Deere #1 Rear SCV Problem Power one way, none the other, Float works

RedNeckRacin · Jan 8, 2013

So I have been using my deere to run a post hole auger. It's not quite as simple as it sounds. I have to use both spools to get the auger to run. The #1 spool has to be put in float and connect a hose to it; the other "pressure" hose connects to the #2 spool and controls the rotation of the auger. I don't understand exactly why that's the only way it will work but that's what I got figured out.

Anyways, I tried using a regular cylinder on my bale grabber the other day using the #1 scv and I had power one direction, none the other, and the float detent still worked. No problem, I thought I had a coupler that wasn't seated fully or a frozen coupler. So I tried my best to make sure everything was seated correctly and nothing. So I switched the hoses to the #2 scv and everything worked fine. Ok, we got a more serious problem. I again tried making sure the couplers were seated all the way in the #1 scv. Still same problem. From what I can figure out and I'm basically looking for a confirmation on this; I think I have some sort of blockage in the spool on the tractor. The reason I say this is I can hear the hydraulic pump bogging the motor down no matter which direction I pull/push the lever. Is my only option to basically tear the spools out of the tractor and clean them? Not too big of a deal except I'm going to have to do it outside in this wonderful PA weather. I can see the hose jump on the good side of the spool when I put pressure to it from the spool, but not the other. Any other ideas?

J_J · Jan 8, 2013

Hydraulics:
Type: open center
Pressure: 2828 psi [195.0 bar]
Rear valves: 1 to 3
Mid valves: 2 (optional)
Pump flow: 15.9 gpm [60.2 lpm]
Total flow: 22.5 gpm [85.2 lpm]
Steering flow: 6.6 gpm [25.0 lpm]
Steering press.: 1900 psi [131.0 bar]

You should only have to plug in the auger hose and set the lever to detent or bungee it on.

The return from the auger can go directly to tank unless you want to reverse the auger.

If you want to use the auger in fwd and rev, then plug in the auger hose into one set of work ports.

Zebrafive · Jan 9, 2013

I can't understand how you got a hydraulic motor to work at all with the valve in float. Maybe this valve was acting as a return to tank?

I would swap couplers from the non working valve for the set from the working valve before tearing into the valve.

J_J · Jan 9, 2013

Something definitely does not sound right.

In float mode, all port are connected to tank. so therefore no pressure. That is why there is a float mode. The bucket is free to move up and down, following the conture of the ground.

You should have been able to plug into one set of the work port QD's, and move the lever on for flow. The speed of the auger would be dictated by the pumps GPM, or the position of the lever valve. If using solenoid valve for auger, the hyd motor will be instant on, and speed dictated by the tractor engine rpm.

For continuously hyd motor operation, you would tie the lever open.

For proper operation of a hyd motor, you should be using a motor spool valve, that will let the hyd motor coast down with attachments that have high centrifugal motion.

You can use either lever valves with motor spools or solenoid valves with motor spools.

RedNeckRacin · Jan 9, 2013

I wasn't sure if I explained myself very well. Let me try again.

I'm talking about the rear remotes not the mid valves.
The auger does not turn at a high RPM so spooling down is not an issue. The motor does turn faster with increased engine rpm or moving the 2nd scv lever farther forward.

I'm not exactly sure why I cannot run the auger off of one remote. I HAVE to use two. And to get it to work, the #1 remote is acting like the return. (Hence why I have it in float.) I could not get the auger to turn otherwise. It would act like the auger was locked up trying to just use one remote.

I'm not trying to figure out how to run the auger. I have gotten it to work previously just fine. My question now is, why I don't have hydraulic pressure when I try and use the remote on a normal double acting cylinder?

oldnslo · Jan 9, 2013

Redneck,

Your Auger should turn if both hoses are connected to the same SCV. On the 1st stage it does sound like there is a restriction the valve some place. Not sure how the valves on your deere are made but should be a common pressure port and two seperate tank lines that connect common at some point in the valve body. If one of these tank cores is blocked it would allow flow one direction and not the other. Another possibilty is that your valves have built in load holding checks on the work ports and one of these is not opening properly.

Can you install a gauge in the QD's on section one and see if it will build pressure on both?

Take a piece of hose and loop the ports together on section one with gauge installed in this line. Do you build pressure when the lever is moved one way and not when the lever is moved the other? If yes, swap the hose ends from one QD to other on the same valve section. If the pressure still builds when operating the lever in the same direction this would indicate you some obstruction preventing return flow back into the valve. Very unlikely it is the QD on the tractor since flow would be trying to open it but still would be the easiest thing to change.

Good luck.

J_J · Jan 9, 2013

Recheck all the hoses for correct setup.

All levers to neutral.

Remove all work port hoses and then find the auger hoses and connect to the same spool, port A and B. Only operate that spool, and the auger should turn.

You can't be in float unless you force a spool into float.

Who did the hose connection for the SCV?

RedNeckRacin · Jan 10, 2013

There are only two hoses. I made up a set of hoses to have a poor man's third function on my loader by using the rear scv's. The hoses have worked fine for all of my attachments up until a few weeks ago when this issue started. The #1 scv has a detent for float so I dont need to hold it there.

RedNeckRacin · Jan 12, 2013

Ok I tried running the auger again today. You guys were correct in that it turns when connected to just one SCV. I dont know why I thought I needed to put one in float and power it with the other. I had used it like that for awhile though.

SO onto today's test. I tried running the auger forwards and backwards on the #2 spool. Auger turned both ways just fine. Went back to the #1 spool, and it turned one way fine but would not turn the other. No problem. Ill switch the hoses. It rotated opposite of the first time but would still not spin both ways. So i got to playing with the lever and I noticied that my detent for float will no longer hold the lever that way and it still sounds like its trying to apply pressure to the spool from the hydraulic pump even when I move the lever all the way to float.

Anybody have any ideas? I was poking around it today, and it sure looks like its going to be a bear if I need to pull the whole thing out from under the tractor to work on it. Could I have blown a seal or something else apart?

J_J · Jan 12, 2013

What is the brand and model number of the valve for the BH?

Open the can on the bottom of the valve and check/clean and tighten everything.

Look at the detent groove and steel balls for corrosion. Replace parts if necessary and lube everything good. Make sure drain hole on can is on the bottom.

Do you have regen on the second spool?