Sickle Bar Changing a JD 350 sickle mower from wide to narrow

[Casa Del Paca]

I really didn't expect that this would be such a challange but it is. So, if anyond has any experience with the JD 350 sickle mower, please let me know. First, I have to change (reverse) the two bars that attach to the draw bar. They each sleeve over a 3/4 to 1 inch pin with two washers and a hollow pin (hollow pin goes through the 1 inch pin) to hold it in place. Here's the question, how do I get that **** hollow pin out? Do I hammer it out, do I drill it out, will it have to be replaced and if so, what is it called? I got the owners manual and it says that I have to change many things to make it fit my tractor. Unfortunately, it doesn't give much explaination as to how to change these things. If you have some experience, please let me know.

Also, there is a chain that (I believe) raises the sickle arm or at the least, sets the angle for the cut (not the one that goes through the spring but the other or are they the same chain?). Can anyone tell me what size that chain is supposed to be? The one on my mower is welded together in one spot and bolted together in another. I guess that it would be best to replace this mess but I don't know what to get. If there is anyone with a parts manual, let me know if I should just order one of those too.

It's just a sickle mower, it's not supposed to be this tough! Thanks in advance to anyone that can help!

Mark

 

[TravisTractor]

pic's would help, not to experinanced with 350 but i am with the older one's. i am not clear on the hollow pins

 

[Farmerford]

Those pins that hold the lift mechanism are spring pins; 1/4 inch by 2 inch, I think. They have to come out to remove the lift bar, after you have unbolted the two halves of the lift bar where the chain attaches. They are usually hardened, so it is better to drive them out that drill them. They are not really necessary (at least on my 350's) because the bar holds itself in place once the two halves are bolted back together.

As for the chain, there is only one; I think it is a short link 3/8 chain, but any chain will do; if you use a regular length link the link counts in the manual will not be correct. The chain runs from the hook/bracket at the rear of the lift bar, down to the sheave (pulley) and then to the hook on the left end of the large spring, then it continues through the large spring to the hook on the right end, and from there to the upright hinged arm on the wobble drive head. The spring is under tension except when the cutter bar is about 45 degrees above the ground. That tension does two things: (1) applies lift to the inboard end of the cutter bar, where the drive head is, and (2) it applies lift to the outboard end of the cutter bar, where the head board is. The balance between the lift on the drive head end and the head board end is determined by where the chain is attached to the upright hinged arm on the drive head. The total lift is determined by the number of links of chain between the inboard spring hook and the lift bar, and the number of links of chain between the outboard spring hook and the arm on the drive head. I think that is spelled out in the manual, but if I recall I had to fine tune mine by shifting a couple of links.

The part of the chain inside the spring is loose when the spring is not under tension. The purpose of that chain is to keep the spring from overstretching when the cutter bar is raised.

When everything is set just right (and that takes patience and trial and error), when the lift is dropped so the cutter bar is down, it will easily slide along the grass because the spring takes a little weight off both ends of the bar; when the lift is raised the outer end of the cutter bar raises 2 to 3 feet off the ground, but the drive head end stays on the grass.

Finally, when the cutterbar is in the stored position, and the lift is up, the spring has enough tension to lift the entire drive head and cutter bar assembly off the ground a little bit so you can go to and from the pasture.

It really is a pain to set up, but once you figure it out is works pretty well.

Send pictures.

 

[whirly]

The spring/roll pins are driven out with a punch or drift pin. You also have to move the Pivot Shaft (below the PTO) to the other taper hole on the hitch frame - Left for narrow and Right for wide. Additionally, you will need to move the Pullbar to the appropriate position -N or W as marked on the mower.

Sorting out the chain on the lift arm will be done once the mower is set up and attached to your tractor as Mark explained above.