Quck-Connect vs. Residual Pressure

[ericm979]

Do the connect under pressure valve type connectors go on the implement or the tractor? I was assuming they went on the tractor but your explanations make sense if they're on the implement (or hoe etc).

Thanks

 

[Luke'sScreenName]

They go on the side where the pressure is.

 

[sdef]

The connect under pressure type of QDs help a lot but were not a total solution for my FEL grapple bucket as the pressure buildup in the grapple hoses while in storage due to temperature expansion would still build up enough pressure to make mating the connectors difficult- but possible. The fix, provided by someone on the hydraulic forum was to add a hydraulic QD fitting to a PVC plumbing cap/pipe that has a tiny hole drilled into it. Just install the caps onto the device's (backhoe, grapple, etc.) fitting when storing the piece and residual pressure never builds up due to the vent hole in the PVC cap. Over time a small amount of hydraulic fluid will leak out of the cap due to expansion within the hoses. So don't store the device on your concrete driveway, etc.

 

[DaveK OR]

Thanks to all who helped me to resolve this problem. It turned out that the backhoe was stored in a way that put weight on the dipper cylinder, and that was enough to prevent easy connection of the QD's. Once that issue was resolved, the connections fitted together much more easily. I considered using "under-pressure" fittings, but that looked like a rather expensive solution to a simple problem. I've found that I still get a little bit of pressure build-up, but not enough to prevent the fit-up.

 

[Luke'sScreenName]

Good! :thumbsup:

 

[JRobyn]

This forum could really use a "like" button. Muhammed?

 

[Texasmark]

My experience with either is:

1. Equipment has to be off and hyd levers have to be cycled to bleed off residual pressure.
2. You cannot connect to a connection that has pressure against it, like a FEL with the bucket up in the air.
3. Heat makes fluid expand and put pressure on the fittings making it impossible to connect without bleeding first.
4. Gen. hyd fittings are a PIA.