Last month when to use 751 after snowstorm. Fluids ha bee topped up, had been parked unused 2 mo. Turned on, lowered bar, gave it time to warm up before toyching any controls. In a minute or 2, suddenly started rollong back. Went to the oedal, which didn't seem stuck, but didn't respind, other would not activatevto raise arms. Shut off and climbed out. I have the idea there is a switch to take hydraulics out of line, but don't know where. Is parked where there is a culvert drop below the back engine door. An couple weeks later, gradually lowered itself. This week climbed in without checking fluids. Started right up, but only movement was tilt-down in respinse to pedal. Could not raise arms or move wheels. So yesterda a mechanic friend came and found small hose near front piston and leaked under pressure and drained the fluid. Opened cab and checked all fittings and hises for leaks or loosenessz replaced the bad hose, then turned on to see if he saw and leaks under pressure, and it immediately rolled back with the down-tilt avtivated as soon as turned on. Was able to turn off and jump down before to fell it reach maximum tilt, which probably would have tipped it over. We got it closed, and is still rolled back. Besides draining fluid to relieve the pressure to lower the machine, I have no ifea what to do. HELP!
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walio123
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it seems that the plunger on the hydraulic valve is stuck or blocked by something. Raise the cabin and push the white platic caps down /those that seat bar pess when is lowered/. Press the pedals and watch their rails move freely. See if the plungers of the valve move freely.
walio123
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hydraulic release is near to seat with red plastic handle.It must be pulled up and pedal must be pressed and will release boom or bucket.
We had the rails apart to move aside to check all hoses and fittings tight. Moved freely manually. Not sure about valves and plungers, because could stay there and learn. Those whit vettical switches moving freely. I went and climbed in, pulled up that red square knob. Took a lot of wiggling, only got it up an timy bit. Pushed pedal at same time, but don't know how far up is possible. No luck. Tomorrow will go spray that and try again. Aside from getting it released back down, I think what is causing it must be electric. A short in a safety switch?
walio123
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There is nothing electrical that can cause this problem. Everything in 751 is mechanical. I think you mix the rails of the llevers with pedal rails. The pedals along the side of the main frame have rails that move when you press the pedal in the various directions. At one end, they are attached to the plunger of the hydraulic valve. Just follow them where they are going and see if they move the plungers on the valve. Here you have to see the plungers moving and the pedals are free, the two plungers must protrude equally from the valve body. To be able to press the pedal, you have to press down the white plastic caps down to release the pedaling movement. They are on the side frame near the hand levers. I'm sure that you have something mechanicaly stuck.
