JD #30 square bale thrower

Hey guys,

Just learned another lesson in the school of hard knocks (pun intended!). We have used balers with these throwers for decades and just learned another lesson in maintenance. The hydraulic cylinder which activates the thrower pan blew apart by hyper extending while throwing a bale. JD wants $633 for the special cylinder. I had never given any thought to what is inside the cylinder, just took it for granted. Well here's the scoop... The bottom half has a large coil spring arranged to cushion the thrower pan at the top of its throw stroke. This spring is coated in grease to keep it from scraping up the rod and barrel. There is NO hydraulic fluid in this chamber. It is easily accessible by removing the 6 bolts on the lower flange. It is a very husky spring, but retained by a short rod and end plug. No danger in removing the flange bolts. Our spring was broken into 6 sections of coil, meaning that it was not effectively cushioning the throw, so the impact of the throw at the top of cycle eventually led to metal fatigue and cylinder failure on the hydraulic side. JD has the spring for about $33.

The hydraulic side with 2 ports located at the center of the cylinder has a strange "push only" chromed cylinder rod which is quite robust. But instead of having an end puck with O rings, it merely has a single snap ring at the end of the rod. There are 2 sets of strange grooves for the snap ring. During reassembly the cylinder end seals are put on the chrome ram and then the snap ring is put into the groove closest to the clevis end of the rod. Then the rod and seals are pushed into the cylinder bore and now get this... Reach through the bigger cylinder hose hole and use a tool to move the snap ring to the groove closest to the bottom end of the ram. The snap ring keeps the ram from hyper extending.

Who woulda ever guessed all this from a simple looking hydraulic cylinder?????? I am amazed that it lasted as long as it did. Our other 2 balers with #30 and #40 throwers will get their springs inspected and replaced as necessary. I did find another used cylinder on a junk baler, cost less than $100, but had water in the hydraulic side. If its not usable as is, then it has enough good parts to put the blown one back in service.

Inspect your hidden spring and possibly save a lot of down time and $$$.

Paul in MN

The spring does cushion the mechanism at the end of the stroke, but it also throws the pan back to the home position. Usual failure is evident by failure of the pan to latch at home. Instead the pan will "wave" at you.

WOW!!!!!!!

Who would have thought.

I keep telling myself that one of the reasons to own a JD baler is the wealth of tribal knowledge that exists for these balers. More experience shared with the user community.

Thanks!
Bill

Roger,

I expected that the spring did help in returning the pan to "park" position, but in this case we had no trouble throwing (and returning), and had just completed 1,000 bales with this baler. I can't believe that the spring broke into 6 pieces on just that last bale. So I do agree with you about the spring's function, but this time the baler just continued to work properly and continued to throw the bales the same predictable distance as per the number dial. Like I said, just another lesson learned. Thanks for your reply.

Paul in MN