older BCS sickle bar mower adjustment and sharpening and related items

[mkeith]

I recently bought a used sickle/cutter bar mower.

I ran it for a while today on my BCS tractor. (I believe it is a 715). The results were only so-so, so I wanted some advice. What I saw was that not all grass was cut. Some was just pushed down. Also, a lot of grass got trapped between the moving blades and the stationary blades. And kind of got pulverized there. In the densest tallest grass areas with the driest, stiffest grass it did pretty well.

Anyway, here are the questions:

First, the blades are serrated. Can I sharpen them with a file anyway? Do you take the blade assembly off to sharpen it? How often do you sharpen?

Second, the guy I bought it from (seems quite knowledgeable) said that there are two adjustments, one to keep the moving blades pushed against the lower blades, and one to keep the bar (behind the moving blades) pushed forward.

He said that the first adjustment (keeping cutting blades pushed against each other) is done by hitting the tension arms with a hammer at a particular angle (loosening is done by hitting them right in the middle). He suggested using a punch to avoid damage. I did try this, and it didn't seem to increase the tension. The blades still seemed a bit loose. Maybe I didn't hit it hard enough? Not the right angle? Maybe the procedure is wrong?

How do you do the second adjustment? I think he told me, but I forgot. It may have been the same basic idea as the first one.

Does anyone have a link to a user's manual for this thing? I think I found a service manual online, but it is almost entirely just diagrams.

Also, what do you use for lubrication? I think I saw somewhere online one guy used chainsaw bar lube. Seems like that would be OK. Note: it has two zerk fittings, but I am talking about lubing the sliding parts, not the oscillating mechanism.

Lastly, I was running at pretty low throttle setting, afraid of wearing out the cutter needlessly. What is the correct throttle setting for a cutter bar?

I know it is a lot of questions. I will be grateful for any and all answers.

--McKenzie

 

[farmerboybill]

Hey McKenzie,

First - how old a mower? Does it have rock guards out past the sickle sections, or are they about the same as the sickle sections? The older ones with the longer rock guards aren't as user friendly and have been off the market for a couple decades.

Sickle mowers really like a taller, heavier material to do an effective job. Finer stuff gets missed. Shorter stuff builds up on the cutterbar.

You can sharpen serrated blades. You only sharpen the smooth side while doing the sharpening.

you can only add so much pressure to the sickle bar. Adding too much pressure will cause it to bind, add friction, and greatly shorten the life of the bar and guards. Most I have seen have a bolt and jam nut assembly. You loosen the jam nut and turn the bolt to increase tension on the bar.

Here's a manual - http://www.bcsamerica.com/uploads/2013/02/OpMan.att_.Cutterbar.pdf

The material being cut releases liquids that help lubricate the cutterbar. If you feel you need more, just have some cheap veggie oil to dump on every now and again - but it really isn't necessary. If you're harvesting the hay, I'd hesitate to put anything on the cutterbar that I wouldn't be willing to eat. Grease zerks should be given a couple pumps daily or every 8 hours (seems there should be more than 2...). If there isn't one there yet, you should install a zerk on the main gearbox, remove the second bolt, and pump into the gearbox until grease comes out the other bolt hole. put the bolt back in and give it 5 more pumps.

You got it right about throttle setting - at and idle or JUST above an idle. Running them faster is stressful on both you and the machine.

 

[mkeith]

Hey McKenzie,

First - how old a mower? Does it have rock guards out past the sickle sections, or are they about the same as the sickle sections? The older ones with the longer rock guards aren't as user friendly and have been off the market for a couple decades.

I think the rock-guards are about even with the sickles. If you follow this link and look at page 15, that is pretty much what it looks like.
http://www.bcsamerica.com/uploads/pdfs/Att_Cutter_Pre95.pdf

Sickle mowers really like a taller, heavier material to do an effective job. Finer stuff gets missed. Shorter stuff builds up on the cutterbar.

