How to add a valve

[bcarwell]

I'm adding a grapple to my FEL. I am rerouting the existing two hoses coming out of my conventional FEL control arm that normally go to the curl two way cylinder to a double selector valve (DSV). The two hoses normally coming from to the curl two way cylinder that used to go to the FEL control arm are then being connected to the DSV.

Similarly I am adding two new hoses between the grapple's two way cylinder and the DSV. With the DSV in one position, pressure is routed to the curl cylinder and controlled by the FEL control arm. With the DSV in the other position, pressure is routed to the grapple cylinder and controlled by the FEL control arm.

There are lots of threads on various other ways to do it. But here's my problem. I've not seen threads yet about specific practicalities on exactly how you disconnect a hydraulic line and insert something.

I have some hydraulic books on order that hopefully will help but I'm impatient to get started.

Specifically:
1. If your tractor has been sitting, is there still residual hydraulic pressure in the lines such that if you disconnect a line at the FEL control arm hyrdaulic fluid spews out ?
2. I gather you teflon tape connections, but after you make the connections there has got to be air in the lines. How do you bleed it out.
3. I've also gathered that hydraulic lines aren't just let flopping around subject to repeated flexing and movement. But are there any rules of thumb about how to secure, route and support them or just common sense. I think most of my runs/connectors will be short with the longest being the two new hoses from the DSV to the grapple cylinder.
4. After making the connections (and I assume just bleeding someone per 2), do you just fire it up and try it and look for leaks.
5. Are there any other "gotchas", basics, or general practical physical tips to doing the hookup I have described above that a newbie wouldn't know. Like using a torque wrench on the connections to XYZ ft.lbs., etc. Or is it pretty straightforward.

Thanks for any and all advice to a first time hydraulic hacker...

Bob

As you can tell from the foregoing I'm a little nervous about breaking into a perfectly good, working Kubota B7500 and FEL.

 

[AKKAMAAN]

Specifically:
1. If your tractor has been sitting, is there still residual hydraulic pressure in the lines such that if you disconnect a line at the FEL control arm hyrdaulic fluid spews out ?

pressure can be applied into system by....

-pressure from pump running

-pressure stored in an accumulator, even if engine/pump is turned off

-trapped air in the system

-pressure from external force, like FEL hanging on hydraulic cylinder, or machine with hydrostatic transmission parked in a grade, with no parking brake applied, etc, even if engine/pump is turned off

-gravity

other than above, residue pressure should leave system in a few seconds, from natural internal leakage...

Avoiding oil from dripping out when disconnecing hoses etc is hard....but can be done with the help of a vacuum pump, but that takes a air sealed tank system and a especially designed tank structure......

2. Air bleeds out by it self, thru all connections and seals......

3. yes there are "rules" or recommendations....can´t find em just now....hope some one can fill in on that...

4. yes, check for leaks by applying max pressure...

5. If you do not know how to tighten a fitting....use a wrench with a short handle....

 

[kennyd]

There are so many threads on adding a diverter, did you search them? I realize you are gun-shy...but all the info is in here.

1. With the tractor OFF, lower the FEL and 3PH and then move the controls around some to relieve pressure.

2. NO TAPE! Use PTFE based dope. Pieces of tape can foul valves and filters. System is self bleeding.

3. Common sense.

4. Yep-fire it and cycle everything multiple time to check for leaks and purge air.

5. SEARCH!

 

[dex3361]

DON'T CHECK FOR PRESSURE LEAKS WITH YOUR HAND HYDRAULIC OIL UNDER PRESSURE CAN PIERCE THE SKIN. USE A PIECE OF CARD BOARD AND THE OIL WILL SHOW ON THE CARD. The stream of oil may be very fine and close to the leak it can cut/pierce but the threat is less the farther you are from the leak.

Before making or breaking hydraulic connection bleed the pressure off of the system with a loader it is done by lowering the bucket, turning the engine off and moving the loader controls in all directions to relieve pressure.

 

[TTTTTT]

I'm adding a grapple to my FEL. I am rerouting the existing two hoses coming out of my conventional FEL control arm that normally go to the curl two way cylinder to a double selector valve (DSV). The two hoses normally coming from to the curl two way cylinder that used to go to the FEL control arm are then being connected to the DSV.

Similarly I am adding two new hoses between the grapple's two way cylinder and the DSV. With the DSV in one position, pressure is routed to the curl cylinder and controlled by the FEL control arm. With the DSV in the other position, pressure is routed to the grapple cylinder and controlled by the FEL control arm.

There are lots of threads on various other ways to do it. But here's my problem. I've not seen threads yet about specific practicalities on exactly how you disconnect a hydraulic line and insert something.

I have some hydraulic books on order that hopefully will help but I'm impatient to get started.

Specifically:
1. If your tractor has been sitting, is there still residual hydraulic pressure in the lines such that if you disconnect a line at the FEL control arm hyrdaulic fluid spews out ?
2. I gather you teflon tape connections, but after you make the connections there has got to be air in the lines. How do you bleed it out.
3. I've also gathered that hydraulic lines aren't just let flopping around subject to repeated flexing and movement. But are there any rules of thumb about how to secure, route and support them or just common sense. I think most of my runs/connectors will be short with the longest being the two new hoses from the DSV to the grapple cylinder.
4. After making the connections (and I assume just bleeding someone per 2), do you just fire it up and try it and look for leaks.
5. Are there any other "gotchas", basics, or general practical physical tips to doing the hookup I have described above that a newbie wouldn't know. Like using a torque wrench on the connections to XYZ ft.lbs., etc. Or is it pretty straightforward.

Thanks for any and all advice to a first time hydraulic hacker...

Bob

As you can tell from the foregoing I'm a little nervous about breaking into a perfectly good, working Kubota B7500 and FEL.

Hi Bob,
Heres a thread when I did a front QD mod for a snowplow and for a future grapple control. I see you want to run off your FEL curl functions, but if you can run it off a PB (power beyond) port to a valve thenyou don't have to touch that and still have your curl function. If you have the time and a few more $'s, Kennyd and JJ can guide you through it I'm sure. I added an extra valve in line from my FEL control valve to control the front QD functions. It has worked great for the plow angle, but will easily work well with a grapple or other things.

Good Luck Dave

http://www.tractorbynet.com/forums/hydraulics/154201-front-qd-mod-plow-hookup.html