problems with sickle mower

Well I hooked up the 451 new Holland sickle mower this evening to try it out on a decent field. It seemed to not cut as low ad I thought the Ford that I used to have did. Maybe I need to replace a few sections but can someone give me a few pointers on making this thing cut well. Thanks guys
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The mower is not cutting all the grass is what its doing. Its jaggy looking cut. The sickles are the undersergrated blades. I was told to not sharpen them. The man who had it said he ran it around 4.5 mph so thats what I tried it in. Was 4 gear on my 4020. Has a new belt on it. What and how do I need to measure the clearance on the sickles and the rock guards. Looks like I may have to much clearance in there.thanks
 
Guards and sections need to sit paper tight or it will not cut well. When I use my sickle mower I use 1st gear NEVER any faster but that is on a Farmall BA. B front end A rear so not sure how that would equate for speed
 
Bar hold downs either need to be hammered down or the guards need to be bent/hammer up. I have been rebuilding and build sickle bar mowers for decades now. Have built many custom fit machines out of junk parts and have a lot of luck. The key to have one cut well is getting the angle of the bar set right and speed of the machine both ground and sickle to match. I Have a JD #9 sickle mower that is part JD and part Ford and who knows what else. Worked good till I let a friend use it and he lost parts of it and have not gotten back to fixing it
 
if the blade being in proper (register) applies to a belt driven mower, might start there:

Best place to start is the Owners Manual for the brand you have. Getting the cutting blade in register with the guards is one of the more important things. Proper PTO speed with correct ground speed will greatly affect performance. A manual is a required item.
 
(quoted from post at 20:54:55 05/19/15) The mower is not cutting all the grass is what its doing. Its jaggy looking cut. The sickles are the undersergrated blades. I was told to not sharpen them. The man who had it said he ran it around 4.5 mph so thats what I tried it in. Was 4 gear on my 4020. Has a new belt on it. What and how do I need to measure the clearance on the sickles and the rock guards. Looks like I may have to much clearance in there.thanks

Yes, it should cut well at 4.5 mph. No you should not need to sharpen those knife sections. The key to it is in the hold downs, they need to keep the sections right on the guards. A friend had a New Holland Haybine that always cut very well. He had two piece hold downs on it that enabled him to easily adjust each one to maintain slight pressure.
 
I have a manual ordered but its taking longer than expected to get it. How do you check the register? If I turn the belt to move the sickle at the end of the stroke it stops just a tad off from center of guard. Is that what your talking about?
 
When ever I buy a sickle mower I like to get a manual and set and adjust it because you never know what the previous owner did and how well it is set. By this I mean the lead of the bar, the pitch of the guards and of course adjust the hold downs. Also since you just got it I would save yourself the agrivation now and replace all the guards and sickle sections. Then you know what you have. Its easier and less agrivating to do it now then when you are wanting to mow hay.
 
grass is the hardest thing to cut with a sickle mower. Without a closeup picture of the mower bar and sickle it is not possiable to give you advice, the only thing we can do, as others have done is guess. Were you running the mower at the max rpm's ie true pto speed or were you running a gear too fast and had your tractor throttled down so you could run at the mph the former owner said? Did you buy this from a true farmer or farmer want to be? If the mower cut for the other guy you should be able to hook it up and go straight to mowing with no need for any adjustments. Please Post good close up pictures of the bar and sickle.
 
I will post some later today of close ups. Yes he mowed with it but it was 4 years ago. I mowed in 4th gear which is around 4.5 at 540 rpm. I'll try 3rd next time. With all this rain I won't be cutting for awhile. Thank you
 
