Hydraulic Issues - Diagnostic help

[sruman]

I have a Satoh 650 and I have a unique problem that is occurring, and not sure the answer. I've read many many threads, but cannot find a reasonable answer/assistance with my particular issue.

First, my tractor has rear draw bar and a front loader. It has the separate control units for each (rear draw bar is standard, like is on all models). The valve control assembly for the loader may or may not be orginal. Not sure.
The issue is this: When i raise the draw bar (demand fluid), my levers on the loader valve control snap forward, dump and lower the loader. This continues to happen until the bar is raised to the required height. It seems to me (backyard mechanic) that when the bar is raised and demands fluid, it is pulling from the loader control valve assembley, causing the loader to dump and lower. Here are some other facts to help with diagnose the issue:
* Only occurs when bar is raised.
* Loader works fine when used independently.
* Lowering bar has no effect on loader or control valve assembly.
* Fluid levels are good.
* Filter is clean.
* Speed on bar and loader (up and down) are good (good pressure).

Is there a check valve or something in place to prevent this? Can you help pinpoint the issue any further?

Thanks in advance.

Matt in PA.

 

[kennyd]

Matt, I will try to help-but lets get some terminology straight first:

The "drawbar" you are referring to is really the 3 Point Hitch (3PH). A drawbar is fixed, and used to tow wagons and trailers-it's usually a thick metal bar that extends out from under the rear transmission case.

The valve the controls the 3PH is usually called the "rockshaft" lever/valve.

You stated "good pressure", did you test it? If so how?
How many hoses are connected to the valve body that operated the FEL (front end loader)? 6 or 7?
Can you take pictures of how it's (the FEL valve) is plumbed to the tractor?


I suspect that the FEL valve is plumbed in "parallel" with the 3PH, but I am not familier enough with your machine to know for sure yet.

 

[sruman]

Thanks for setting me straight. I'll get the pictures to you tonight.
You are correct. Not a draw bar, but the 3PH "bar".
Good pressure due to the fact that the speed of hydraulics is fine, nothing else. No official pressure testing.

As noted, stay tuned....news at 8.

Thanks.

 

[sruman]

First pic is the FEL controls. There are six hydraulic lines. Two run to the top of the hydraulic "cap" by the rockshaft (pic 2). they other four run to the FEL cylinders.

Question, could the hydraulic "distributor" be clogged or something, causing the draw of fluid from the FEL valve control? Just a thought.

 

[Sonny580]

I dont have a loader on my 650, so I cant be of much help!---sorry! thanks; sonny580

 

[kennyd]

I am not sure what the "distributor" is so I can't help with that. Is this a new problem to has it always done this (at least as long as you've owned)? I am trying to think of how lowering raising the 3PH will trip the FEL valve, so yes I am stalling a bit.

 

[oldnslo]

sruman,
While operating the 3PH and the FEL controls move can you try moving one of the FEL controls to see how force it takes to move them back to center. This might give us a clue.

Also are the handles being pushed away from the valve body or pulled towards the valve body when this happens?

 

[Xfaxman]

I added some labels to the first picture.

What is the "OUT" hose connected to?


Is there a tee connector on either hose from your other valve?

 

[sruman]

See Picture (drawing) attached. This may help us get a clearer picture on the hydraulic system. Pretty basic.
oldnslo: to answer your question, it takes ALOT of force to move them, barely humanly possible. The handles are being pushed toward the front of the tractor (away from driver).

kennyd: The fluid distributor is a "box" that the power steering lines ties to. Nothing more than that (see pic).

By looking at the pick, I think the line 2 (from box B to D) is either clogged, or the distributor (Box B) is clogged. Reason: when I raise the 3PH, rather than fluid come from distributor box (Box B, line #2 on diagram), is it sucking the fluid from FEL Control (Box C). I cannot think of any other reasonable explanation. Again, I'm no mechanic, but it makes logical sense to me. Unless anyone has a better idea, I'm going to tear apart that box and line and make sure they are clean.

 

[sruman]

I added some labels to the first picture.

What is the "OUT" hose connected to?
View attachment 311712

Is there a tee connector on either hose from your other valve?
View attachment 311713

Thanks for the labels. Very nice. Now, both the in and out lines of the FEL control, and connected to the top plate on the 2nd picture, with no tee.

