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Hyster H70B steering hydraulics

I replaced the hoses on the steering and now I got no steering!!!!

There are 4 lines at the base of the steering column two to the assist cylinder and two to the pump. The pump is belt driven and it has two suction lines from the oil tank. Something got crossed in the process, anyone have a flow chart for the system?

Steve
 
I have a Vickers vane pump on mine,and if the pump is disconnected ,its quite difficult to get it working again......I have wide experience of these pumps on trucks and have never had any difficulty with them,just on the Hyster.
 
Not sure if it helps, I have an S70E cushion tire, early-mid 80s, GM 250-6 propane mill.

In my steering its powered by the transmission hydraulics, not the lift + tilt hydraulics. That pump has trouble priming itself or pushing out any air, could be wear, suction line gapped, I have yet to figure it out, but I'm also not trying very hard :D

My fix for the fail-to-prime is to reach down into the abyss with engine at idle and crack the tube-nut on the main tube fitting for the pump's output, engine loads up slightly and ATF comes rushing out suddenly, and I tighten the hex at that moment. Then it works just great.

If hoses got crossed that could be tough to sort out, do you have the old ones to play detective with, checking lengths, etc?
 
Four hoses in a cylindrical base would be a Hydro steering....TRW Orbitroll ,or a Hydroguide......some of these ,if hose connections are wrong,the steering acts as a hydraulic motor,the wheel will oscillate ,and when touched,will suddenly begin to rotate......with force that will rip your thumb off,if you are foolish enough to grip the wheel.......My Hyster has a simple valved booster cylinder and a conventional steering box.....Ive never looked ,but I would assume the cylinder is also Vickers TRW.
 
The steering is kinda starting to react. I took the lines off the pump and got flow thru the pump with a syringe filling some hoses I dipped in a bucket of oil. The steering is still very sluggish and hard with full weight on the axle. I pressurized the hydraulic tank slightly to see if that helped scavenge oil to the pump. On turning the steering wheel I am getting some buzzing from aeration the pressure helps but still there. I am trying to go lock to lock, some movement is smooth some jerky.

Steve
 
That sounds like my H80B ....I have to get free flow from the pump,then attach the hoses with the motor still running and oil going everywhere.....Im pretty sure there is something wrong with the valving in the pump head,but I seem to recall I hve swapped most of the pump with good ones from trucks...........problems with forklifts is you need them right now,and when you dont need them ,there is always something else to do,and they dont get fixed.
 
I spent a lot of time and money on a rebuilt engine, new clutch, entire brake system and all the hoses. I want to have this right. I put a propane system on the forklift and am adding carriage shift. My lil Clark Clipper is great in tight spots, "Bertha" the 24K Hyster is a bit awkward inside and the lil Cat/Mits is just a bit under gunned at 5K. This old H70 is built like a Panzer and is smoother than the Mits with a clutch Vs a torque converter.

Steve
 








 
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