B1550 3-point control valve

[treefarmer1]

I have a 1991 B1550 - Hyd -4wd with 3397 hours. I put on 3297 of those hours. The 3-point control valve is not functioning correctly. It will not hold the setting and lift arms drop. I was told by my local dealer that replacement parts were no longer available. Any suggestions? Can an external pump be installed? I am not ready to give up on this tractor.

 

[North Idaho Wolfman]

After your dealer made the statement "replacement parts were no longer available" did he follow that up by saying, but I can sell you this new model!

That is such a dealer cop out answer!
What he really should have told you was:
"I'm sorry but our dealership has mechanics are too stupid to fix it"
or
" We really don't care about you $100 repair we would rather you buy a $40,000 new model"

I'll move on to the point, It's fixable with new or used parts!
It's probably not the pump, it's probably the valve or lift piston that the problem.

First lets start with the basics.
Any add on valves or loader?
Lifts or not?
Lifts load or not?
Lifts and slowly drops when running?
Lifts and slowly drops when parked?
Any noise?
Any leaks?
Better cold?
Better warm?
All details will help pin point next route to go.
Details on what happening and what's not.

There is more trouble shouting steps but lets start here.

 

[treefarmer1]

In response to your questions:

First lets start with the basics.
Any add on valves or loader? No.
Lifts or not? Yes, no problem.
Lifts load or not? Yes, no problem.
Lifts and slowly drops when running? Yes. Actually it is pretty fast.
Lifts and slowly drops when parked? Yes.
Any noise? There is a little noise, but it is intermittent.
Any leaks? None found.
Better cold? No difference.
Better warm? No difference.

It wasn't something gradual, seemed to happen overnight. I just thought the lever needed adjustment. What else can I check?

 

[North Idaho Wolfman]

#1 thing I would check for is a broken, bent or disconnected feed back link.

 

[treefarmer1]

I will move it to the garage where it is warmer to work on. Temps down around 10F with significant snow forecast over the weekend. Based upon the schematic it appears I will need to tear this thing open. Not real confident I have the skills or tools needed.

 

[D2Cat]

Before you remove any parts, I think Wolfman was suggesting to only look at the parts highlighted in yellow to determine they are all connected as shown. Not bent, disconnected or broken.

 

[treefarmer1]

Understood, thanks. I did check the linkage and everything seems to work properly. Nothing bent, disconnected or broken. I contacted another dealer and they indicated parts were available and they thought it could be fixed. The labor rate and time is what drives the cost obviously. Used it this weekend to plow snow and drag culled trees. Just inconvenient to keep holding the lever up when moving snow. Any other thoughts before I call the second dealer to come pick it up? I appreciate the advice.

 

[whitetiger]

Try to tighten the nut at the bottom of your 3pt lever, that is where your friction washers are located. I run into this several times a year and it usually is just the nut has come loose.