So we have a 2000 model National 1100 series crane that is having an issue with the rear outrigger. They are the out and down type on the rear and the passenger side outrigger going up/ down will not come back up. We had to basically use the drivers side outrigger and push the machine to the passenger side to help push this outrigger up. Would that be in the valve block or the actual cylinder? The pressure maxes out when you go to retract it and you can see the hoses jump. Any place to start would be great...... Thanks
I think the simplest thing for you to do is dismount the cylinder, drain the oil. Stroke it back and forth by hand. Im betting that it won't move easily
you either ave a bad lock valve on cylinder or the packing is causing the cylinder to leak by internally.
Swap the lock valves, quick and easy....
Gonna try that first, seems like the easiest thing to do.
I do not think your cylinder is bypassing internally. Your pressure should not max out if the cylinder was bypassing the internal seal bad enough to not move. I vote for the lock valve.
You suppose theres a piece of crap stuck in there not allowing it to open fully? I am assuming theres little chance of cleaning out that sort of thing?
To be honest , most times trying to clear a small piece crud is a time killer and you wind up 50 % of the time replacing it any way . If your time counts for anything replacing it and going bad to work is better . If you have the spare time and parts are a couple of days out maybe
yep id say lock valve
well, found the problem........ threads completely torn out of the ram! Gonna try and have it fixed but my guess is they are going to have to machine a new one.
Glad you found the issue, I suppose when u were leaning on the jack to get it up you were jamming it and the lock valves were actually holding the cylinder from dropping down while moving...