I-600 allis chalmbers forklift

[maxxforce]

How do I increase the main mast oil pressure lifting pressure?

 

[4570Man]

You’ve probably got a weak pump or leaking cylinder seals vs low relief pressure.

 

[maxxforce]

Yeah I agree. Was hoping Limp it along for now. You got any info on these forklifts?

 

[4570Man]

I don’t know anything specific to that model but in general if the pump is worn out and not making pressure or the cylinder is bypassing fluid there’s nothing to be done besides fix the problem. What is the forklift doing?

 

[maxxforce]

It was supposed to have a 5000 pounds lift capacity. If I try and lift 2000 Chevy half ton (approximately 3800lbs) It’ll lift the truck to the point that suspension is completely extended but that’s it.

But if I tilt the mast forward far enough And then apply all the lift pressure it does the same thing. But I can draw the mask back easily with the tilt so then the truck is off the ground.

 

[4570Man]

Does it leak down unusual fast?

 

[maxxforce]

If I leave the forks off the approximately 2 feet it takes about three to 4 days for it to leak down.

 

[4570Man]

It sounds like the cylinder seals are pretty good. It also sounds like the pump is making pretty since the curl cylinders work. I think a pressure test on the lift function would be the next logical step.

 

[maxxforce]

I’d like to find a good service manual for this forklift. I’ve bought three now but none are actually informative when it comes to the forklift hydraulics. Just the industrial tractor it falls under.