Hesston 1071 cam follower arm rubs on the cam track. Why?

[Bodark]

I have a Hesston 1071 mower/conditioner that has a cam follower arm on the tine bar that rubs against the cam track. I have had all four tine bars out, replaced the plastic bushings, replaced the cam follower bearings, and straightened some minor bends in the bars themselves while they were stripped down. All four were bent at the cam end (I guess from long term stress), but they straightened out pretty nicely. The reel looks good, nothing obviously bent at all. A couple of the bats are a bit bent, but nothing catastrophic looking. I cannot understand why one bar in particular wants to drag on the cam track. I had hoped straightening the tine bars and new bushings would solve it, but no such luck. Any ideas about what I'm missing?

 

[Paul swpa]

I have a Hesston 1071 mower/conditioner that has a cam follower arm on the tine bar that rubs against the cam track. I have had all four tine bars out, replaced the plastic bushings, replaced the cam follower bearings, and straightened some minor bends in the bars themselves while they were stripped down. All four were bent at the cam end (I guess from long term stress), but they straightened out pretty nicely. The reel looks good, nothing obviously bent at all. A couple of the bats are a bit bent, but nothing catastrophic looking. I cannot understand why one bar in particular wants to drag on the cam track. I had hoped straightening the tine bars and new bushings would solve it, but no such luck. Any ideas about what I'm missing?

Could be the bar got bolted up on the wrong side of the supports? About all I can think of. Have a 1091 I'll try to look at tomorrow and refresh my memory, been a long time since I had to work on the reel. I used to have to replace a lot of the cam followers until I started greasing the track like it says in the book. Knock on wood, I haven't had to change one since. Paul

 

[will-max dairy]

I have a Hesston 1071 mower/conditioner that has a cam follower arm on the tine bar that rubs against the cam track. I have had all four tine bars out, replaced the plastic bushings, replaced the cam follower bearings, and straightened some minor bends in the bars themselves while they were stripped down. All four were bent at the cam end (I guess from long term stress), but they straightened out pretty nicely. The reel looks good, nothing obviously bent at all. A couple of the bats are a bit bent, but nothing catastrophic looking. I cannot understand why one bar in particular wants to drag on the cam track. I had hoped straightening the tine bars and new bushings would solve it, but no such luck. Any ideas about what I'm missing?

I wonder if you should check the centering of the entire reel within the frame.


The reel in those haybines is held centered by lock collars at each end.

If the lock collar at the drive end of the reel (where the large sprocket is) is too close to the end of the shaft; then the entire reel can shift towards the cams... which would make your cam followers rub hard against the wall of the track.

The opposite is true of the lock collar on the cam end of the reel. If that lock collar is loose or missing; then the reel can shift towards its drive end. the problem there is that the cam followers will pop out of the cams and then either bend or break the ends of the arms when it shifts back.

I run two 1070 haybines. The first one had a missing lock collar on the cam end (and, being new to these machines, I didn't know it was missing)... I wrestled with the second problem described above for about a season, until I looked closely at a parts diagram and noticed that the lock collar wasn't even there!

Also... check the assembly of the arms in the reel. There is a very specific order of teeth, plastic bearings, holding collars, etc at three points across the bar. Additionally, the center one should have a large bushing/washer that is held in place with a cotter pin that essentially centers each bar in the reel.

I have disassembled reel bars many times to replace teeth and such. I always leave one on the haybine to remain as an example of how the assembly should be done... and... more than once, I've had to disassemble a reel bar after I brought it out from the shop and compared the assembly order to the one remaining on the reel.

 

[will-max dairy]

Could be the bar got bolted up on the wrong side of the supports? About all I can think of. Have a 1091 I'll try to look at tomorrow and refresh my memory, been a long time since I had to work on the reel. I used to have to replace a lot of the cam followers until I started greasing the track like it says in the book. Knock on wood, I haven't had to change one since. Paul

And... as Paul swpa's comment says...

If I remember correctly... the collars at the three locations on each reel bar should bolt to the drive side (towards the big sprocket) of the supports. At the center support, the big washer and cotter pin on the bar goes on the other side of the support (towards the cam).