When you get your manual, you'll have all the info you need. Those are real good mowers. The newer version did not have ledger plates on the rock guards, and you can sharpen the cutting edge of the guard with a weld grinder if it's rounded. Can't do that if it has ledger plates tho. You can sharpen the under-serrated sections with a weld grinder too. Of course, you obviously only sharpen the top side of the section. Years ago, it was common to see people use smooth sections, which you'll eventually end up with if you sharpen them enough times. A section that is bent down will cause you lots of grief - it lifts the neighboring sections and causes them to cut poorly or even choke. I don't think there's any way to change the register on that mower, but I may be mistaken - never needed to do that on mine. Shortening your top link tips the guards downward for a lower cut, but there are obvious limits, again - the manual will tell you. It's hard to tell from your pics, but it looks like it wasn't choking, so I'd guess a slower travel speed or sharpening would help you get a smoother cut. New sections & guards would be good, but only if needed. Someone mentioned changing the belt often - mine has the original belt - it must be 30 years old. That belt is probably pretty expensive, and no need to change it if not necessary.
 
Thanks for the response. I'm ready to read over my manual. I paid $500 for mower with extra sickles. It runs real smooth. Is that a good price. He came down from 800 to 500
 
It should start and end the complete blade cycle with the blade section directly covering the guard ledger plate. Not off partially covering the guard, this can cause choking or binding.

The older mowers with wooden pitman rods. When the pitman had to be replaced, it was easy to get the mower out of register, (some call it time).
 
$500 - I would call that a very good price.

A sickle mower that has high hours of use will show wear on the bottom side of the bar, between the guards. My neighbor had a 451 that had severe wear, and it still ran like a new one. He had replaced all of the sections and guards many times, but never had to go into the "head". Another neighbor (actually the neighbor's son) failed to properly tighten the head bolt, and the two vertical plates that the head bolt goes through were destroyed. Plates were expensive, and tedious to change, but it has been trouble free for a couple of decades - troublesome son is now in his 40's, ha. I've replaced the U-joints on mine a couple of times - my tractor has an offset PTO, and it works the joints a lot when I raise it. I could offset the whole mower to help the u-joints, but I like the way it fits my wheel setting.

I hope you have as good of service from your mower as I've had with mine.
 
Here are some pictures of the cutter bar and the guards and knives. Pics aren't the best but tell me what y'all think. Thanks
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(quoted from post at 17:31:35 05/20/15) Here are some pictures of the cutter bar and the guards and knives. Pics aren't the best but tell me what y'all think. Thanks
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How about pics showing the hold downs? They are what makes the difference. One from above one end or the other would help too. That would show how good the alignment of guards is.
 
(quoted from post at 14:48:53 05/20/15) The thickness of the grass is going to determine how fast you can go.

Agreed, light grass tends to push over and not get cut. Good, heavy stemmy late cut is where sickle mowers will really cut fast. Back in the day most guys tended to cut later. The farmer that I worked for would be mowing the meadow across the road from us in mid June when it would be very thick and five feet high. He had a seven foot side mount Dearborn on his 8N and he would really fly.
 
When you think sickle mower, think scissors. If the two scissor blades are gapped, it won't cut paper. Sickle sections should be down on the ledger plates. Check the registry too because if it's off, you're not getting a full cut across the ledger.

If your ledger plates are warn, i.e. rounded vs a nice 90 degree angle, they need replaces - but you can use a hand held grinder to grind that edge back on - as a temporary measure until you can replace the ledger plates.

I cut with my sickle mower at the highest setting, which is still low, but IMHO, the grass recovers better and you're cutting more grass than thicker stems going down to he root. We mowed hay is week at just a tad over 5mph and it was heavy orchard grass with a bit of dew. Sometimes when I get clogging, it seems to me it's because I'm going to slow. A little faster seems to allow the hay to fall over better, kind of like kicking the feet out from someone from behind. I also think the shear mass of hay being plowed into helps push hay off the cutter bar that might otherwise linger and make for a clog.

Good luck,
Bill
 
(quoted from post at 19:54:40 05/20/15) When you think sickle mower, think scissors. If the two scissor blades are gapped, it won't cut paper. Sickle sections should be down on the ledger plates. Check the registry too because if it's off, you're not getting a full cut across the ledger.