You can sharpen serrated blades. You only sharpen the smooth side while doing the sharpening.

you can only add so much pressure to the sickle bar. Adding too much pressure will cause it to bind, add friction, and greatly shorten the life of the bar and guards. Most I have seen have a bolt and jam nut assembly. You loosen the jam nut and turn the bolt to increase tension on the bar.

I could see the blades move up and down. Also, I could easily slide the blades back and forth by hand. My initial thinking was I would tighten it up until it was binding, then loosen it a bit. But I was never able to get it the slightest bit tight.

Here's a manual - http://www.bcsamerica.com/uploads/2013/02/OpMan.att_.Cutterbar.pdf

Definitely not like that.

The material being cut releases liquids that help lubricate the cutterbar. If you feel you need more, just have some cheap veggie oil to dump on every now and again - but it really isn't necessary. If you're harvesting the hay, I'd hesitate to put anything on the cutterbar that I wouldn't be willing to eat. Grease zerks should be given a couple pumps daily or every 8 hours (seems there should be more than 2...). If there isn't one there yet, you should install a zerk on the main gearbox, remove the second bolt, and pump into the gearbox until grease comes out the other bolt hole. put the bolt back in and give it 5 more pumps.

I will see if I can figure out what you are talking about with the zerks. I think the two zerks I have are just on the gear box and another on the u-joint (or yoke?). Point taken about lubes! I am worried vegetable oil might eventually get kind of gummy though. I do usually feed the grass to my goats. I don't really make hay, I just cut a couple of days worth of grass and weeds at a time to avoid buying hay. Maybe if I get the mower working better I'll try to do the hay.

You got it right about throttle setting - at and idle or JUST above an idle. Running them faster is stressful on both you and the machine.

Thanks! So I guess you've never heard of adjusting a unit by striking on the "Holder, Blade" or "Holder Strip" (terminology from the parts diagram)? It is definitely not adjustable by turning any bolts or anything. There is only one bolt and no return spring or anything like that.

 

[farmerboybill]

Pics of the unit would be helpful.

So the manual I linked was the 1995 and newer mower manual. This is the 1994 and older manual - http://www.bcsamerica.com/uploads/2013/02/OpMan.att_.CutterBar.pre95.pdf If you still don't see your mower, you'll need to go into the old shop manuals for the 715, 725, 735. Then, they're only instructions on how to break them down and rebuild them.

As far as greasing, I assumed you have the grease type. Perhaps you have an oil bath mower. Then you'd have a pivot zerk that only needs to be greased every couple days and a pitman zerk that should be greased every 8 hours or daily. Once again, pics would help.

I know of sickle mowers that are tensioned with a hammer, but they're not BCS.

 

[pookins]

Not sure if this will clarify anything any more than Farmerboybill. The previous owner may have been referring to tensioning the the mower blades with a ball peen hammer. For years I used sickle bar mowers in an orchard and sometimes the teeth would vibrate loose (over time). The teeth were held to the blade with metal rivets (pin) and the head of the rivets was hit to reshape the head of the metal rivet into a dome shape using a 3/16-inch punch and a ball-peen hammer. The peened metal rivets held the blades securely. Sometimes these would rattle loose on me, especially if I was trying to re-use an old pin.

Finding the correct size pin was not always an easy task depending on the sickle bar I was working on. I don't know how bcs blades are attached or if they use a standard rivet size. Some older blades used odd metric sizes and that was a problem because "close enough" was never really good enough to keep things in place.

The new "double action" BCS sickle bars have spring tensioner. BCS single-action bars can be special-ordered with spring-loaded tensioners as well.

