John Deere 9W Sickle Bar Mower - Adjusting Register

Been having a few setbacks with my new-to-me JD 9W sickle bar mower. I keep breaking pitmans and even a blade. Dad and I have narrowed it down to what we think is the problem. Dad sourced these new-type hold-downs that have a bolt and spring on them that adjust the down pressure they put on the sections. We think we've gotten them too tight. We put on a new pitman arm and loosened those hold-downs a bit, but now the mower is out of register.

Loosened the set screw and bolts on the "adjusting rod", but we can't get the thing to move. More accurately, we were able to move it after a lot of WD-40 and pecking about a 1/4 inch. but now it won't move either way at all. Best we can tell, the mower is out of register by over three times that.

How important is register for overall cutting action? Could it be causing stuff to break, or are we on the right track with those hold-downs?

Here are some pictures for your viewing pleasure:

Broken blade:
mvphoto26582.jpg

Notce the "new-style" hold-down, and how it has worn a shiny spot on the old sections. Too tight?

Broken pitman arm after replacing the blade and adjusting the shims under the hold downs:
mvphoto26583.jpg


Attached to my 841S, just because:
mvphoto26581.jpg
 
It really looks like the sickle sections are worn out. They look DULL. That will break the pitman right now.
 
After breaking the blade with the old sections on it, we put in a new blade with brand-spanking-new sections. That's when the second pitman arm broke (after less than 5 minutes of mowing).
 
I just registered my old mower the other day.
I had to replace the pitman, had to use a blank pitman rod, the broken one was in
pieces.

So I got it close,

on my MF 32 mower you have to remove or add shims to the bar attachment bolts to move
the bar in out as necessary for the fine adjustment.

The blade sections must cover one guard when the cutter blade is in and another guard
when the cutter blade is out. If it stops in between sections as yours appears to do
then your mower is out of register.

Question: why did you get those odd blade hold downs, are they proper for your mower?

It was a bit more expensive, but I always had better luck with MF parts on my old mower.
 
Once rusted in place those sure don't like to move!

Remove the 2 bolts and drive a tapered chisel or two in the open side of the clamp to spread it and release it's rusty grip on the bar.

On the other hand, what are you using for a pitman stick?

You may have the wrong one, or a PO had the wrong one and adjusted register to compensate.

(The correct pitman wood, # H28286, is a little over $30 at the DEERE dealer.)
 
I learned on getting a Ford 515 going well. Not a pitman mower but one of the best money spent
repairs to it was a complete matching set of guards, in turn giving me a consistent height at
the ledger plates. It was either binding or the knife wasn't laying right with the dukes
mixture of guards that were there when I bought it. I found some less expensive aftermarket
guards and have been mowing good ever since. One diagnostic trick I read somewhere, probably
here, was let the mower run at mowing pto speed (540) for several minutes, tractor sitting
still of course. Take your favorite aerosol lube ( wd40, PB blaster, what have you) and shoot
some on the hold downs where they contact the knife........if your spray smokes off from the
heat then your having to force the knife down and it's binding. With the consistent ledger
height I could back off the hold downs and the mower ran much smoother. I want my hold downs
only job to be keeping the knife and the ledgers close when material to cut is entering the
bar.
 
"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]How important is register for overall cutting action?[/i:654c4848f0][/b:654c4848f0]</font>"

If the knife is not in register it will not cut very good and will probably clog and the mower's cutter bar will break away from the pull bar.

Reviewed the [b:654c4848f0]JOHN DEERE 37, 38, and 39 MOWERS PREDELIVERY INSTRUCTIONS PDI-E39953[/b:654c4848f0] under the [b:654c4848f0][i:654c4848f0]REGISTERING KNIFE[/i:654c4848f0][/b:654c4848f0] topic on page 17.

"[b:654c4848f0][i:654c4848f0]To insure smooth cutting and light draft, the knife must be in proper register. The knife is in register when each knife section is the same distance beyond the guard at the inner end of the stroke as it is at the outer end of the stroke.

