John Deere 850 compact. Installed remote hydraulics, no pressure, very slow movement

[JMD373]

Hello everyone,

We have 2 john deere 850s on our farm, one came with remote hydraulics when we bought it, the other did not. Recently installed remote hydraulics on the one that was lacking it, we got the valve bank from john deere, lines and bracket we had custom made, obsolete... Anyways, I've double checked some obvious things (to me) such as lines hooked up exactly as they are on our other tractor, hyd fluid in tractor.... When I first installed i hooked a quick coupler up to each outlet of the valve bank before I put them on the hoses of my sprayer, started the tractor and moved each lever - hyd fluid shot out of each port properly. I got my sprayer all hooked up, went to move the booms and the action is incredibly slow, cannot even see them move unless you rev the tractor way up. A hint in all this may be that the tractor is not loading down at all, with out other 850 hooked to this sprayer you can hear the RPMs drop a bit when you activate the remotes when its working properly, this nothing and not even a twitch in the lines when you bump them.

I am wondering, is there a pressure relief valve in this setup somewhere that I am not seeing that needs to be adjusted when installing remotes? Or some other shut off in the system that would be closed when the tractor didn't have any remote hyd, but now needs to be open? Some have mentioned to me sometimes there is a set screw or something of the like that may need to be installed or taken out, but no one I know is familiar if there is anything like that on this tractor...

Only other thing I noticed is, as can be seen on the John Deere parts catalog website there were 3 different valve bodies made for this tractor,
152 - SCVH (850 TRACTOR SN. 009001- ) (950 TRACTOR SN. 012001- ) (CESSNA 30932 CAV)
153 - SCVH (850 TRACTOR SN. 009001- ) (950 TRACTOR SN. 012001- ) (CESSNA 30932 CBH)
154 - SCVH (DUKES FLUID POWER 1627-AN)

After a second look I see that the one on my properly functioning 850 has the first above (152) and the new one we got is the last (154) above. They are all very similar, however could the hoses be plumbed differently to my unit versus the other? Again though, wouldn't that either lug the tractor, break something, or not work at all if I had it plumbed wrong?

Thanks for any help anyone might have! much appreciated.

Joe

 

[Leejohn]

TX jim might remember this. Go look at the parts list again and see if you find a 3/8 pipe plug that should go in when adding remote valves or loader. If I remember right it was under a good size plug on the back side of the rockshaft control. It also seemed like I had to remove a hard line replace with another to get the 3pt to work. You could also look at your other tractor to check the hard lines. I would also remove the plugs on the back side of the rockshaft and see if one has the 3/8" allen head pipe plug. Keep in mind I'm going back to 1980 so this might not be just right.

You might also check the Quick couplers and make sure they are seated good.

 

[JMD373]

Thank you for the reply. I am sure I did not receive a pipe plug, but it is possible that I may be missing it. The parts I bought were not part of a kit since, like you said, been a while and the kit was obsolete. So all I really got from John deere was the valve bank and levers, and no instructions. I did take a few plugs off, but those both looked like pressure reliefs to me, spring underneath. Do you remember by any chance what that plug was for? I ask because today I took the male ends of the quick couplers off my sprayer again, just plugged them into the valve bank and ran the tractor so I could see what happens, hydraulic fluid comes out of each one properly just no where near the flow you would think should be there, so for some reason I am lacking good flow. The 3 point hitch still works great though even with a load, which makes me think it can't be the pump itself, I'm stumped! ... But thanks again I will try to locate that plug tomorrow!

 

[Leejohn]

That pipe was to make it PB for the loader and that other line I was talking about was to make the 3pt work. With out that plug the 3pt is working like it should and loader is only getting the over flow. I don't think there is any pressure at the loader to amount to anything. That plug I'm talking about was about a 7/8" socket to remove and nothing under it. You have to look inside the hole to see the threads. Lets hope Jim well jump in here. He knows how to lookup the parts at JD real good, or he might remember.

 

[J_J]

If the tractor hyd was working before you installed the remote valve, then the valve hookup is the problem.

Do you have the PB from the loader or from the side of the tractor going to the IN port of the remote?

Do you have the PB adapter installed on the remote valve.

Is the tank line going to tank?

If your pump is good, and pumping full volume, and the valves are connected correctly, then the pump flow will pass through all valves to tank.

When you operate the remote valve, you are directing the flow to go to the work ports at full volume.

What kind of pressure are you getting on the remote valve.

 

[Tx Jim]

TX jim might remember this. Go look at the parts list again and see if you find a 3/8 pipe plug that should go in when adding remote valves or loader. .

Leejohn
I can't remember a plug as it's been waay too long. Maybe plug(parts key 8) is the plug in question as it's not listed with RS piston cap without SCV kit. I wonder if inner seal is in place on PBY fitting(parts key 22)? What's this tractors serial number????

 

[Leejohn]

I think it is #8. Maybe that well help him.

 

[JMD373]

Thanks guys, I will go look again but it seems from that picture #8 would be if you had power beyond going from SCV to a loader or other implement? On mine I have the PB going right back to the rockshaft cap, which is the way my other one is plumbed... Heres a picture of the setup, if maybe will jog your memory!

Thanks again for the help
Joe

 

[JMD373]

I havent checked that one plug right above the knob, but could that be it? I assumed that was a place for another line or something, since it looked like a boss fitting... I will check & I will get serial

 

[JMD373]

serial # (at rear or tractor above hitch on trans)

CH0850S021227