Hydraulic question snow plow jerky

OK I have an old plow truck that uses a power steering pump for the hydraulic lift. The plow will lift great when cold . as the oil warms up and everything else, the plow starts to get jerky when I lift it. It also will not stay up. ( maybe a viagra in the oil would help this) what do you think, bad seal in the ram? or the spinchter valve ( or whatever you call the check valve) is letting the fluid back not holding the pressure in the ram. I did blow a hose and had to use some generic hydraulic fluid to get it back to the shop a few weeks ago. This truck has a great personality!! The electric windows only work when cold. The radio is stuck on a bad AM stration. The AC works great, not a good thing to have on a snow plow truck.

Let me know what you think.

I would try and flush the power steering system and use a good grade power steering fluid in it when you fill it again.. did it start after you blew the hose? or an ongoing prob? You could have some air in the line or cylinder....

My guess is that you have a Chrysler product with the Meyers Snow Plow Package. I would buy a new pump and put fresh fluid in the entire system. Those pumps were of a poor quality when new. You can try flushing and adding fresh fluid, but most likely it will be a waste of good oil.

Actually it is a fisher speedcast plow. USed to have its own belt driven pump. I rigged up a powersteering pump off of god knows what after the OEM pump went south. IT worked for two years. I do beleive the hydraulic fluid I used may have contaminated the system. THis morning I bled off some fluid after it quit working and it worked great for a while. I wonder if I'm sucking air, I mean the plow not me.

My wife wonders why I just don't get a new plow for my daily driver. Where would the fun be in that.

The Fisher used its own type of pump, and it has a different pressure requirement than the Meyers. I assumed the Meyers, since you said it was a power steering pump. I never gave a thought that you would have bastardized the system. If you still have the Fisher pump, then you can get a rebuilt one in exchange. The Fisher plow is much heavier than a Meyers and I don't think that the Power Steering pumps are up to the task long term. If you don't care about longevity, get another junk yard pump for $5.00 and get a few more years out of it.

YEs it is a heavy plow. IT is on an 86 dodge. I may try a new pump or modify the blade to fit the tractor that I should have bought in a few weeks. I tried to find a belt driven hydrauic pump and everything was quite exspensive.

Maybe a pump off a power stroke as they run the brakes and the steering, may be a bit stronger.

It is fun keeping this thing running. Actually the truck is sound, the plow just needs a good overhaul.
I just bought a new digital camera today so maybe I will post a picture of the beast.

If your still fight ting this I have a couple thoughts..

There may might be air trapped in the system after the hose replacement.

as far as swapping pumps.. might call these guys https://www.pscmotorsports.com/ . they are in the business of hydraulic steering and have pumps for most everything.. ya could call em and tell them what your up to, and I bet they have a suggestion.

Eric

I think I have a few issues, If I bleed the line it will work great for a few lifts. I think I'm sucking air. I just need to get a box of beer, and spend some time re-plumbing the system. The pump seems to have some snort left as it will create some good pressue on a hose un-hooked from the ram. May not be enough snort.