Be sure pitman is attached to knife, the cutter bar is lowed to cutting position, and the mower is level. Rotate pitman by hand and at the outer and inner ends of the stroke, note the position of knife sections in relation to the guards. If the center of the section is not an equal distance beyond the center of the guard at the extreme end of each stroke, the knife is out of register.

To make registering adjustment, loosen two nuts on clamp bolts and loosen lock nut and set screw in pivot casting until knife is in register. To accomplish this, it may be necessary to tap lightly on the appropriate side of pivot casting with a hammer.

Tighten set screw and lock with nut.[/i:654c4848f0][/b:654c4848f0]"

Basically the tip of the section needs to be centered in the tip of one guard on the out stroke and centered in the tip of another guard on the in stroke.

Take a look at the pivot and drag bar in the photo below.

a199310.jpg" width="650"


You might consider using a block of wood and small hammer to move the pivot.

"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]Could it be causing stuff to break, or are we on the right track with those hold-downs?[/i:654c4848f0][/b:654c4848f0]</font>"

The knife being out of register probably is not the primary cause of a broken knife or a broken pitman.

It has been my experience that a broken knife can be caused by too much vertical stress on the knife head.

Take a look at the diagram below.

a199311.jpg" width="650"


Note the inner shoe (Key 41), the plate (Key 40), front guide (Key 2), rear guide (Key 3), guide shims (Key 4-5), guide plate (Key 6), wearing plate (Key 7), and plow bolt (Key 8).

Take a look at the photos below of the inner shoe.

a199314.jpg" width="650"


a199313.jpg" width="650"


Make sure the plate, displayed in the above photo, is in good condition.

Remove any other "farmer tech" plates, shims, washers, spacers, bolts, etc. that are not OEM (Original Equipment Manufacture) parts.

Take a look at the photo below of the front guide and rear guide.

a199315.jpg" width="650"


With all the correct, OEM parts installed, the knife head should move level freely and unrestricted on the inner shoe.

You might consider using lock nuts on the plow bolts and get them really tight so that the cutter bar does not "pivot" on the inner shoe.

This is a good first step to eliminate the knife head from breaking.

You might also consider setting the height of the inner sole and outer sole so that the cutter bar is somewhat the same distance from the "level" ground on both ends.

Check the spring tension so that the inner shoe "float" does not put additional stress on the cutter bar.

Hope this helps and good luck with your mower.
 
Once you get the blade in the mower you should be able to slide it back and forth easily by hand if not something is binding and you're going to have problems.Way better to have hold downs a little loose rather than too tight.Also the sections in that picture look like they have been run way more than 5 minutes.Personally since good belt driven mowers are around at reasonable prices I wouldn't spend 5 minutes working on a pitman mower that's not going to be but so good if it works like new.
 
The only mowers I ever had, from horse drawn to semi-mount, fully mount and pto drawn. several I dont remember ever being a register adjustment, just the lead of the bar that has to be correct before you can adjust the register and the only way to adjust the register was by making sure you had the correct pitman. I have never had a pitman break, replaced some due to rot but never had one break. I bought my first mower back when I was 16, a horse drawn Deere but had been mowing with Dads David Bradley horse drawn before that, an just about to turn 72 now. If you do not have that cutter bar lead correctly then you will never get the register correct. And broken blades come fron several reasons including bad (wrong, broken or wore out guards), including missing ledjer plates, wore or missing wear plates under back side of knife wore out hold downs, if the hold down is too tight then knife may not be able to be moved at all as it should slide with ease. When you replaced the pitman what kind of wood did you use? Wrong kind will not last.
 
JD seller is correct. Your sections are worn out. That will cause breakage of the sickle as your picture shows and breakage of the pitman stick. You need a new complete sickle. Get the ones with Chromed sections not regular ones. The chromed last longer, are tougher to break and for me stay sharp longer.
 
I set the mower down one day, do not remember for sure but as I set it down ready to mow,

There was something hidden in the grass, short stump or rock, the pitman hit the rock and broke into pieces.

