Help with pump

I have an 81 Chevy k20 and I went to get the blade ready this week and when I hooked it up the blade would go to the right but not left or up. My pump is under the hood and it looked like it was working. I did notice some hydraulic fluid leaking from the quick disconnects. Would this be enough for it not to work properly?
 

CT18fireman

Banned
Location
Western CT
I am assuming this is a Fisher with underhood belt drive hydraulics. If it is something differetn let us know. First I would check all the quick connects. If they are old or dirty the may not work anymore. The next thing would be to check the valve assembly. The cables and linkages may need to be adjusted or lubricated. Leaking suggest maybe excess pressure if connections are all tight. This would mean that there is a blockage somewhere in the system. Again look at the couplers and valve block.
 
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Armor

Member
Actually I'm not sure if it is a fisher or not but I'm in the process now of changing q. disconnects. Can this alone be the problem?
I bought the truck with the plow pump attached and bought a meyer "a" frame blade because that's what fit the frame.
 

CT18fireman

Banned
Location
Western CT
Is it a beltdriven system or an electric pump under the hood? Faulty or dirty couplers can cause a plow not to angle. You can have to get all the fuild out of the system. I used to run a filter inline with my belt drive systems.

Does Fisher still offer belt drives at all???
 
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Armor

Member
It is a belt driven system and has worked pretty good thus far. The fluid tank holds an easy 10 gal and I didn't change it yet but will with the connecters. I am literally praying that works. It not only didn't angle but didn't lift either. I'm not sure if Fisher sells belt driven pumps or not but I have seen belt driven pumps for sell in catalogs. They are pretty expensive. Have you ever used one?
 

CT18fireman

Banned
Location
Western CT
If you have a tank that big then it sounds like you have a central hydraulic system. Is this truck a dump body? Where is the tank that holds that fuid? There should be valves controlled by cables under the hood that control which was the plow goes. Sounds like something is out of adjustment.
 
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Armor

Member
Alot of people say that this thing could be turned into a dump truck real easy. The the filler for the tank is on the opposite side of the gas tank on the bed that goes to the hyd. fuid tank under the truck. It has a huge hose that takes the fluid to the pump. Also under the hood is a mechanism that has 3 directional valves on it and then there are the quick didconnects on the front. I turn and use the plow on from inside the truck but I guess the mechanism is in case something malfunctions. No one ever showed me how this thing works. I bought it last summer from a 70 yr old man who bought it from acity auction.
 

Rob

PlowSite.com Veteran
Just my .02 but that sounds like the older Fisher models with the belt driven pumps. The pump mounts on the engine just as the A/C or alternator would and has the three connects right at the pump. I would agree with CT18 that this rig has to have / or did have at one time, central hyd. otherwise there would be no need to have much fluid. (Unless it was running the mother of all plows :D )
 

CT18fireman

Banned
Location
Western CT
Too fix the problem I think that you would still need to adjust the valves somehow. If you cannot figure it out I would suggest taking it to a established Fisher dealer or to a truck shop that deals with Hydro systems found on medium size trucks. They should be able to help you.
 
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Armor

Member
Fireman I think you are right because why wouldn't the arm lift? Right? Or would the connectors keep the arm from lifting also?
You wouldn'y believe it, not only do I now have plow poblems now I have transmission problems. I had my truck in the shop all summer letting multistate transmissions work on my trans. This is the third time I have to take it back in now its still leaking!
 

CT18fireman

Banned
Location
Western CT
Automatic or Standard Transmission?

Dirt in the valves and connectors are a common cause of problems. Everything needs to be adjusted correctly to operate best.

My bet now is on the adjustment but I would still clean the whole system.
 

CT18fireman

Banned
Location
Western CT
Drain all the fluid out of the system.
The valves are wherever the hoses from the pump are diverted to control functions of the plow. Probably under the hood. I clean them by flushing the inside with kerosene. Then cleaning grease of the outside. Then apply light oil or WD40 to proect and lubricate the mechanisms.
Adjustment is usually made by turning nuts on the cables. This is a trial and error process to get the cables to work right. Important that they return to center or close when not being operated. A sticking valve can lead to shortened pump life.

May look into adding an inline filter for the system
 
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Armor

Member
Thanks for the advice! I will defintely do that as well. I'm just waiting now for the trans to get done. Oh yeah, then the outer u joints. Have you ever had to replace those?
 

Alan

PlowSite.com Addict
That "Not a real hard job" can turn into a real bear if the outer tube hasn't been out of the steering knuckle before. It's quite easy to mess up the threads on the end of the tube where the spindle nuts go. While you're at it you might want to inspect the ball joints as well. Once the axle is out you're almost there if you need ball joints as well. There is a special spanner required to replace the upper ball joint adjusting sleeve. No practical way to do the job without it.
 

Alan

PlowSite.com Addict
Probably not required as the "ball joints" on that setup only swivel in one plane and are located on tapered hole sint eh front axle "ears" where they mount. But it can't hurt either. The only thing that can be readily adjusted on that axle is toe-in. Caster angle is locke din by the axle tube and can be changed by tapered shims under the springs and camber is also built in and shim adjusted where the outer tube mounts to the sterring knuckle.
 
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