Hydraulic Spool Rod super tight

It is odd that the email notification of your post shows the text you wrote, but when I come to this page to reply I can not see what you wrote. I will include it here for reference:

Fastdriving wrote:

I am unable to turn my hydraulic spool rod in any direction 
and my 3 point is stuck in the up position. Super strange 
that I unloaded my snowblower from the three point and the 
three point was working just fine. I then attached my 3 point
 grading blade and move it to the up position, to where it 
sits now. I also have a hard steering issue going on. Related? I am looking for some pointers.


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Ok, now some questions:

What make, model and year of tractor do you have?

I am unsure what you are referring to as “hydraulic spool rod”.  This is a term I have never heard used before. Most hydraulic control valves have a spool inside them that slides and are sometimes called a spool valve. The spool itself is free to rotate in the bore, but there is no way to “turn” them. Typically any rod that is associated with a hydraulic valve is just a link rod between the control lever and the valve mechanism. Can you be more specific about exactly what you are referring too? Perhaps post a picture?

From your description, it seems like you removed the snow blower and attached the blade. Then you were able to use the 3 point to lift the blade but now it will not come down. Is that correct?

Did the hard steering start after the blade got stuck or before?

Are there any strange noises from the hydraulic system, specifically a squeal or groan from the pump?

Do you have a front end loader on the tractor?

Do you have a single hydraulic system with only one pump that runs everything, or does the power steering have its own separate system?

If you have a Jinma tractor or one made by them it is highly likely that there is a needle valve for controlling the lowering of the 3 point. This is usually located under the front of the seat. It will have a scalloped knob that you can turn to adjust. There is likely a screw on the front of the housing that is used to lock the knob once it is adjusted. This knob will not turn until you loosen the lock screw. The purpose of the adjuster knob is to close or open the needle valve, which in turn controls how fast the 3 point system will lower. If you have something heavy on the 3 point lift it can “slam” down rather hard if the needle is too far open. The opposite is true if you have something light weight (or nothing at all) on the arms, it might take a very long time to lower if the valve is too far closed.

This valve only controls how fast the arms lower, not how fast they go up. It can also be used to “lock” the arms to prevent them from lowering by trapping the fluid in the cylinder. You can add more fluid to raise it more, but it can’t come down until the needle valve is opened.  This can be a real problem if you lift something up all the way and the valve is closed, The internal pressure can make it really hard to open the needle valve.

My point of reference for all this is my Jinma 284 made in 2006. It has one hydraulic system that runs the power steering, 3 point lift and the front end loader when it is mounted and connected. There is also a priority (diverter) valve that gives priority to the steering system whenever you are using the FEL or the 3 point. This valve sits between the steering and 3 point and it can cause problems for both, but usually not the problem of the 3 point being stuck all the way up.

If it were me diagnosing this, I would lower the FEL (if mounted), put the 3 point control lever in the “down” position (it will stay there) and shut off the tractor. Put any additional weight you can on the blade and let it sit overnight in the hopes that it will slowly bleed down.

If it does, great, adjust the needle valve and move on (don’t forget the lock screw). If it does not bleed down, I would loosen the needle valve, by force with some big pliers if needed. Be careful here, because if it is under pressure when it does come loose it can blow fluid everywhere! There could be debris in the needle valve that is preventing it from releasing so be prepared to take it all the way out. It will be messy! Best done when the fluid is not hot.

Steering should have nearly equal flow both directions.

It is starting to sound like you have some debris in the system.

When was the last time you cleaned the pickup screen (or filter if equipped) and or changed fluid?

Have you checked the fluid level?

My 284 only holds a little over 2 gallons which really isn’t enough when the FEL is mounted and the hydraulics start acting up if the level gets down very far.

Ok, good. Now I know where you are coming from. What you have done so far is all good.

As for the 3 pt. lift cylinder. It is just a one way cylinder (no down pressure) but it does have two fluid ports. One port lets in fluid from the control valve when you pull up on the lever. The other port is the one that flows through the needle valve and then back through the control valve when the lever is in the down position.

The locking screw is on the front face of the housing and on mine at least it is just a slotted pan head screw. If it gets turned in to tight it can mess up the threads on the knob and make it difficult to turn.

You might be able to relieve the pressure in the cylinder by putting the lever in the up position (engine off of course) and manipulating any of the other hydraulic controls. There may be a check valve in the control valve that would keep fluid from flowing backward, I am not sure about that, but it won’t hurt to try.

Just now looking at the parts diagram, I see that Jinma does indeed call the needle valve a hydraulic spool rod. Something must have been lost in the translation, Ha!

Anyway, that valve screws into the end of the cylinder block and there are some caps that are also screwed into that block. You might try cracking those caps to see if it will let off the pressure. If you don’t have a parts book, you can see it here:

https://www.circlegtractorparts.com/hydraulic-power-lift-18-28hp-tractors

IF the exit port is blocked by debris, you may have no choice other than to remove the entire block to clean it out. If you didn’t find much crud in the pickup screen, I would leave this as a last resort kind of thing.

There just isn’t much information about the internal workings of these valves as there are no internal parts available so you have to buy the whole thing. That doesn’t mean you can’t take them apart and clean them.

The power steering is probably not related at all to the 3 point issue. About the only two things that can cause steering problems are the steering box and the priority valve. The fact that you have good flow in one direction but not the other would kind of rule out the priority valve, leaving the steering box at the bottom of the column as the prime suspect. There have been reports of these going bad and I think the only alternative is to replace it.

How many hours do you have on your tractor? I have almost 1100 on mine and have not had any hydraulic issues other than hoses and seals at fittings. Although I have one FEL lift cylinder that is starting to leak. I am using the FEL daily at this point and don’t want to sacrifice good weather with down time so I just keep the tank topped off.

Hopefully you can get some fluid out of one of those plugs and get it working again. Let me know what happens or if you have any more questions.

glad to read that you were able to relieve the system without alot of disassembly.

Good thinking. Glad you got it working.

after you found out how to release the pressure on the lift did the steering issue remain or did it straighten it self out too??