That "sandwich" of collars and washer/cotter pin holds the bars in the correct position relative to the reel itself.

The stop collars on the reel drive shaft/tube maintain the correct position of the entire reel assembly, including the bars, to the frame of the haybine and the cam.

 

[will-max dairy]

I have a Hesston 1071 mower/conditioner that has a cam follower arm on the tine bar that rubs against the cam track. I have had all four tine bars out, replaced the plastic bushings, replaced the cam follower bearings, and straightened some minor bends in the bars themselves while they were stripped down. All four were bent at the cam end (I guess from long term stress), but they straightened out pretty nicely. The reel looks good, nothing obviously bent at all. A couple of the bats are a bit bent, but nothing catastrophic looking. I cannot understand why one bar in particular wants to drag on the cam track. I had hoped straightening the tine bars and new bushings would solve it, but no such luck. Any ideas about what I'm missing?

The bending of the bars could be from this...

Hesston sold a "speed-up" sprocket to drive the reels (look at the little sprocket on the reel-drive end of the lower conditioning roll)... if the speed-up version is used, the reel on your haybine will be going the equivalent of about 6mph ground speed. That's great, if you are doing easy mowing of tall hay with the push bar on the front tipping the hay forward... the sections cutting the bottom of the stems... and you are and hauling along at about 5mph with the reel gently sweeping cut hay up the apron... cut end first...

If you are in low, tangled growth, and you are slowing down to get a good cut... then the push bar on the front of the machine is not pushing the hay over for cutting before the reel encounters it... the reel is just beating on that mat of hay many times before it's cut and ready to go up the apron to the conditioning rolls. And... the hay goes up the apron top first... which is harder for the conditioning rolls to grab... Between this constant drumming on the uncut hay and the apron plugs that inevitably form... your reel bars and tines will take a beating under these conditions. The bars can bend. You'll break more teeth than normal. It's just bad all the way around.

Hesston sold an apron to hang from the push bar under such conditions to try to keep the forage pushed forward and out of the reel's reach until it was cut.

Or you could switch to the normal sprocket for tough mowing conditions.

 

[Bodark]

I wonder if you should check the centering of the entire reel within the frame.


The reel in those haybines is held centered by lock collars at each end.

If the lock collar at the drive end of the reel (where the large sprocket is) is too close to the end of the shaft; then the entire reel can shift towards the cams... which would make your cam followers rub hard against the wall of the track.

The opposite is true of the lock collar on the cam end of the reel. If that lock collar is loose or missing; then the reel can shift towards its drive end. the problem there is that the cam followers will pop out of the cams and then either bend or break the ends of the arms when it shifts back.

I run two 1070 haybines. The first one had a missing lock collar on the cam end (and, being new to these machines, I didn't know it was missing)... I wrestled with the second problem described above for about a season, until I looked closely at a parts diagram and noticed that the lock collar wasn't even there!

Also... check the assembly of the arms in the reel. There is a very specific order of teeth, plastic bearings, holding collars, etc at three points across the bar. Additionally, the center one should have a large bushing/washer that is held in place with a cotter pin that essentially centers each bar in the reel.

I have disassembled reel bars many times to replace teeth and such. I always leave one on the haybine to remain as an example of how the assembly should be done... and... more than once, I've had to disassemble a reel bar after I brought it out from the shop and compared the assembly order to the one remaining on the reel.

I think you are right about the reel being shifted. The tine shafts are 100% assembled correctly. There is a circular outward dent on the shield over the reel drive from the clutch bolts hitting it, so at some point the reel had slid over. That end of the shaft is kind of boogered up and there was a hose clamp holding in the gib key. I don't know if that gear is ever going to come off. I hate when people do half-ashed repair work.

 

[Bodark]

Could be the bar got bolted up on the wrong side of the supports? About all I can think of. Have a 1091 I'll try to look at tomorrow and refresh my memory, been a long time since I had to work on the reel. I used to have to replace a lot of the cam followers until I started greasing the track like it says in the book. Knock on wood, I haven't had to change one since. Paul

I am certain the tine bars are correctly assembled.

