hydros.biz Lowrider hydraulics information

Here is am example of the early type found on most lift-gates. This one block (IMO) is a very rare block, as it has seven ports instead of the usual six or less.  Port # 9 is rare. This block might have been made for something other than a lift-gate, possible a wheel chair lift.

This is a view of the motor end. note the pin to line up the motor at about 3:30
and then note the pin hole at about 9:30

we are looking at the block as it mounts in this position.  The mounts can be clocked at 9-6-3 depending on where you are looking at it.

same block, note casting,
same block, here is how the pump head mounts, top ports are at 12:00

also note this block has seven ports, very unusual. (we will talk about ports later).

#1) would be an electrical dump valve or a manual dump valve.
#2) is the early internal check valve. A spring with one or two balls at each end, within a round sleeve was the design.
#3) was usually just the fitting to hold the check valve, sometimes this port would be used as the pressure port.
#4) is the pressure relief valve, the ball and spring would go along this port, and the ball would sit just to the right of the pressure port from the pump head. As the pressure built up, it would unseat the ball and fluid would return back into the tank. We would tighten the fitting as tight as we could to compress the spring to prevent it from opening and releasing any fluid.
#5) would sometimes be used as the pressure port for Lowriders.
#6) is the port for the return to inside the tank
#7) is the external port for the return fluid. Tank returns were never used with lift-gates.
#8) is the original pressure port for lift-gate pumps, and we also used as the pressure ports before riders started to gut the blocks out for better performance.
#9) is unknown at this time, this is the mystery 7th port, I will study it later. It was never used for Lowriders. My guess its just another return port.
#10) is the internal pressure port for the pump head and block.

Please note, I did not garbage up the image with a watermark, you use it, please tell who made this and posted it. Hydros.biz

you could,  and I have done this; use the center port for pressure to one cylinder, then "T" a fitting for a hose over to the second cylinder. That's it. Just two hoses and a built in dump valve on the block and you have a setup with 12 volts.