# Hydraulic pump!



## Sharpshooter77 (Jul 19, 2006)

Hey guys I have finshed my flatbed/dump on my 1993 F-250, I have a 12volt monarch hydraulic pump, that is hooked up to the lift for the dump. the other day I had 2300 pounds of junk on the truck and the bed would just go up 2 or 3 inches, it couldn't lift it. I wanted to know is there a way to adjust these pumps to make them push more, or do i get a bigger pump. At work we have an F-550 with an electric/hydraulic pump and that thing will push anything. I would like to get my hands on that pump but it think my boss would be a little upset, Also I was thinking or running a hydraulic pump off the motor of the truck, there anit nothing like a PTO. Let me know what you guys think, I don't know a whole lot about hydraulics.

Thanks 
ussmileyflag

Shane


----------



## wild bill (Feb 10, 2007)

*pump*

well depending on the model of the pump you can adjust the pressure up a little ,but first of all did you have a water level load ,or was it all in the front ? clutch pump or pto drive hydraulic's are nice but expensive .:waving:


----------



## Sharpshooter77 (Jul 19, 2006)

Now that I think of it the heavier items were towards the front of the truck. I should have had them on the back so it would be easier to push the bed up. But still the cylinder is rate for 2 to 3 tons of pushing power. the hydraulic pump really seemed to struggle.


Shane


----------



## wild bill (Feb 10, 2007)

*pump*

find the model number and look up monarch on the net and look for the pressure relief . good luck :salute:


----------



## B&B (Nov 4, 2006)

Best place to start is to get a pressure gage plumbed into the pressure line so you can check the pump output. Might just need a relief adjustment. Do you have good electrical supply to the pump motor? Large enough cables? Good connections? 

If you do change the relief setting, don't run it over about 2400psi or so as it really taxes the pump and electric motor with it set that high..and it shouldn't need to be any higher than that regardless. 

Which brings up the next question...Since this is a custom install are you sure the geometry is correct on the lifting mechanism?


More questions than answers I know .


----------



## Flipper (Nov 1, 2001)

Geometry was my thought to. You can have a 10 ton cylinder and proper pump output and not be able to lift 1000lbs. I have seen it. No matter what you lose some efficiency in the mechanism. The only setups that lift close to the cylinder max are front mount direct systems with telescoping cylinders. All scissor and direct undermounts loose some efficiency because they are moving less vertical, especially at the start of the lift.


----------



## Sharpshooter77 (Jul 19, 2006)

The setup that I have on my truck is a scissor lift. I bought the scissor complete with the cylinder. The lift is more towards the front of the truck, it is just past the middle of the bed. Also I was checking out my hydraulic pump and its a monarch M-319-0157, I did find the relief vavle and it was backed out kind of far and it was finger loose, you could see that the lock nut that is on the set screw was not seated either. So I turned the set until it was set and made it tight, and the pump is working great no problems at all seems to push very well. I think the set screw backed itself out and it had just enough power to push the bed up and nothing else. Thanks for the help guys,


Shane ussmileyflag:salute:ussmileyflag:salute:


----------



## wild bill (Feb 10, 2007)

*pump*

glad to hear it !


----------



## B&B (Nov 4, 2006)

Gotta love those easy fixes... 


May want to get a gage on it when you get a chance just to be sure it's not set too high.


----------



## basher (Nov 13, 2004)

Get a gage on it.

I've got a liftgate right now someone cranked up the PR and has "done" the O-ring in the D.A .cyl. we have to rebuild the ram and adjust the PR to reasonable setting.

It's the side effect of having a LITTLE knowledge, and a lack of the proper tools and a incomplete understanding of how, why and when to use them. See it in plows all the time guys setting the PR and CRs without a gage Then they wonder why it blowing it's hyd. mind and or bending things up.


----------



## Wicked500R (Sep 6, 2007)

Don't know what kind of hoist your running but another thing to consider if this is a custom setup is the diameter of the cylinder. A fatter cylinder will lift more weight but will be slower.


----------



## bike5200 (Sep 4, 2007)

As B&B said, make sure your wire sizes to the pump is right and the ground is very important too. Had problems with my electric pump on my dump. The truck up-fitter had the pump grounded to the frame by the pump. Had to run a ground from the electric pump to the engine block, work much better after that was done


----------

