control valve??? (I dont even know if that the right name for it)

[2LateIWon]

I have a Challenger MT275 with a Nimco control valve
type 25-40394
date 03-30
serial# 225148

It was leaking where the cable from your joystick goes to the hydraulic valve block. I took out the cable and there was a white nylon washer that looked like it was crushed and a loose fitting oring under that. I bought the closest nylon washer I could find. It fits perfect the only difference is that it is a split washer. So I put new oring on then the split nylon oring. put everything back and noticed it wouldn't seat all the way down. So I tightened it down (but not over tightening it) hooked everything up and I could get it to raise the loader but not lower it. The best it would do would release some presser and it would lower but no down force. So I undid it several times with no luck. Whats the deal???
Thanks in advance!!!

Heres a vid of before I tried to fix it. Just trying to get info and no would commented. So I dove in head first (I think the pool was a little shallow so I'm coming to experts now!!!:thumbsup
You can fast forward to 8:28
[ame=http://www.youtube.com/watch?v=PBkfd9BE6EM]MT275 updates - YouTube[/ame]

 

[2LateIWon]

Still needing help any suggestions?

 

[J_J]

If you don't have full range on the spool, up and dn, then something is binding. It is probably a spring center spool, and should spring back to center with no hands on lever.

There are detents on some spools for float or lock the spool open. You can't just put any washer or o-ring on a spool and expect it to work. Check the bottom of the spools under the caps for water damage, such as rust, broken springs, etc.

There are springs to keep the spool centered, and there are springs and balls, under the caps, so be careful and watch for things flying out.

 

[2LateIWon]

I know I didn't loose anything when taking it apart. I was extremely careful when taking it apart. I've looked for the break down of the control valve and cant find it anywhere. I called Caterpillar and they said they cant find the break down either they have to call AGCO and they are closed until the 2nd So hopefully after I get that break down I can see exactly what it needs with a parts list.

 

[2LateIWon]

So I got someone to email me the break down but I cant talk to anyone yet. Anyways here in the break down I dont see any orings ARGHHH!!!!

 

[J_J]

Some valves have o-rings, and some do not. If your old spool was leaking, then it is probably worn. How much it leaks and when to replace is up to you as far as drops per minutes. etc.

This valve is for reference only, It has o-rings.

http://www.princehyd.com/Portals/0/products/valves/LVManual.pdf

 

[2LateIWon]

Are you kidding me your saying I need to buy a new spool valve if it's not supposed to have o-rings? CRAP!!!!

Thanks for the info.

I know with out the oring it just pours out with the new oring it doesnt leak but I cant move the joystick:confused2:

 

[J_J]

Will the spool move up and down with out the o-ring in place.

If it is not the correct o-ring, and not the correct sealing washer, you might expect trouble.

No, I am not telling you to get a new valve, that is up to you. I would try and fix it first, and if not fixable then I would purhase a new and better valve.

 

[2LateIWon]

I'll have to mess around with it again to see if I can figure it out. Now that everyone is back from vacation and holidays I'm going to try to get ahold of Caterpillar, Agco, and Nimco Controls.

If all else fails and I do need to get a new one what do you recommend?

Thanks JJ!! I appreciate your help and knowledge

 

[J_J]

Here is one that a lot of people seem to favor. It has everything you need on a loader valve. Float, regen, and PB. First valve is a 10 GPM valve.

Surplus Center - 2 SPOOL COMPACT 10 GPM JOYSTICK CONTROL VALVE

25 GPM valve

Surplus Center - 2 SPOOL 25 GPM JOYSTICK LOADER CONTROL VALVE