The purpose of this page is to share information about knotter problems on a vintage McCormick International Harvester 46 Square Baler. The serial number plate lists this machine as: International Harvester, Model 46 Baler, Serial # H. The 46 series was built 1957-1963.
Problem/Symptom~ One side of the knotter mechanism will not knot and makes a mess, other side knots but does not cut clean.
Solution~ Replace and adjust knives, adjust knotter tension springs.
We had hay down in the field, our regular baler failed (again), and we brought out Old Faithful, the IH 46. It made bales that were a little wonky, but it always worked. Until now. It would not knot on one side, and I had to finish tying all the bales by hand and was running out of time. In hindsight it was all pretty simple and straightforward, so maybe I can save someone else some time.
Screenshots from the Manual~
Click any pic to enlarge.
Workflow~
First, remove the bolts that are holding the knotters and swing them up. Penetrating oil the night before helps for removal. Some short blocks of wood help for holding it up and working on it as shown below.
Above~ What a mess!
Clearing the mechanism~
Above~ Removing what I believe is called the keeper blade helps in clearing some of the tangles if they are a particularly bad mess. It is easy to remove and reinstall.
Servicing the knives~
Above~ Front and back view of knife. Not knowing if I could get parts, I tried to sharpen them according to the manual with a tiny file.
Below~ Installed shims according to specs and ran the baler again. Same thing, big mess.
Plan B~
The part number for the knife blades is 668 962 R1. With hay still on the ground and the window closing fast, as a long shot I went to our local dealer, Hall Bros. in Norton, NB, just to see. They had these in stock! $7 each, should have done this in the first place.
Above~ The washers/shims on the left control the distance between the knife edge and corner of the “C disc,” the shims to the right keep the distance to the disc which is supposed to be 5/16.” Manual said to bend the part to get the 5/16 spread but I felt safer opting for shims at this point. For the blade, I sprayed penetrating beforehand and the setscrew budged.
Above~ Now with the new knife blades installed, the distance is too great and some shims must be removed and distance reset to 13.49mm to 15.08mm (17/32″-19/32″). Above is a bit over 16mm–the new blade makes the gap too wide.
Above~ With new knife blades and clearance set, it was time to tackle the tension springs.
Adjusting Knotter Tension~
The troubleshooting section of the manual lists all kinds of things that can happen from improper tension adjustment. I noticed that the one on the right (that was working properly) had more threads showing than the one on the left. Since twine was getting wrapped all inside the left discs, I wondered if there wasn’t enough tension. Despite spraying with penetrating oil the night before, the bolt was pretty much seized, but managed to get it unfrozen a bit and gave it about 1/2 turn.
Finally~
Between the new knives and the tension adjustment it tied great, clean knots. We never even lost a single bale and were able to finish the job and get hay in the barn ahead of the storm.
Notes~
It would have been far, far easier to just get new knives, adjust clearance and do a tension adjustment in the first place. You can do that in the field.
This baler was our backup baler when ours failed, and it failed a lot. It was loaned to us by a friend, as people will do in these parts to help somebody out. He had dragged it out of the woods, greased it up and showed me how to use it. My wife called it Old Faithful and even wrote an article about it. It was like the Energizer Bunny, and had never failed to work until this year. This got it going again.
See also~
The Old Baler~ Dorothy’s take on Old Faithful
Above~ My friend Ed showing me how to use his McCormick 46 Baler for the first time.
Below~ One of the many times Old Faithful saved our bacon. 2nd cut, beautiful hay.
rudi.baumgarten@gmail.com
2 Apr 2025Hi. My name is Rudi. I live in a small farming community in South Africa. I loved your article above, because it perfectly mirrored my experience with my IH B47. I spent my teenage years on our old fordson Tractor, pulling the baler around baling grass for my mom, who at the time was milking a heard of jerseys. It always confounded me that a blade so small, could cause so much grief. I reached exactly the same solution of shimming the knife holder, independently, which as you pointed out, works a treat. Difference is: in South Africa, those little blades, cost a kings ransom, with our weak currency. But it’s almost impossible to do without them, or to make facsimile. Yesterday a friend asked me for a hand with his B46. It got me searching to see if I could find those little knives for a better price. Then I found your article. Thanks so much for the walk down memory lane.
