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berghild424
04-06-2012, 10:58 AM
we removed the king size bed and disconected the lines for the lift. drv said to follow the lines back to the reservoir and plug the lines. howard connected the lines....for some reason...i guess because we didn't have any way to plug them. None of the slides move. Is that because of air in the lines? we did lose a little fluid but it hardly seems like enough to make a difference. If it is air, how do we bleen the air off?

RGordon
04-06-2012, 07:57 PM
My guess and not knowing how they are connected, I would bet the hydraulic lines were connected together, allowing the fluid to just bypass. This will not allow the pump to build pressure with supply & return lines tied together. Neet to go to auto parts or a place that has hydraulic fittings and find proper plugs. Of course I may be wrong not knowing exactly how they are connected.

RickandJanice
04-07-2012, 08:10 AM
I think Ron's response is correct. With two way Hydraulic systems there is usually a pressure and a return line. Depending which order valves are opened in the solenoid as to which line is which. As fluid flows in one line to move the ram, the fluid on the other side of the ram needs to flow out, or the ram will not move. If you tie the wrong lines together or reverse them on one circuit, the fluid on both side of the valves equalize and the valves cannot open. This is basically what happened when you tied the two lines together on the the bed lift, so is probably affecting the whole system.

If it was just air, the slides would work but would jerk as the air bubble move through the lines. If that is the case, air can be worked out of the system by running the slides in and out in the correct sequence until the air is pushed back to the reservoir. You may still have to do this after plugging the lines to the lift individually. Run out bedroom first, then kitchen then living room. Run in in reverse order bringing the bedroom in last.

billr
04-07-2012, 08:35 AM
The actuators in these units only have one line to them and are pressure and suction operated. The control module decided what way the fluid goes. This is why you get rams that bypass internally and drop down on their own or won't move.

I wish they had pressure and return lines like "real" actuators! ha

Bill

porkchop
04-20-2012, 04:25 PM
Mine is apparently diferent than yours. Went out and looked. All rams have 2 lines to them.

Bill

RickandJanice
04-20-2012, 06:26 PM
Mine is apparently different than yours. Went out and looked. All rams have 2 lines to them.

Bill

All of our rams have two lines also. Have never heard of a hydraulic ram that operates on suction. The only hydraulic systems I ever worked with that used one line were those used in gas and oil pressure control systems. These type systems only need one line as the pressure on the back side on the ram will push the ram in reverse when the pump pressure is released and the fluid will flow back out the same line to the reservoir.

Motor31
04-21-2012, 10:17 AM
The rams all have 2 lines on my unit. One side pushes and the other free flows depending on which way I want them to move. None operate on "suction", only on pressure. The bleeding seal failure just allows the pressure side to flow or seep into the non presurized side allowing the ram to either drop or the unit to sag.

berghild424
04-27-2012, 05:51 PM
we did as we were told and plugged the lines. plugs provided by john deere in Yuma and everything is fine and we are on the road at last.