How to releave pressure to make connection?

[Samandothers]

I need some help. I have a WR Long thrid function valve to control my gapple tine. When i remove the grapple and go back to connect it I am having difficulties. I have to struggle like heck almost straining a giblet trying to connect the quick disconnets at the grapple.
I know when I remove the backhoe I move the controls around to relieve pressure and have never had a problem connecting it. However with the electrically controled valve for the third function am not sure how to relieve the pressure, or it that my problem?
Both connections I can not seem to slide past the ring on the male end far enought into the female end to allow the slip sleeve to move over the small ball bearings to lock the connection. What am I doing wrong?

 

[Willl]

However with the electrically controled valve for the third function am not sure how to relieve the pressure

On mine I activate the valve and move my lever back and forth a few times WITH engine off.

 

[mikim]

assuming everything is off with no pressure on anything -- take a plastic head hammer and give the male connector a rap with it (covered with a rag) --or you get fluid everywhere.--trick I learned here on tbn

 

[J_J]

If you have a male and female QD connector , the best thing , is to keep them plugged into each other, mainly to keep them clean, and to equalize the cylinder pressure, however even with that, in the middle of summer, the pressure will build up and it will be hard to disconnect. Just take a wrench and loosen the connector and a little fluid will seep out. Then you should be able to connect. Some people just take the male QD and press the tip real hard on the side of the loader arms to let the pressure off. You could also take a mallet and strike the male end do the some thing. Put a rag over the fitting when doing this.

 

[kennyd]

For the solenoid valve, just leave the key ON with the tractor not running so the valve has power and cycle the switch. Also make sure the grapple is closed all the way before you disconnect it so the weight of the grapple arm is not putting pressure in the hoses.

 

[irwin]

. Some people just take the male QD and press the tip real hard on the side of the loader arms to let the pressure off.~snip~ . Put a rag over the fitting when doing this.

It's what I do. Use to walk and get my brass punch, but that got old. Now I hook up the female to the tractor male, then tap the male fitting (from attachment) on something before even trying.

 

[Samandothers]

Thanks everyone for the feedback. Several good ideas to try. This time I loosened the connector to allow pressure to decrease. Next time before disconnecting I'll close the grapple all the way and try to operate the rocker switch with the engine off. I do normally connect the gapple connectors together to keep them clean. This last time once I removed the grapple and attempted to connect the ends to pressure was too high and I could not connect them.
Again thanks for the input folks!

 

[David_Kb7uns]

Have Kubota L3130 with LA723 loader, WR Long valve and ATI grapple on bucket. When changing to the other bucket or forks I set bucket on ground flat and then close grapple and shut engine off. Turn key back on with engine off and cycle switch in both directions. Disconnect hoses and put dust caps on, I once connected couplers together but if it heats up, hydraulic fluid expands and can make it harder to disconnect or reconnect (backhoe did it once to but it has a vent valve for the purpose). Some times I am temped to take a file to the quick connects on the implement side and either put in dummy plugs with vents or file a small groove in the poppet to let the pressure out.

David Kb7uns

 

[CurlyDave]

If you have the skid steer type of hydraulic quick disconnects, with the flat face, they are the biggest PITA I have seen in the hydraulic world.

Take a look at this thread http://www.tractorbynet.com/forums/hydraulics/131755-help-my-stucchi-disconnect.html to see how I handled this problem.

The real issue is that any increase in temperature creates a dramatic rise in hydraulic pressure in a closed system. Plugging the two connectors on your grapple into each other will only mean you can't get them apart if the temperature is higher than when you connected them.

What I have found is that if I buy a male and a female extra connector, and then plug the back of the connector tightly enough to keep dirt out, but not tightly enough to hold pressure, I can put one on each end of the grapple connections when I take it off. When I go to put it back on, it is pretty easy, although I sometimes have to resort to the caulking gun as explained in the link.

 

[J_J]

If you have the skid steer type of hydraulic quick disconnects, with the flat face, they are the biggest PITA I have seen in the hydraulic world.

Take a look at this thread http://www.tractorbynet.com/forums/hydraulics/131755-help-my-stucchi-disconnect.html to see how I handled this problem.

The real issue is that any increase in temperature creates a dramatic rise in hydraulic pressure in a closed system. Plugging the two connectors on your grapple into each other will only mean you can't get them apart if the temperature is higher than when you connected them.

What I have found is that if I buy a male and a female extra connector, and then plug the back of the connector tightly enough to keep dirt out, but not tightly enough to hold pressure, I can put one on each end of the grapple connections when I take it off. When I go to put it back on, it is pretty easy, although I sometimes have to resort to the caulking gun as explained in the link.

It only takes a small bit of fluid to lock those fittings, so if you are using the dummy connections, why not just add pipe caps over the threaded parts and if they won't seperate, unscrew the cap. You only need to do this on one side.

 

[AKfish]

If you have the skid steer type of hydraulic quick disconnects, with the flat face, they are the biggest PITA I have seen in the hydraulic world.

Whoee...! They are alot of great fun!!

With all the cold we've had this winter the latest problem has been with the female collars sticking. And the inside ring will remain stuck in a recessed position. Add in a tiny bit of snow here and there for some ice... Aarrgghh!

I'm gonna give the extra connectors a try this next summer. With the flat-face connectors - there's no simple way to bleed off the excess pressure after the sun gets a shot at the black hoses and cylinders. And packin' around 7/8" and 1 1/4" and 3/4" open ended wrenches is one more straw for the PITA pile!

