Rebuild a 16LA front end loader valve ?

[GATC35]

Anybody have any experience with this ? My bucket curl is bypassing. When I try to back drag the bucket swivels up. Swapped the hydraulic hoses between the boom and bucket curl and the problem went the the boom circuit. So it looks like my control valve needs seals, seats, springs etc.

Any info. we be appreciated.

Mark in Georgia

 

[JerryG]

Does it clear up for a bit if you work the bucket up and down without anything in it a few times?

 

[Soundguy]

I hope they are more rebuildable than the remote pack spools are...

soundguy

 

[jinman]

Mark, it sounds like you've isolated the problem. Does the bucket hold a load without dumping it? It sounds like it is only in the curl-down pressure side.

Are you going to work on it yourself? If so, there are two check valves you might check before tearing the valve body apart. They are located on top of the loader control. They both have hex-heads (not allen heads) and may have a piece of trash in one of them or the spring may be broken. Other than that, I don't know anyway you can avoid taking the valve apart. Good luck!

 

[MadReferee]

If one of the load checks was bad then you would see the motion as being jerky. The load check only comes into play the instant the spool is activated and it simply holds the cylinders in place, thus overcoming the effects of gravity, until pressure builds up in the activated spool curcuit. This is pretty much in the blink of an eye time frame.

 

[GATC35]

JerryG; If I cycled the bucket stop to stop several times it gets better but does not completely solve the problem. Increasing engine RPM also helps but does not elminate the problem either. Problem is always worse when it's cold, the first several cycles.

jinman; Yep..I plan to try it myself. The service folks at the local NH dealer are pretty good about helping me out. I took the black plastic cover off the valve last night. It was dark and I didn't have a good flash light to look the valve over. I do remember seeing the large hex head nut on top of the valve.

mad; The first one or two cycles of the day are jerky. Then it smooths out and moves smooth. Even after it's warmed up good it will bypass while trying to back drag.

Thanks.. to all I'll keep you posted on what I find.

 

[JerryG]

Have you checked your fluid to see if it has bubbles in it? Very small little bubbles.

 

[jinman]

jinman; Yep..I plan to try it myself. The service folks at the local NH dealer are pretty good about helping me out.

Do you have a repair manual? If you need help with that, please PM me with your email and I will get you some diagrams and system operational descriptions.

I think the checkvalves I mentioned are not a single large hex-head, but rather two hex-heads in the 14-16 mm range. I said on top of the valve, but the way it is mounted, they are on the front of the valve I believe. Here is a link to Messicks.com. Scrool down until you see the Hydraulic System and then look for the two-spool remote control valve. There are two illustrations. The first drawing shows the mounting details and the next one shows all the internal spools, seals, springs, checkvalves, etc. The second one will probably be your best source for repair part numbers.

Two-spool Remote Control Valve

 

[newt]

Thanks for the link. I have read most of your postings ,but this is a big help thanks.

 

[Dave_S]

What does the Very small little bubbles, mean?

Dave