john deere 6220 hydraulic testing.

[CRFarm]

The block on the rear of my hydraulic main block has 3 ports to hook the gauges to. Which one is for what test and what should my readings be? I checked with my dealer and he said I need to get a different manual to find my problems. The manual I have is how to fix the problems, not to diagnosis the problem. He gave me the manual # so I looked it up. $875.00. I think not. Since Deere lost its right to repair case there going to get you for the info. My problem is my cylinder leaves don,t return to nutural when it gets to the end of the stroke. It has been this way since I bought it, My son has a 6420 and it does the same. It doesn't matter if I use remote 1 2 or 3. When I return the leaver to
nutural it sounds like a relief valve is sticking. I can tell the engine is working the pump. I can get to quit by taping the leaver the other way or by turning the steering wheel a little. I thought I would start by checking the preasures. I have the 200 series valves. My dealer can't tell me if the leavers should return to nutural by them self or not. Other than this all systems seem to work ok. Any help ?

 

[Jim.ME]

The block on the rear of my hydraulic main block has 3 ports to hook the gauges to. Which one is for what test and what should my readings be? I checked with my dealer and he said I need to get a different manual to find my problems. The manual I have is how to fix the problems, not to diagnosis the problem. He gave me the manual # so I looked it up. $875.00. I think not. Since Deere lost its right to repair case there going to get you for the info. My problem is my cylinder leaves don,t return to nutural when it gets to the end of the stroke. It has been this way since I bought it, My son has a 6420 and it does the same. It doesn't matter if I use remote 1 2 or 3. When I return the leaver to
nutural it sounds like a relief valve is sticking. I can tell the engine is working the pump. I can get to quit by taping the leaver the other way or by turning the steering wheel a little. I thought I would start by checking the preasures. I have the 200 series valves. My dealer can't tell me if the leavers should return to nutural by them self or not. Other than this all systems seem to work ok. Any help ?

Go to the JD Ag and Turf bookstore and download a free copy of the operator's manual for your tractor. Click on Equipment publications, Type 6220 in the search box for model. You will need the serial number to get the right one. Here is a link to the site.

JD Ag & Turf Bookstore

I looked at one of the Op Manuals and it read like the 200 series valves don't have the detent and kick out to neutral. The 300 series have that option.

 

[wore out]

The block on the rear of my hydraulic main block has 3 ports to hook the gauges to. Which one is for what test and what should my readings be? I checked with my dealer and he said I need to get a different manual to find my problems. The manual I have is how to fix the problems, not to diagnosis the problem. He gave me the manual # so I looked it up. $875.00. I think not. Since Deere lost its right to repair case there going to get you for the info. My problem is my cylinder leaves don,t return to nutural when it gets to the end of the stroke. It has been this way since I bought it, My son has a 6420 and it does the same. It doesn't matter if I use remote 1 2 or 3. When I return the leaver to
nutural it sounds like a relief valve is sticking. I can tell the engine is working the pump. I can get to quit by taping the leaver the other way or by turning the steering wheel a little. I thought I would start by checking the preasures. I have the 200 series valves. My dealer can't tell me if the leavers should return to nutural by them self or not. Other than this all systems seem to work ok. Any help ?

The three test ports are steering, pump compensating pressure and system pressure. Sorry, I can't tell you which is which, offhand.

It's a COMPLICATED pressure and flow compensated ,(PFC) hydraulic system and LOTS of things have to interact properly or it becomes mess like you are seeing.

When no hydraulic functions are in use system pressure is supposed to drop to a low "standby" pressure of (IIRC) in the 500 to 600 psi range.

To troubleshoot this you are going to have to study and understand how PFC systems work, including what "dime valves" are, a repair manual, at least three suitable hydraulic gauges and a flowmeter.

 

[620 John]

With the 200 series SCV's there's 2 settings for the SCV levers. One is no detent (C in the pic) which will allow the lever to release back into neutral when the lever is let go. The other is detent mode (A in the pic) which keeps the lever held in the operating position even when the hydraulic cylinder is fully extended or retracted. Sounds like the levers are in detent mode??? But that wouldn't explain why pressure is still being built up with the levers in neutral. I'd have to do some more research on that.

 

[CRFarm]

I have the operators manual. The setting A is for using a hydraulic motor and setting C is for using a cylinder. All are set in the C setting. All the dime valves are where they should be acording to my technical manual.

 

[used red MN]

What wore out is talking about seems to be at the root of your problem. Does the system just basically have switches in the cab and electrical solenoids operate the valve? Or is there a physical cable or rod connecting the lever and the valve? It sounds to me like it is just electrical and the switch or lever actually “centers” but the system action does not follow suit and remains on high pressure.This is very likely a problem with the PFC system as wore out describes. How to fix it probably requires following the manual’s testing process to diagnose it. I take it you are saying the cost of a manual is $875?

 

[wore out]

I have the operators manual. The setting A is for using a hydraulic motor and setting C is for using a cylinder. All are set in the C setting. All the dime valves are where they should be acording to my technical manual.

So now you have the Tech Manual?

 

[CRFarm]

I have the tech manual. It only tells you how to remove and install all the parts. To find the problem I need the diagnostic manual. Yes it's $875 My valves are manual not electric. I guess I think they should work better than my 2 cylinders from 70 years ago that are simple. They return every time and have always worked great