If your ledger plates are warn, i.e. rounded vs a nice 90 degree angle, they need replaces - but you can use a hand held grinder to grind that edge back on - as a temporary measure until you can replace the ledger plates.

I cut with my sickle mower at the highest setting, which is still low, but IMHO, the grass recovers better and you're cutting more grass than thicker stems going down to he root. We mowed hay is week at just a tad over 5mph and it was heavy orchard grass with a bit of dew. Sometimes when I get clogging, it seems to me it's because I'm going to slow. A little faster seems to allow the hay to fall over better, kind of like kicking the feet out from someone from behind. I also think the shear mass of hay being plowed into helps push hay off the cutter bar that might otherwise linger and make for a clog.

Good luck,
Bill

Bill, it is impossible to tell for sure but it sounds like you may be confusing ledger plates, which support the back of the bar, with the guards, which are in front, that the knives run on to shear the crop
 
(quoted from post at 21:37:41 05/20/15) It's not intended to be a finish mower.

Agreed, though it is advantageous to have your mower working properly, lawn grass, being blades only, would just push over without support help from lots of stem as in the field.
 
Under serated sections are designed to be sharpened. Have done that hundreds of times and would use them till there was no sine of the serations. It is the over serated that are not supposed to be sharpened as it is said they are self sharpening. I have neverrun over on a mower and never wood. The Over were designed for wheat straw that is ripe, not for grass of any kind. The under is designed for legumes and heavy stem grass, not a fine steem leaf type of grass, for that the smooth section was used and you sharpened then twice or more every day. But yes the underserated are ment to be sharpened when cutting starts to get bad. Bought my first mower in 1958 being a horse drawn unit from the 20's-early 30's.
 
No - the ledger plate is riveted to the guard. It is the flat surface the sickle sections ride on and cut against. One half of the scissors is the
triangular sickle section and the other half is the guard. On that guard is a riveted flat plate and it is the ledger. On the guards for my MF32,
the ledger plates are just wide enough to overlap the guards by 1/16 to 1/8 inches each side. That overlap edge is what I'm talking about
grinding to 90 degrees so you have a sharp edge for the sickle sections to scissor with.

Not sure I'm being very clear in what I'm trying to say, but if you google New Holland part number, 39656, it is the ledger for their guards - as an
example.

Thanks!
Bill
 
Use a feeler gauge, .015 for a starter. You can buy or make a 5 foot bar to bend the guards.
It also looks like you have excessive spring tension for the end of the bar. Grass is cut lower on the inside than out at the end. Walk out to the end of the mower in the down (cutting) position. Lift the end of the mower. It should "weigh" about 35 pounds. Less than that and it is bouncing in the air a lot. While you are there check and see which setting your outer shoe in on, high, medium or low. Then check the inner shoe too.
 
The later 451 mowers didn't have ledger plates on the guards - only at the ends. From the photos it's hard to tell for sure which guards are on the mower in question.
 
Yes - understood.

I struggled to find a pic of a New Holland guard with a ledger plate on it - LOL. When I bought my MF32, it came with probably 3/4 of the new guards with ledger plates on them, so I changed those and the rest I changed this year after buying a parts MF32. I have not had to replace a riveted ledger plate - yet.....
 
Replace them when the cutting edge gets rounded. It's a two man job, unless you have three arms, ha. Maybe someone will chime in that has an easy way to do it. I did change them on another mower for an elderly friend, and used bolts instead of rivets. He was in pretty bad health, and I don't think he ever used the mower after I changed them, so I don't know how it lasted.
 
the correct guard casting number is 218 and was shipped to me painted New Holland yellow manufactured in india. before my 455 had all 215's painted red and they made the section tips ride up into space instead of staying down on the smooth cast in ledger plate. the 215's ledger plate height above the bar top was too high forcing the section up. the 218 guard allowed parallel section to ledger plate top surface orientation. the clips were replaced with high rise clips to clear the bolt on section nuts and just marked the top of the sections when cycled by hand. going thru the same stuff as you, and hope this helps. be well.
 

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