Ok so I know its a bit early, but I am working on the plow truck. I have a 84 F250 with a 351W. I put the 9 foot Fisher plow on 2 years ago, and it was a used plow system. Only paid 500 for it. So anyway, the issue I am having now is the plow will not stay up. It slowly creeps down. Also, the plow has a hard time turning left, not right. If I keep slapping the joystick left, it goes full speed for a few seconds, then slows right down. I greased the mount where the plow and ram move. I also pulled the valves out of the valve body and cleaned them up. They are free moving, and the joystick is tight and seems to work fine. Is the valve body going? Is the pump going? Not really sure where to go from here. I was going to get a valve body but they are like $400. I guess I could get a used one but might be stuck in the same situtaiton. The truck is not a road plow, only a yard plow.

Any help would be appreciated!

 

check your grounds, make sure they are clean and tight

 

This is the old style non minute mount run off the added pump and valve body. I dont see any other ground issues with the truck.

 

Leaking down is a bad seal in the lift cylinder. Going fast one direction and not the other could also be one of the directional cylinders has a bad seal or it may have air in it.

For the directional cylinders, I would take the plow off, turn it up on it's face, and move the A frame back and forth and see what it feels like. This is also how I bleed the air out of mine(though I have a Meyers). With the blade on it's face and the A frame sticking up in the air, I push the A frame back and forth and then leave it all the way one direction, and take the fitting off the cylinder that is fully extended(most chrome shaft showing). I then take a squirt bottle and put fluid directly in that cylinder till it overflows. I put the fitting back in, and move the A frame back and forth, and then try to put more with the fitting out, and keep doing this till I can't get anymore fluid in the cylinder. This gets most of the air out, and is a lot easier and less messy than loosening the fittings and letting them bleed fluid out all over the place.

After you get all the air out, lay it back down and hook it up and see how it reacts left and right. Getting the air out might fix it. If it doesn't, look for a cylinder that may be leaking out around the chrome shaft. That one may have a bad seal inside. Also get someone to move the joystick back and forth while you are under the hood, to make sure the valves are moving full travel with the cables.