Hooking Hydraulic lines up on Backhoe

[K5lwq]

You need to get the pressure off of the cylinders, not the lines. Use a jack to pick up on the frame of the backhoe. Once you get the weight off the outriggers, work the valve for the outriggers to equalize the line pressure. Then you should be able to connect the lines. If not, then you can work on relieving line pressure. Before trying to hook the lines up on the tractor, work the remote valves with tractor off.

To remove backhoe, use blocks as Richard suggests.

As Lou said, do not remove fittings to release pressure. This pressure is holding everything up. Also hooking lines together helps, but only if you don't leave weight on the cylinders.

 

[ptsg]

Like most people, I've been also trying to come up with a solution that could help this issue.

What if someone would build a small portable tank with a vent, drain and a male + female couplers on top. When there was the need to take the backhoe off, it would as simple as hooking up the backhoe lines to this tank, where couplers would be open to the tank and the vent would allow it to vent the pressures changes during temperature changes.

 

[paulfun9]

I'm assuming the rag is just to catch the oil. We tried this a bunch, the nipple (plunger) does not budge on the female end no matter how hard we press. I mean, we had two grown men pushing with all our might...not a budge.

I have watched two very strong men try in Vienna to do this with a smile when they gave up, I simply grabbed the line and smacked the end with a mallet twice. Pressure relieved.

As others have said with outriggers holding things up if there are no locks for them to rest on you could be be getting bleed back past the valve and just build pressure back in the line and lowering it with any attempt to relieve the pressure.
Most times it痴 just pressure in the line from the temperature change and that is easy to deal with, with a plastic or wood mallet and a quick tap on the tip of the fitting. Use a towel to catch any fluid.
Since we/you are unsure if this is just due to heat expansion or bleed back into the line it is recommended that you heed the advice of jacking it up and taking the wieght off the outriggers.
When I remove any hoe temporarily in the field I always lower everything to the ground before disconnecting and haven稚 had to do anything else unless the temperature change from morning to noon is extreme. If your temperature changes are normally extreme having the hoses ran into each other with the hoe on the ground should be all that痴 needed.
With mine in the garage I set it an a custom built set of castors with the outriggers locked up but before building the castors having a consistent temperature in there we had no problems with line pressure even with the outriggers down and holding up the wieght of the hoe.

Be careful with the jack as the balance is critical. Actually I would much rather use straps and rig them to the loader to lift it just enough to put blocks under it.

 

[nforktractor]

You need one of the WAITE tools, I've always have had trouble with getting pressure released on FEL lines and such, this tool makes it very easy:

Ken's Bolt on Grab Hooks <<Hydraulic Tools>>

 

[ChrisRyan]

Quick Update

I got the lines connected to the tractor early this morning. Temp outside was similar to the temps and conditions when we took it off. I played with the levers of backhoe a bit and then finally grabbed a rag and hammer and tapped the valve. Pressure released and hook up was easy. Once it stops pouring outside, I'll get the backhoe hooked to the subframe of the tractor.

 

[ChrisRyan]

You need one of the WAITE tools, I've always have had trouble with getting pressure released on FEL lines and such, this tool makes it very easy:

Ken's Bolt on Grab Hooks <<Hydraulic Tools>>

That looks like a very useful tool. I watched the video and saw him release on the male end. Wonder if it works on the female end of the coupler also

 

[ChrisRyan]

Funny, I was just in the hydraulic shop today investigating fittings which are designed to alleviate this common and annoying problem. The owner said I can buy the fittings and do it myself (I had photos of the stock hoses and fittings) and he directed me to a nearby vendor (Morse) so he wouldn't have to mark it up on me as the middle man. I had read previously and he confirmed that Parker makes "Connect-Under-Pressure Quick Couplings."

I'm not a fan of fighting my equipment and the idea of "scheduling" my backhoe attaching/detaching around the current temperature is more ridiculous than I can express... so I'm going to change out the stock ones. I have to confirm the pressure and trade size and then will price them out and let you all know what I find. Don't hold your breath though... not sure when I'll have a definitive answer.

This would be great. I'd be curious on how they actually work in the different scenerios. I'm with you, seems ridiculous that the only solution is waiting for the right temp, or begin the process of banging out all the time doesn't agree with me

 

[ericm979]

I got a set of the Parker connect under pressure QCs. They are super stiff to operate. For me with not a lot of upper body strength they're too stiff to connect if they're hanging free and not on a bulkhead. I've been meaning to make some hydraulic connect gizmos for my grapple and backhoe that have QCs on a tee with a valve and cap or breather. The idea is to connect it to the implement's QCs after I remove the implement from the tractor. Then when I put the implement back on I can use the valve to release any pressure from temperature changes.

 

[ericm979]

This would be great. I'd be curious on how they actually work in the different scenerios. I'm with you, seems ridiculous that the only solution is waiting for the right temp, or begin the process of banging out all the time doesn't agree with me

I don't like hammering on stuff either, but if you damage a QC they're easy to replace.

The other way to release the pressure is to break open the hydraulic system. I usually undo a quick connect from the line its on. On my grapple the QCs have JIC adaptors screwed in to their NPT threads. JIC connections are easier to undo and they can be removed and reattached multiple times without degrading the sealing ability. NPT threads seal by deforming so the seal will degrade after some removal and reattach cycles. And they seal better with thread sealant.

 

[Diggin It]

I keep a soft faced hammer handy. Use the rag over the connector and gently but firmly rap the detent ball. Also keep a small dowel handy to be able to do it on the detent ball in the female connector if need be.