I hear your frustration regarding cutting grass. Using a sickle bar in tall straw-like grass was never a problem but softer lower (6-8") would clog up the blade or get pushed along into big clumps and prevent the blades from cutting anything. I would try to avoid using the sickebar mower until the grass was taller (with straws) but grass rarely grows evenly on any one block of trees in an orchard, so it was not unusual for me to stop and unclog things. Sometimes going in reverse for a few feet would do this.
For some reason the sickle bar was always my favorite mower on the farm. It was very quite and peaceful to use; was not taxing on the tractor (unlike the larger hydraulic rotary mower); would move at fast pace when conditions were right; I never had to worry about the grass getting ahead of me when I was busy with other tasks (unlike a flail); the sickle bar reached far under the branches of the apple trees, and best of all I could always count on the sickle bar being in working order when many of the other mowers needed parts or repair. It was very dependable.
How tall was the grass that you were trying to mow? Are you looking to maintain a finished lawn or a secondary height? What gear did you end up cutting in (five forward speeds from the spec below). I am curios to know how hard the sickle bar is to turn around when you need to go in the opposite direction? Without the differential is the BCS hard to turn with the sickle bar attached? How wide is the your cutter bar? I found that it is easier to always cut in the same direction with the sickle bar mower. The grass flops over in one direction and going back on that freshly cut grass in the opposite direction encourages clogging.
I called Joel at Earth Tools in Owenton, KY once and asked him about the sickle bar. The guys there are very helpful. Depending on your goals, the 20" BCS Brushcutter mower or Palidino flail mower might be the ticket. I have heard that some of the BCS rotary mowers have issues (not the Brushcutter or Palidino). The really small one-wheel rotary version might have has some sort of gearing issue but not really sure exactly what). I have not heard of issues with the larger rotary finish mowers.
Let us know how things work out and post photo or video link.

BCS 853 walk-behind tractor with 59" double-action cutter bar - YouTube
BCS 853 walk-behind tractor w. 26" Berta Flail mower - YouTube
This is worth watching:
http://www.youtube.com/watch?v=1I4RNenmfFI
These are slow and you need mower hp than the 725:
http://www.youtube.com/watch?v=UfqA_rHld8U
This flail is moving at a good pace but not as wide as a sickle bar:
http://www.youtube.com/watch?v=ToNoR1zl684
SPECIFICATIONS
-BCS model 725 tractor, 2-wheel
-Year ~1995
- Kohler Magnum 8 gas engine
-Speeds: 5 forward, 2 reverse (Hi/Low range)
-Approximate speeds:
Forward MPH: .6 1.24 1.5 3.0 7.4
Reverse MPH: .77 1.85

 

[pookins]

"The 725 has a two stick shifter that gives it 5 speeds forward and 2 speeds reverse in tiller mode. As with most walk-behind tractors, when you reverse the handlebars, the reverse gears become the forward gears in mower mode. This means you will have 2 speeds forward and 5 speeds reverse. The shifter is set up in such a way so that you can access only the first gear hi/lo when in mower mode. The other gears are useless because they are all reverse in mower mode."

 

[pookins]

Page 24 of the instructions posted above does mention using a hammer:
"3)Blade holder adjustment for all point teeth cutter bars - to adjust the blade pressure, use a suitable spacer and a hammer"
The next illustration shows a hammer blow however the written instructions are cut off and only the non-english language portion is displayed.

 

[mkeith]

Sorry for the long absence. I was on vacation and then when I came back I was dealing with other stuff. I did finally take some pictures.

It is a 715 tractor (originally acme but re-powered with the Kohler command pro from Joel at earth works -- thanks to this forum for turning me on to that!), not a 725. I only have one mowing speed (slow). I also have a 20" brush mower. It is good, but with bumpy uneven ground (most of my property) and small wheels, it tends to get hung up (tractor supported by engine guard and mower with wheels in the air). The sickle bar much less so. Some areas I would like to keep reasonably presentable (not like a lawn, but at least like a field you would walk through with normal shoes). Also I want to reduce tick habitat. But I would also like to try to cut grass and weeds to fee to my goats (so I don't have to buy them so much hay). So I think I will need to have both kinds of mower.

The dealer who sold me the mower was not talking about the rivets that hold in the teeth. He was definitely talking about adjusting the force with which the sliding teeth are pushed against the stationary teeth. Also there is a bar that pushes the sliding teeth forward which adjusts much the same way. It definitely SEEMS to be a BCS mower. Many of the parts say BCS right on them (cast parts with BCS cast into the part).

