Loader Control Problem

[jinman]

John, I just thought of one more thing (two actually). The two check valves shown in the diagram below (items 17-20) are what hold pressure while the joystick is in neutral. If something got trashed in the spool valve or trash got into the area, one or both of these check valves could have foreign material and not be sealing properly. They are a pain to get to because they are on the front of your loader valve as it is oriented on your tractor with two hard lines right over the top of them connected to 90 degree fittings. Even so, it might be worth pulling those lines and checking these valves for trash if you have not done that.



This photo shows the two lines in place, but I have my platform raised up and it is blocking the view of the entire area.

 

[RDrancher]

I had a little more time this morning to read the pages Jim posted and think about what the spool is doing.

Now I'm sure that the spool is not traveling far enough to get to what Kim called the "quick dump", or second joystick position. Is this what is referred to as "regen" ? Or is regen what happens after I "quick dump" and "reset" the joystick to apply bucket pressure?

When I had the piston sleeve off, I noticed that there is a machined ridge inside the sleeve that keeps the piston from overtraveling. I think that the forcing of the joystick too far to the right (over and over by the gorilla guy) actually overcame the dentent balls ability to "squeeze" on the ramp part of the piston and then allowed the piston to be pushed past the ridge in the sleeve. When the cap (which is the last stop for the piston and had piston marks on it) loosened up, it allowed the detent balls to drop behind the piston and rest against the piston spring/shaft. The piston couldn't return and it all quit working.

Now that I think of it, the ridge inside the sleeve isn't centered in the bore. There's a short and long end. I may have it in backwards which would definately limit the stroke / travel of the spool.

I'll let you know what I find. Thanks for the brainstorming guys!

 

[RDrancher]

Sorry Jim, I just noticed we were on page three. The check valves are something I will for sure look at, especially with the one detent ball missing (or pieces of?). I'm going to take the entire valve off again tomorrow morning when it's cooler out, so we'll see.

When I removed the spool cover the first time, the piston, spring and at least one of the detent balls came out the end. The piston should have been limited by the ridge inside the sleeve. It was obviously past it.

 

[jinman]

John, I have full confidence that you'll be able to find your problem. Your problem resolution skills are at least as good as mine if you have the right info. I'd offer to help, but I'm still recovering form surgery and trying to limit my activities. I don't think I could be anything more than moral support at this point anyhow. If your valve can be fixed, I'm sure you'll do it.

 

[KWentling]

Regen would be when you are dumping with the lever in the furthest position. Are there any quick couples between the valve and the bucket cylinders that may be partially uncoupled or defective? Have you swapped hoses to see if the problem follows the function? You should be able to determine if it is the valve, cylinder (doubtful) or plumbing problem. If there are quick couples involved I would check them out first.

Kim

 

[J_J]

I have to ask, are all the parts back in the valve?

Did you or someone else maybe switch parts? Did you have both spools out at the same time?

That regen part is a soft detent, which lets the operator know when he is in regen, not like the float detent, which is a snap and hold situation..

Have you removed parts 17,18,19,20, which is the load checks to check for debris? I mentioned the load checks back in post 13.

Which end cap had loose parts in it when you removed the cap, the float spool or the regen spool.

I am thinking your employee thought the regen should stay in detent and therefore tried without success to jam it to far many times and is now causing you trouble.

 

[RDrancher]

First, to answer questions.

No parts were swapped between float and regen spools.

The regen spool had the loose parts in it.

The float spool operates fine.

Removed and checked 17-20. - No debris and springs, poppets look fine.

Removed the entire valve again from the tractor.

Removed end cap. - All looks as it should.

Removed the outer spacer 13, regen detent sleeve 4, detent balls 8, piston 6 (poppet) and spring 7.

I DID have the detent sleeve in the correct position, so I can rule that out.

With these removed (nothing to restrict travel), the regen spool moves smoothly and freely and with a lot of travel (more than what it would normally move during operation.)

Checked both detent balls with a caliper and they're both the same.

I checked the tightness of the detent retainer 9. I got a full turn+ before it was tight on the end of the spool. Hmmmmm...

With the valve back together and still on the bench, it seems as if the spool is now traveling slightly more than it was before tightening the retainer. I have about a 1/4" travel looking at the top of the shaft. This looks to be about a 1/16" more than before I took it apart. Ii can't feel any difference in the joystick, but probably shouldn't since its a "soft" detent?

I'm not positive about this...but I think that the piston 6 needs to travel far enough for the detent balls to ride up the piston ramp onto the flat spot of the piston for it to get into regen. The way my mind is wrapping around it, tightening the detent retainer should help. Of course...I could be wrong and its completely out of adjustment now.

I'll put it back together and see.

 

[RDrancher]

After putting the valve back in, it functioned perfectly ONE time. The joystick felt better though, and I could actually "lock" the bucket at level and backdrag with it there too. Just couldn't get it to work in any other position other than level.

At this point I dismissed the valve / regen spool as being the problem.

I took off the hyd. disconnects for the bucket and DING DING DING... we have a winner!

The poppet on the male side of one of the disconnect fittings was in there almost sideways. No amount of pushing on it would get it straight. I removed the fitting and found what looks suspiciously like a fragment of detent ball. It had lodged in there and the little clip that aligns the poppet assy had dislodged from its proper spot as well. It looks like the shaft on the poppet is actually bent.

Time for a new disconnect fitting.

Hopefully the rest of the fragments have made it to the filter.

 

[J_J]

The balls are supposed to ride up on the flats.

The QD's were mentioned in post 13 and 25.

A hyd gage would have helped if used.

Glad you got it fixed.

 

[J_J]

The balls are supposed to ride up on the flats.

The QD's were mentioned in post 13 and 25.

A hyd gage would have helped if used.

Glad you got it fixed.