Hey guys I am trying to diagnose an issue that just started on my man lift. After about an 1/2 to an hour of operation I seem to lose hydraulic pressure to all componets boom telescoping drive etc. each componet but I will use the boom for example will start to function then jerk down like a pulsing I can push it through but its a struggle if I mess around enough going back and forth it will snap out of it and work again but not for long I do need to get it fixed though also I can switch to auxilary power and all functions work fine im thinking its the pump but any help would be appreciated Its a gasoline kholer powered motor with a vickers pump the manual became pretty vague when it came to the pump 1990 JLG 45 HA top Gun
The pulsing you describe makes me think pump as well. A pressure gauge would be helpful.