Since my first post, the grass grew quite a bit, and I found that it is much easier to cut when it is tall. It is junky weedy grass all gone to seed. I raked it into a big pile anyway and plan to feed it to the goats. I still have acres to mow. It is a slow process and I don't have enough time in any one day to do it all. I may invest in a more serious tractor (853) and a wider brush mower of some sort. I got this tractor "for free" when I bought a chipper. The Acme motor had thrown a rod through the engine case so he said "if you want it take it. If not, leave it. Same price for the chipper either way." There is also an old mainline tiller "for free." Pretty good deal.

Anyway, I went back to the guy who sold me the mower to buy a throttle cable (he is actually an experienced BCS dealer) and told him about my uncertainty. He found another old mower in his bone pile that had similar adjustment scheme and explained it in more detail. I will try the revised procedure, and if it works (and if I remember) I will let you know. I am much more confident now that his instructions are correct. I was striking at around a 45 degree angle. But apparently you really need to strike the holders so that the hammer is moving parallel to the teeth. A "head on collision" if you will.

Thanks to pookins for the video links and sharing experiences remembrances with the sickle bar! When the grass got taller, it was somewhat peaceful (with ear protection) watching the taller drier grass fall away in waves. And thanks for catching the picture of the hammer! That does look more like my unit. Somehow I missed it on the first pass.

What else. I think my mower is 40 inches wide. The ground is loose, so turning the mower is not too bad. It is helpful to have an already mowed area at each end of the run where you can make your U-turn. I was alternating directions. For me it would be hard to mow the same direction, as I am mowing in a side-hill orientation, and it is much easier to always turn down hill.



See pictures of mower.

 

[farmerboybill]

Hey Keith,

I too went and looked at a mower I have from 1982 and you are right about the "hammer" method of tensioning. Yours surely is a BCS mower. The one in my boneyard has long rockguards that stick out twice as far as the sickle sections. I've been told it was not a very fun mower to use. Looks like you have a mulching or combination mower.

A slightly cheaper way to get slightly more ground speed is to buy some taller tires. The stock tire on a 715 is 16 inches tall. You can go to a 5-12 tire that is 22 inches tall. It should increase your ground speed from achingly slow to moderate. Another option is a Grillo. The Grillo 107d has a higher 3rd gear (3.3 mph at full throttle) than a BCS 853 (2.6 mph at full throttle). It's also $1000 cheaper. Your sickle mower, tiller, and chipper will bolt directly onto the 107d with no adapter. The rough-cut mower will bolt up, but it'll be running backward.

 

[mkeith]

Hey Keith,

I too went and looked at a mower I have from 1982 and you are right about the "hammer" method of tensioning. Yours surely is a BCS mower. The one in my boneyard has long rockguards that stick out twice as far as the sickle sections. I've been told it was not a very fun mower to use. Looks like you have a mulching or combination mower.

A slightly cheaper way to get slightly more ground speed is to buy some taller tires. The stock tire on a 715 is 16 inches tall. You can go to a 5-12 tire that is 22 inches tall. It should increase your ground speed from achingly slow to moderate. Another option is a Grillo. The Grillo 107d has a higher 3rd gear (3.3 mph at full throttle) than a BCS 853 (2.6 mph at full throttle). It's also $1000 cheaper. Your sickle mower, tiller, and chipper will bolt directly onto the 107d with no adapter. The rough-cut mower will bolt up, but it'll be running backward.

Thanks! Maybe the tires are worth investigating. Should also help with the hanging up problem. Mine are old and cracked from exposure even though there is plenty of tread on them. I suspect the unit sat for a long time after the original motor quit. Will the 5-12 tires fit on the stock wheels, or am I looking for a wheel/tire package?

Oh, and if the rough-cut mower is running backward, won't the chipper and tiller also be running backward? I can understand why the cutter bar will work either way, but I think the wood chipper will only cut if the flywheel is spinning the right way. And with the tiller, I guess it could work either way if you turn the tines around, but I wouldn't want it to jump up and run backwards and till me into the topsoil while I am operating it.

--McKenzie