on the 3 pt housing. This is the way the manual says to do it.
Why if there is no difference , would it be plumbed using the PB port ?
There has to be a reason it is set up this way right ???
Is the way i have it set up now (with out pb going back to flange port) causing to much flow / to little flow ?
just about any time I am using the loader i have to rev the engine up high - usually pegging the foot peddle
thoughts ?
ps AKKAMAN - according to Brand the valve closes the center the min you move the lever
OP
captjack
Silver Member
JJ
If I understand you right, you plumbed the input to the new valve from the pressure port of the flange, and the output of the PB, to the return on the flange, and the return from the new valve to the return line to tank.
this is not how it is plumbed - I only have 2 lines going to the loader valve. 1 from the flange to the valve and 1 returning to the flange(not from the PB)
If I understand you right, you plumbed the input to the new valve from the pressure port of the flange, and the output of the PB, to the return on the flange, and the return from the new valve to the return line to tank.
this is not how it is plumbed - I only have 2 lines going to the loader valve. 1 from the flange to the valve and 1 returning to the flange(not from the PB)
AKKAMAAN
Veteran Member
the min you move the lever What is "the min you move the lever"???
It start restricting the center when lever start moving from neutral, and should CLOSE the center shortly before lever reach max movement.....this make the CENTER RESTRICTION a variable restrictor and will build a variable pressure to work port....
I am sure you and "Brand" are misinterpreting each other in the communication....