Therefore I did not have the old one to go by to insure I got it the same length, that is how I got it out of register.

Old friend of mine who raise cattle all his life, was looking at it one day, I turned the pto shaft to show him how smooth it ran.

First words out of his mouth, you are lucky this mower will cut anything, it's out of register.

He expanded what that was, I had to get my manual out to review "Register"

He was right, it expanded how to register the blade, I had to get my buddy to come over and help me as we had to take a number of part loose and move shims around.

I too had never heard of register, it cuts much better after registering the blade.

Guess it's somewhat like tuning up and old car or tractor, after you install the points, etc, you need to check the timing.
 
A sharp sickle is a MUST. A matching set of guards is almost as important. Timing or setting the register is CRUCIAL!!!! I am with
you on having your hold downs to tight. Mine don't leave any marks on the sections. I also wear my sickles down a WHOLE bunch more
then yours, but I sharpen them after 4 hours of mowing!! A 4 or 5 inch hand grinder works, but I have an antique Shadle sharpener
that does a better job. PTO speed is also important. If you start hearing a loud chattering, you better slow down both the ground
speed and PTO speed.
I have mowed some of the toughest stuff this year. Broke 1 sickle. My fault. Got lazy and didn't change it when I should have.
Haven't broken a pitman stick in a couple years!!!
 
James Howell has it right. Use a 4" grinder to sharpen the section bar, even worn knives
can be made to cut fairly well. An out of register knife will run real hard no matter how
good the knives and guards are.
 
Thank you all for the replies!

Dad and I managed to get the mower in register today. Was still difficult to slide the adjusting rod, but it eventually moved enough to true it up. As I said earlier, we have already replaced the blade, including brand new sections (did it after the first blade broke).

The lead was also out--we fixed it after fussing through similar "rusty" problems as what we had with the adjusting rod.

Made sure the hold-downs weren't too tight, and took it for a "spin." Mowed the best it ever has, even in the *thick* "swamp grass" I was dealing with. Found myself wishing my 841 Ford had a slower ground speed, though...

Didn't break any sections. Didn't break any blades. Didn't break any pitman arms. Mowed about 1/4 an acre. The most I've been able to mow without tearing something up haha!

Dad has made the two latest pitman arms I've used. The first was out of pine, the one that's on there now is out of hedge-apple. What do you all think about a hedge-apple pitman arm? Think it will last?

Some more pictures for your viewing pleasure...

Two pictures of the new pitman arm (and a photobombing cow):
mvphoto26617.jpg

mvphoto26616.jpg


They didn't know what to think of this new noise maker in their field (the tractor is off in these pictures):
mvphoto26613.jpg

mvphoto26614.jpg

mvphoto26615.jpg
 
Well, I guess now we know why it was out of register!

I guess making your own pitman "wood" to an out-of spec length, from wood you question, then having problems and having to break loose rusted parts and make adjustments makes a LOT more sense than simply buying the OEM part for a little over $30!

DANG!
 
My father has been woodworking for over 40 years. I don't question his ability to reproduce a pitman arm to OEM specs.

When we first got the mower, it had an OEM JD pitman arm on it, and it was in register. First thing we broke was the pitman arm, and we replaced it with one Dad made from pine. The mower was *shocker* still in register once we put the new pitman arm on it. Then we broke the blade. When we put the new blade on, that's when it got out of register.

Then we broke the second pitman arm. Didn't have any pine around, so he tried hedge-apple. Just to see if it would work. Have already mowed more with it without breaking anything than I had to date. So, we'll see.

For the record, all three pitman arms that have been on this mower since I got it have been identical in length. And I've saved myself $60 and counting.
 
Unless you run over a land mine, the hedge apple ([i:654c4848f0]a.k.a. bois d'arc here in NE Texas[/i:654c4848f0]) pitman should last quite a while.

Thanks for the update on your mower.
 
My No8 mower moves out of register with use. The later mowers added a set screw as well as the pinch bolts on the adjustment bar. I see yours has the set screw. What do the cows think of the slip clutch?
 

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