 

[J_J]

If this is an open center hyd system, and the hyd flow is like this. Pump to loader, to 3pt , to tank.

Since all pump fluid flows through all valves, there should be no pressure when the valve levers are in neutral.

The loader spools if working normal, should block all flow to the loader cylinder.

I could see this happening if the loader valve spool is not returning to center so that when you cause the pressure to build by using the 3pt, therefore blocking the fluid, will cause the pressure to build up and affect the loader valve.

Did yo?u make any changes to the hyd lines before this happen

 

[Xfaxman]

See Picture (drawing) attached. This may help us get a clearer picture on the hydraulic system. Pretty basic.
oldnslo: to answer your question, it takes ALOT of force to move them, barely humanly possible. The handles are being pushed toward the front of the tractor (away from driver).

kennyd: The fluid distributor is a "box" that the power steering lines ties to. Nothing more than that (see pic).

By looking at the pick, I think the line 2 (from box B to D) is either clogged, or the distributor (Box B) is clogged. Reason: when I raise the 3PH, rather than fluid come from distributor box (Box B, line #2 on diagram), is it sucking the fluid from FEL Control (Box C). I cannot think of any other reasonable explanation. Again, I'm no mechanic, but it makes logical sense to me. Unless anyone has a better idea, I'm going to tear apart that box and line and make sure they are clean.
View attachment 311714

That is not the way hydraulics work. Your problem is flow is going in the out port of the loader valve, causing the bucket to dump and the lift cylinders to retract. When did this start happening?

My idea is the problem is in the 3PH circuit.

 

[J_J]

It is normal for the 3pt to cause a pressure buildup when the lever is held in the raise position, and the relief valve will sound off, and the relief pressure will back up into any valve upstream and cause problems.

If the up stream valves and spools are working, the loader cyl should not operate with the back pressure. If you try and use the loader with the 3pt lever raised, the back pressure will work against the pump pressure and cause problems in the valve, and possibly blow the seals.

 

[Xfaxman]

If this is an open center hyd system, and the hyd flow is like this. Pump to loader, to 3pt , to tank.

J.J., in his drawing the 3pt is before the loader. The plate on the 3pt reminds me of the old Massey Ferguson system for adding a cylinder. You had to lock the lift arms to use it.

 

[Xfaxman]

I have a Satoh 650 and I have a unique problem that is occurring, and not sure the answer. I've read many many threads, but cannot find a reasonable answer/assistance with my particular issue.

Thanks in advance.

Matt in PA.

Please answer our questions.

Did it ever work right?

Did you make any changes to the hyd lines before this happened?

 

[J_J]

J.J., in his drawing the 3pt is before the loader. The plate on the 3pt reminds me of the old Massey Ferguson system for adding a cylinder. You had to lock the lift arms to use it.

On most tractors, without loaders, the pump fluid goes to the 3pt, and there is some kind of distribution unit somewhere, similar to the Kubota hyd block.

When a loader is mounted, the fluid is now routed to the loader first and back to the hyd block, and then to the 3pt.

He could easily take a hose off and verify the flow path.

A hyd gage would help with the troubleshooting.

It is just not logical to have to raise the 3pt when you want to use the loader.

Which relief valve has priority, 3pt or loader?




.

 

[sruman]

1. They never worked since I bought it (3 yrs ago). Just now getting around the trouble shooting.
2. I did not make any adjustments or mess with the Hydraulics.
3. I think I have a bigger problem now. I have coolant running out of my oil pan seal. I'm going to go out on a limb, and say this is not good, and the engine is now junk.

Anyone need a used Satoh that needs a new engine? Where could you even pick up an engine for one? Cost? I'm thinking that it's not worth fixing, and probably need to just part it out. There are many new parts and tires that have value.
Thoughts?

 

[Xfaxman]

Anyone need a used Satoh that needs a new engine? Where could you even pick up an engine for one? Cost? I'm thinking that it's not worth fixing, and probably need to just part it out. There are many new parts and tires that have value.
Thoughts?

I think you should start a new thread in this forum about the leak, and if you want to sell it, list it here: Private Party Ads, and on craigslist.