Repair of Nimco FEL valve

DiskDoctr · Mar 9, 2010

Some of you have read of my troubles with my Mahindra FEL that uses an older Nimco CV112 valve. Here is what I did to repair it.

First, here is a before picture during disassembly. The trick to disassembly is to lift the curl spool all the way up and push the lift spool all the way down, then twist it a bit. If anyone needs more info on this, just ask.

Here is another pic of the problem, notice the flat side of the ballstud, where I drew the red line as comparison. I believe this wear was accelerated by rust. I didn't know the boot was leaking like crazy and the mechanism rusted and became very stiff. I threw some grease at it to make it work, which is what you see in the pics.

You can't really see it, but the socket this ballstud goes into is open on the bottom. Without a pin or anything, the body of the mechanism lifts off the ballstud, which causes sometimes unpredictable combination of curl/lift movements. (This is the fixed anchor used as the pivot point for the lever)

So I ordered a new ballstud. Mahindra lists the steel one at $38. I ordered a 316 stainless steel one from Grainger for less than $10. Even with their minimum shipping charge of $5, it was a deal. The steel one was $1.70, so I splurged a bit to avoid the rust and wear.

The ballstud is 13mm head, 5/16"-18 threaded stud. I turned the stud down on the lathe to 1/4" and threaded it to 20 TPI (standard for 1/4" bolts).

Here is a comparison of the new boltstud and the old one. Note the thickness difference of the nut portion. I also turned this down so the fit (depth) in the socket would be the same. I made the turned down part just a bit over 1/4" to act as a shoulder in the hole of the anchor point on the valve.

DiskDoctr · Mar 9, 2010

An interesting note about the old ballstud- it isn't threaded all the way and the nut would run up against the unthreaded section when I tried to tighten it. I had added some washers to take up that space before this repair.

Here is a pic of my lathe while turning down the nut portion of the ballstud. This was done before making the new threads. Notice I didn't take the old threads quite down to nothing, as I had to leave a little material for the new threads to be correct.
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I tapered the end of the bolt a little to get the die to start. I used the lathe chuck to hold the ballstud and used a hand die 1/4"-20 to make the threads.

Here is a pic of an 1/8" pin I chose to put in the body of the valve mechanism. I've drawn a red line on the final pic to approximate where it goes. It holds the ballstud in the socket.

This "pin" is actually a roller pin out of a taper bearing I found laying around in the garage. I cut it off to length and put a small taper on the end with the lathe to facilitate installation.

I drilled 1/8" hole where I thought it should be, and guess Nimco agreed with my placement. I found the remains of an old pin! I know their newer designs used pins, but didn't know this one did and it was broken and missing

Certainly explains the problems.

The pins were REALLY hard to drill out, but the new one went right in. Here's a pic of the final results.

I also cut off and turned down the handle to add new threads (8mm x 1.25). I couldn't get the handle all the way in, but it may be tapered down in the body. This handle broke off last year just below where a jamb-nut was, so now was the time to fix it up.

Now the movement is GREATLY improved :cool2:

Previously, my curl action would often end up being at about 11 o'clock instead of 9 o'clock. The curl was also weak. I determined a bit ago this was due in part to the lift spool being partially actuated when curling. This was due to the anchor point (the old ballstud) not doing its job.

Now I can't wait to try it out! I recently repaired a suction line leak before the filter (small section of rubber hose), changed the hydraulic filter, and put in new hydraulic fluid, which was also a bit low.

So I have high hopes for this repair. If anyone else is having problems with this valve, perhaps this writeup will help them fix it.

Hope you all enjoyed the writeup.

- JC

B8FISH · Mar 9, 2010

Nice write-up of the procedure! Good pics, too.
Thanks for taking the time to document everything so clearly

DiskDoctr · Mar 10, 2010

B8FISH said:
Nice write-up of the procedure! Good pics, too.
Thanks for taking the time to document everything so clearly

Thanks for the compliment, B8FISH! As you can tell, I ran out of daylight

I expect the needle bearing to be plenty strong, didn't have any 1/8" spring pins. Just hope it stays in place. I considered peening it, but it was late and the fit was tight. We'll see.

- JC

kennyd · Mar 10, 2010

Nice job JC:thumbsup:

DiskDoctr · Mar 10, 2010

Thanks, Kennyd!

I forgot to mention the anchor point has a horizontal recessed (slotted) area where the ballstud fits to keep the stud from turning. It was worn, which let the old one turn when trying to remove.

I think this may have happened prior to the repair when I tried to tighten the anchor and the nut was against the unthreaded shoulder- twisted the stud and rounded these edges.

I dressed the edges with a sharp edged file to restore nice crisp edges.

The nut portion of the new one is a bit larger than the old, so I used a grinder to take a little off two opposite sides until it fit nicely.

I wasn't sure what to use as lubricant. I didn't have grease in the basement, but did have teflon pipe dope, so I put some of that in the ball/sockets. I don't know if it is any good for this, but it's basically waterproof, sticks where you put it, and has teflon in it. With my luck, it will probably get wet and harden into cement (!)

FYI. Here is the valve number/info: 10373-2s

- JC

DiskDoctr · Feb 22, 2011

Update.

It's been almost a year and I've been using and abusing this joystick since the above repairs.

It's doing quite well and I haven't noticed any change or degradation.

Looking back, it was more effort figuring out and sourcing the ballstud than doing the actual repair.

If you have a similar problem with this model joystick, you should be able to repair it for < $20 and a little time in one eve.

Sure beats buying a new joystick!

- JC