J_J's note about a cap fitting on the end of the extra connectors is a good idea as well. Would make bleeding off the fluid a simpler exercise.

AKfish

 

[Samandothers]

Dave I like the caulking gun idea for some 'extra' strength to push the connectors together.
I am having a bit of trouble trying to visual the extra connector for bleeding some fluid. Are yall suggesting removing the existing quick fitting and add a 'T' and replace the fitting on one side of the 'T' and a cap on the other?

 

[J_J]

Dave I like the caulking gun idea for some 'extra' strength to push the connectors together.
I am having a bit of trouble trying to visual the extra connector for bleeding some fluid. Are yall suggesting removing the existing quick fitting and add a 'T' and replace the fitting on one side of the 'T' and a cap on the other?

No, The additional QD is only put on one end , say the QD female. You take a male QD with a pipe cap on it and plug it into the female QD, this lets the excess fluid caused by heat to expand into the cavity of the QD, and pipe cap.

It is a two piece adapter , one male QD, and one pipe cap. You could also bolt another fitting on the tractor to store this adapter, when it is not being used on the attachment.

 

[CurlyDave]

I am having a bit of trouble trying to visual the extra connector for bleeding some fluid. Are yall suggesting removing the existing quick fitting and add a 'T' and replace the fitting on one side of the 'T' and a cap on the other?

No, I do it like J_J says.

Go down to the hydraulic store and buy an extra connector, no hose, no "T", just a plastic pipe plug or pipe cap depending on what your connector has on the back of it. The secret is to put the extra connector on just as soon as you remove the implement from the tractor, before it has any time to sit & warm up.

I just screw the pipe plug or cap on by hand, which is enough to keep dust out, but doesn't really seal pressure. This eliminates making and breaking pipe connections on the back of the connectors, which I view as a much greater source of contamination in the hydraulics than any dirt getting through a hand-tight plastic pipe thread.

In many cases, you will only need one of these as J_J suggests. OTOH when I store my grapple, I close it before disconnecting. If I happen to put the dummy connector on the wrong hose connection, the closed grapple will allow pressure to build up in one side of the cylinder.

This prompts me to spend some time "blessing" the hydraulics, in a way that would make my pastor blush. It is just easier to buy two connectors and put one connector on each hose from the grapple. Same with my 4-n-1 bucket.

I actually have two sets of extra connectors one for each hydraulic attachment. There are times when they sit side-by-side in the yard while I use the forks.

 

[banjodunn]

if the thought of all these ideas does not interest there are quick couplers available that allow you to connect under pressure your local hyd shop should be able to help you out with these or you could try bare co they have a good site very helpful and good hyd page for those that dont know alot about hyd fittings i.e fitting sizes and styles etc

 

[J_J]

It seems like there is no standard for using QD male and female fittings on hydraulics. It would just make common sense to do this, for this reason. A hydraulic motor would always run in the right direction, by pushing on the lever, and reverse by pulling back. On cylinder action, the cylinder should extend to push down, and close by pulling back. The grapple would extend and close by pushing fwd. etc.

If I remember correctly, when you have the male and female QD's, the male goes on the output line/pressure line, and the female goes on the return line. Maybe someone can confirm this.


On the subject of connecting, flat face couplers with 3000 psi, with an attachment that has been in the sun for 8 hours, I have never tried that, but I have read that it can be done at low pressure, whatever that is. Maybe someone can confirm that fact.

 

[Samandothers]

Thanks for the clarification on the pipe cap to relieve the pressure. I understand now what is being suggested. I feel a bit better knowing this is somewhat of a common issue there are ways to remedy or reduce the problem.
thanks again all!

 

[jmc]

I stumbled across a simple solution to this that I don't think has been mentioned yet.

I have a WR Long grapple with their solenoid controlled valve on my Kubota. Since the grapple is used on a tracked loader as well, I plumbed the Kubota with the flat faced couplers, which magnify this problem. Do the usual pressure relieving procedures. Then with the motor off, try holding the valve open while making the connection. (Of course the valve must have power to it even though the motor is off.) Granted, it takes a second person on the operator's platform or a c-clamp or some duct tape to hold the button down during the hookup but previously it would only insert about 1/3 of the way and while holding the valve open, it goes in like butter.

My theory is that even though you go thru the various ways of relieving pressure, there is still a fixed, noncompressible volume of fluid trapped in a short hose between the valve and connector. Components within the quick connectors must displace a small amount of fluid to connect and there is no place for that fluid to easily go unless the valve is open at the time.

I have the same problem on the tracked loader and intend to try this the next time I hook up a hydraulic attachment on it. In the meantime, if anyone tries it on a skid steer type machine, let me know if it works. I'd also be curious if manual valves have this problem and if bungy cording them open helps with it.

One of these days I will hook up a momentary switch next to the QA connectors on the front of the Kubota. This switch will open the solonoid valve from the front to eliminate the second person or improvisation.

John

 

[Cat_Driver]

I have the same problem on the tracked loader and intend to try this the next time I hook up a hydraulic attachment on it. In the meantime, if anyone tries it on a skid steer type machine, let me know if it works. I'd also be curious if manual valves have this problem and if bungy cording them open helps with it.

In the CAT they have a button in the cab that you push and it releases the pressure in the lines ( Hydraulic oil bypass )