OK so there will be a continuos duty air compressor at the site so I was thinking of using long travel air rams to lift the weights and then using limit switches attached to solenoid's for engagement and disengagement. So continuos duty won't be an issue.
So what this person wants me to build is a way to run a water pump using counter weights. As the weight falls it turns the pump. The pump has a working torque load of 36 ft lbs @ 3600 rpm. I don't even know if this is possible so any help would be awesome.