Troubleshoot a Hydraulic Problem for me please!

[ebeb]

(apologize for my undeveloped tractor vocabulary in advance).

New JD 4410.

Had an "aftermarket" grapple attached when I bought it, attaches to top of bucket and runs off of device that raises/lowers mower deck (I am new to this tractor thing, still learning my terms).

Used the grapple the other day, and used it to pick up three nice sized stumps today. When I approached the fourth one the grapple wouldn't shut.

I can get it to move slightly back and forth when I move the scv/lowering device (whatever it is called), but it won't move more than an inch in each direction. I tugged on it while my wife moved the lever, still no luck.

I then switched the hoses back to the mower deck and the levers below raise and lower as they should (deck is unattached).

Backhoe hydraulics working fine, as is FEL.

Hoses for grapple look fine, not pinched anywhere I can see. Strange it would work one minute and then not the next.

Any other suggestions?

Eric

 

[Gatorboy]

Have you checked your fluid level? If it's low, you could see those type of symptoms.

 

[Boiler74]

Eric,

I think I know what your problem is. You've pushed the grapple back too far, and now the piston doesn't have the angle to push it forward. You need to shut the tractor off, then relieve the hydraulic pressure by working the SCV level forward and back. Then jump off and pull the grapple forward. I think I have the same setup as you (ebay grapple?) and it happens once in a while. I've figured out that if I roll the bucket forward and then work the controls, the grapple will usually work because of the added weight of the grapple.

Hope that helps.
Josh

 

[ebeb]

hoosier, I bet you are right as it looks like it more retracted than normal

I will give your fix a try in the morning

Andy (the ebay guy) offered up the same solution.

Thanks again for the recommendation on this thing. Once I get it working perfect I will really thank you.

Eric

 

[Boiler74]

I've adjusted the U-joint at the end of the piston a few times, and making the stroke longer or shorter seems to make the piston more prone to this problem, so you may want to play with that some.

Josh