 

[will-max dairy]

I think you are right about the reel being shifted. The tine shafts are 100% assembled correctly. There is a circular outward dent on the shield over the reel drive from the clutch bolts hitting it, so at some point the reel had slid over. That end of the shaft is kind of boogered up and there was a hose clamp holding in the gib key. I don't know if that gear is ever going to come off. I hate when people do half-ashed repair work.

(I edited out a piece of this response... because, you can only tap or pound "so" hard on the shaft in the center of a Hesston 1070 or 1071 haybine reel... because what you see at either end is a stub shaft about 18" long that has a thin (about 1/8" thick) expanding cap that is spot welded to the 4" diameter reel tube... to much stress pounding on these stub shafts and you can easily crack the stub shaft out of its expanding cap)

If you want to remove the Gib key and hub...see if you can tap the hub of the gear further ON the shaft... to get the Gib key out... if you can do that... then you can try to spin the shaft relative to the hub with a pipewrench or (use your imagination)... at which point... if you shine up the end of the shaft... you have a pretty good chance of getting the hub off.

The first time I took one of those hubs off, I didn't know about Gib keys... I ground off the end of the Gib key and tried to pull the hub over the rest of it... not knowing that they are tapered... that was a few hours of my life that I would love to have back, for fishing or some other endeavor...

 

[will-max dairy]

I think you are right about the reel being shifted. The tine shafts are 100% assembled correctly. There is a circular outward dent on the shield over the reel drive from the clutch bolts hitting it, so at some point the reel had slid over. That end of the shaft is kind of boogered up and there was a hose clamp holding in the gib key. I don't know if that gear is ever going to come off. I hate when people do half-ashed repair work.

If you get the hub off in one piece... have a beer to celebrate...

Replace the bearing and stop collar at that end... ensuring that the reel is centered well in the frame...

If there is room, put a spare stop collar behind the hub... so that it will hold the correct position to align it with the other sprockets... then... tap a new Gib key in... that extra collar will hold the hub in place so that the Gib key taper can do its thing.

For the Conditioning roll drive sprockets... they can be bought for 60 bucks... I don't worry about Gib keys... I cut the old sprockets off, Gib keys and all... put on the new sprocket with a piece of regular keystock... and tac weld in place.

 

[will-max dairy]

As far as that bump in the reel drive shield... been there... done that... on my first 1070... the clutch bolts cut a ring in the shield while i was mowing... that clued me in that the reel was shifting over and put me on the path that lead me to finding out that the stop collar was missing...

 

[will-max dairy]

I have a Hesston 1071 mower/conditioner that has a cam follower arm on the tine bar that rubs against the cam track. I have had all four tine bars out, replaced the plastic bushings, replaced the cam follower bearings, and straightened some minor bends in the bars themselves while they were stripped down. All four were bent at the cam end (I guess from long term stress), but they straightened out pretty nicely. The reel looks good, nothing obviously bent at all. A couple of the bats are a bit bent, but nothing catastrophic looking. I cannot understand why one bar in particular wants to drag on the cam track. I had hoped straightening the tine bars and new bushings would solve it, but no such luck. Any ideas about what I'm missing?

But... with all of these quirks aside... I consider the reel drive mechanism about the only downside to a 1070-style haybine.

The conditioning rolls are hardy, the way that they are made prevents delamination like you can find with NH and JD rubber conditioning rolls

The swaybar mechanism and other drive mechanisms are just straightforward assemblies of bearings and such that you can rebuild, as opposed to the enigmatic "wobble drive" used on New Holland et al.

They are, however, getting rare, especially the 7' variants.

 

[Bodark]

Yeah I really like the design of the Hesston from a serviceability standpoint and the overall simplicity. I wish I had found a better example to start with. I came to find out the 2 belt sheave on the main drive shaft has a badly worn keyway and it won't stay tight, even with a new gib key. I had to order a new one ($350!!!!). The shaft it runs on has slight damage and I am going to assemble it with Loctite 660 retaining compound that should take care of the minor wear in the shaft keyway.