Third function dirverter valve vers True 3rd function valve

[Turbys_1700]

Yep. Don't know why they didn't bring the gusset down to the tip edge. Those old implements I am pulling out of the over grown honeysuckle don't give too much. Not a difficult fix though. Just got to get out the saw and welder.

 

[ovrszd]

Only thing harder on a Grapple than old iron is old rocks.

 

[k0ua]

Only thing harder on a Grapple than old iron is old rocks.

Ever run across any "young rocks"..

 

[scdeerslayer]

I have a simple question.

If you have a thumb and you close it and curl the bucket on a backhoe does the curl have to overcome the pressure of the thumb? To push it back onto the cylinder?

If not how does the thumb hold the load in place? How is a thumb setup? Is there a maximum pressure for the thumb in relation to the bucket?

With the thumb valve closed it locks the cylinder in place. If both valves are open, then yes one can overpower the other, and it will move fairly fast, faster than normal. That's basically the same principle as the quick-dump or "regen" feature of some loader valves.

 

[LD1]

The limiting factor of what "locks" the cylinder in place is the pressure in the hoses. IF you have an undersized cylinder on the thumb you will blow the hoses right off. Use a thumb that was designed for the machine or a machine with similar power and you should have no issues

 

[SSdoxie]

ovrszd
Thanks for the information. My Bobcat is as you describe, FEL-rear remotes-3pt. As is I can only lift/drop and curl partially (is not uniform in motion) I also know my 3pt is last as when I have my remotes in float the 3pt will not work. In going over my system I do not see a power beyond as that port is covered by the rear remote valves. There does not appear to be a port at the loader control valve either. Perhaps I am not looking correctly. Ill call Bobcat tomorrow and check. I dont see any exposed tubing as everything appears to be bolted directly to the trans housing

My grapple operation is as follows. Operate the loader controls to place the hay grapple over the bale and engage the hooks. Right now I stop and grab a rear remote lever to engage the hooks, so there is a gap between loader and and grapple. It appear I need a true 3rd function to be able to operate the hooks from a switch on the loader joy stick, otherwise I would still need to stop and move a rear remote lever. With a diverter I would momentarily loose a loader function when engaging the hooks.
Question - will the loader arms and curl still hold when the diverter is operated? Example loader at full height and grapple set to place bails on hay stack. If the diverter is on the lift circuit, will the loader arms drop when flow is diverted to release the hooks?

The loader valve does have PB already on it. Look at the steel line coming off the inside (left side) of valve running back to the rear. You will see what appears to be an extended female thread adapter the the line is connected to on the valve. This is the PB.

To use a true 3rd function you would remove this steel line then using hose connect from control PB fitting to 3rd function valve then another hose back to where that steel line was connected.
With only 8 GPM @ 2500 engine RPM trying to multi-function all 3 circuits at same time would slow all of them down so much that it would be faster to operate each at a time. I can and have used multi-function of loader and bucket but in most cases it is quicker to move one at a time.
Bobcat does (or did anyway) offer a diverter valve kit for these tractors. Diverter installed in bucket circuit. Price was a little too high for my thinking and would probably source parts online, but their kit does include a different bucket spool to eliminate Regen function and spool could be ordered individually if needed. The Regen function when using grapple would only be an issue if you moved joystick fully to far right while in grapple mod using bucket dump.

 

[ovrszd]

Ever run across any "young rocks"..

That my friend is a very "deep" question. Relevance needs to be determined.

 

[Sysop]

Timeline needs established too. Which came first? Dirt or rocks?

I'm interested to learn, my wife often says that I'm "older than dirt"...

 

[ovrszd]

I also think I need to try to clarify something.... Correction if needed is appreciated.

So, tractor running, no hydraulic requirement. Pump pushes fluid thru the FEL valves, thru the 3rd function valves (if equipped), thru the rear remotes, thru the 3pt and dumps back to the tank. No pressure established. Open flow. This cycle can go on indefinitely and create minimal heat because there is virtually very little resistance.

When a valve is activated, regardless of where it is in this chain, it first closes the "open" path. Then it diverts this flow to whatever function is desired. Let's say lifting the FEL. Suddenly the relaxed open flow of fluid has been disrupted. Now we begin to build pressure. Whatever pressure required to lift the FEL is exerted. No bypass is required. Suddenly we reach the end of the FEL lift cylinder's stroke. Now the PB in the FEL valve is activated. All excess pressure is pushed down the line. If no other action is required, it quietly dumps into the tank. Let's say we have also activated the 3rd function. Now the pump provides pressure to the FEL lift, it bypasses down the line thru the PB because the lift cylinder has reached it's max stroke, now the 3rd function has the pump's full ouput. Action will be quickly completed. Now the PB in the 3rd function valve is activated. All excess pressure is pushed down the line. If no other action is required, it quietly dumps into the tank. This process continues as long as a valve is activated. When us operators are done required pressure the whole system goes back to the relaxed state and fluid is simply dumped back into the tank. If this makes no sense or if I'm in error please let me know. I think it's beneficial for everyone to understand how this works.

 

[ovrszd]

Timeline needs established too. Which came first? Dirt or rocks?

I'm interested to learn, my wife often says that I'm "older than dirt"...

Well, if she intends that to be an insult she should say older than rocks. Dirt is made by a combination of things. Rock dust. Decayed organic material. Moisture. Kinda like the chicken/egg thing. If there were no rocks present, there would be no rock dust.