Jim Stewart
3 Apr 2025Rudi– Thanks for your kind words, glad you found the article. It is always a challenge, isn’t it, because you are dealing with old equipment, supply issues and usually weather issues all at the same time. One thing for sure–friends are our greatest asset when trying to solve these kinds of problems. These old balers are good equipment if we can keep them working. Cheers!
Rudi.baumgarten@gmail.com
8 Apr 2025Exactly Jim, and with all the implement makers putting computer chips in their gear, so that it’s impossible to repair without hooking it up to a computer, to clear the fault, after you’ve installed the spare part, that B46 is gold. I SUPPORT RIGHT TO REPAIR. Have to say(between you and me) yours could do with a lick of paint, and put a compressor thru the knotter sometime🙂😂
Jim Stewart
19 Apr 2025Rudi–Sorry, just now saw this. Yes, I am hoping the Right to Repair movement will gather steam, but like the more recent model cars, the tractors and such are impossible to work on without expensive computer support. I agree the old B46 needs a coat of paint, but the baler is on loan to us so it isn’t actually ours, I just try to keep it going. Besides, we would all wonder if a new coat of paint might “spook” Old Faithful or make it swell with pride lol. Regardless, would have to clear it with the owner, don’t know how he would feel about it (or the old baler, for that matter). Hope all is well, Cheers!
jim.brownlee@gmail.com
11 Aug 2025Hi Jim, excellent website, on my Dad’s farm in Ontario, back in the 1950s when I was young, we had an IH #45 baler and it would always miss tying on the inside knotter, so I had to ride on the twine box and tie the missed knots as the bale was being pushed out the bale chamber, what a dirty job. I kept watching and comparing the two knotters and decided that the inside needle was not placing the twine in the twine keeper properly. It took almost a complete hay season to convince my Dad to adjust that needle to be the same as the outside one. After Dad adjusted the needle properly that baler worked almost perfectly.
Then in 1962 Dad bought an IH B414D and a #46 baler, what an improvement the 46 was, in good hay with the B414D we could tie enough bales in an hour to use a 9,000 ft ball of twine on each side.
But every so often the 46 would miss a bale on the inside knotter, since it was new and under warranty the IH mechanic was out a few times to look at it and check adjustments and installed the updated twine holder springs that went under the twine knife but same occasional miss occurred. My Dad would not let me touch the knotter as the 46 had one year IH warranty on it. The next haying season the same occasional miss problem, so one wet day Dad let me examine both knottera and on the inside knotter frame I found a rough pit hole in the slot where the bill hook tension arm slides out and in and sometimes it would hang up about 3/4 the way down the slot and not put sufficient tension on the bill hook to completely pull the twine through the knot to complete the bow. I filed and polished that rough pit hole out of the slot in the knotter frame and the baler rarely missed a bale after that and we used to put up 10,000 plus square bales a season. Always cleaned all the junk out of the knotters every time we added a ball of twine to the box, kepted the twine knives sharp and always a spare set in the twine box. Eventually Dad add a #10 bale thrower to it and replaced it with a #37 in the mid 1970s, then IH #47 with the “All Twine” knotter, then when my brother took over the farm he bought an IH #430, then 435 and now has a CIH 428 but only does about 800 square bales a season now, most are round bales now. I have never worked on a knotter since the “All Twine” models.
Jim Stewart
12 Aug 2025What a great story with those balers! I can totally see a young lad riding on that twine box (what a great b/w image that would be) dealing with the heat, dust etc. for his Dad.
When I was just trying to get through a small field, I would have to pause the tractor each time, run around and tie the one side, then jump back on and try to keep going. It can drive you crazy but tick-tock a storm is on the way.
These are great comments about a life many people will never know. Thanks so much for sharing and about the different models.
Cheers, Jim
Joshua
28 Sep 2025Hi Jim, this is a great website. I’ve followed the adjustment process and brought an old IH 46 back to life…here in Kenya
Jim Stewart
1 Oct 2025Joshua–Thank you for your kind remarks. I’m very glad that the info was of some use to you and helped you with the adjustments, and nice to hear from Kenya as well.
Cheers,
Jim Stewart