New here with a JD 990 and 430 loader

Tailgater · Dec 5, 2007

Hello everyone,
My 990 is about 4 years old. Even when it was new the bucket would drop both under load and without load. I tried to get it fixed under warranty but there was a misunderstanding about the loader being a 1 year warranty and the tractor being a 2 year warranty.

Anyway, I finally got around to setting the loader off the tractor expecting it to leak down since the local JD dealer said that the problem was a bad O ring in the cylinder(s). Lo and behold it did not leak down. That makes me think that it was not the loader but the SCV valve on the tractor.

When it drops, it does not roll the bucket. It just drops straight down. Does anyone have any ideas where I should look for the problem and maybe how to fix it?

Thanks for your help,
Bill
Kingsport, TN

Wayne County Hose · Dec 5, 2007

Hello Bill and welcome to TBN.

More often than not, the problem is a piston seal inside the cylinder. Sometimes they will roll over and roll back, meaning sometimes they will drift, sometimes not. As a matter of fact, whenever someone comes into my shop and tells me of this problem, I tell them they have bad cylinder seals. After I reseal and test their cylinders, their drifting problem goes away and never comes back. Very rarely cylinder drift will be caused by debris in a valve, but this is extremely rare. I can give you a way to test for cylinder drift if you like, but I would just have the cylinders resealed. Let us know how you do. Andy.