NH 273 Needle Timing Or ?

SaveMy50

Member
Nephew broke both needles. Apparently flywheel shear bolt broke mid tie (needles up), and the flywheel was reversed a bit, and attempted restart with needles part way up. Not what I would have done, but that's the info I got.

Brazed/welded both needles, not perfect, maxed out on adjust bolts, and still a bit of rub on knotter assembly (may have to grind tip a bit?).

Have manual but I'm no baler expert. Checked timing, appears ok, main driver (12:00) and knotter clutch marks line up, Hand rolled, and needle timing looks ok, including the plunger/needle stop (in fact I flipped stop plate around for fresh side (was wearing from # of hits).

Earlier in week had issue with knotter stop, it slipped down and caused missed stopping the cycle and multiple mini bales (took a bit to troubleshoot after many shear bolts and a few knotter shear bolts broken). Also cleaned (excess grease) and tightened knotter/needle brake to spec. I got 100 bales no issue following (and prior to this latest needle issue).

Am I missing anything? Don't want to break again.
 
One thing you need to do before doing any thing else is make 1000% sure the plunger safety stop is working because that is how needles get broken the stop is not working so then the plunger hits the needles and breaks them
 
Not sure where the needle is rubbing the knotter but the side of the needle is supposed to rub the knotter frame. Should take about a 4 lb pull to bring it away from the frame. Keeps the needle from chattering and not delivering the twine to the discs consistently.
 
How did you remove the plunger/needle stop to reverse it? Top of pin has very little vertical free space, not sure of what holds that pin and collar in place thanks gobble
 
Thanks for comments. Luckily the plunger/needle safety is working. Broke a few more shear bolts today. So, since I adjusted the needle stop, and got those 100 bales, now the needle didn't quite trip (really long bale). So I adjusted back down a bit, got 3 bales, and then the needle stop missed and the needle double ran and tripped the safety. Then looked around closer and found the needle drive arm bolt in the middle loose, tightened right up (it didn't seem to bother the needle cycle friction at all). Seems I cant find the proper needle stop position. Too high and the needles won't trip, too low and the needles don't stop tripping. Is there anything on the main assembly (I.e. chain drive, clutch, knotters, brake, needle drive) that can upset the balance? Am I missing a bearing? I think I mentioned I tightened the brake to spec, but I didn't look at the brake pads.
 
So I can reverse a minor bit, only to help clean the chute out, but can never reset the needle in reverse. We all know (now) not to start baler unless needle are in home position.
 
(quoted from post at 16:02:59 07/11/16) One thing you need to do before doing any thing else is make 1000% sure the plunger safety stop is working because that is how needles get broken the stop is not working so then the plunger hits the needles and breaks them

I agree a correct operating PH safety stop is very important.

PH can't hit needles because PH has slots for needles to pass through when needles are cycled. Hay being pushed by PH or foreign objects are what breaks/bends needles not PH.
 
So have manual and attempting to adjust Knotter stop, but a bit confused by step A (below). Aren’t the needles and knotter assembly in home position (i.e. not moveable) until the arm is tripped? Or does it mean to pull on the needle yoke? The rest of the procedure looks straight forward. As noted earlier, I adjusted the stop higher prior cause it looked like it slipped down, but only visually, although it worked for a while. I will look closer at the metering wheel adjustment as well, as I am aware of the both bushings are worn, more on the trip arm side.
38020.jpg
 
Ok so attempted to set the needle stop according to book, but it wouldn't work. When the stop/clutch pawl gap is set at 1/4", the pawl continually misses the stop and won't reset the knotters. And when I close gap too much the clutch disc end that holds the pawl spring barely clears the stop during a cycle. I don't think my pawl has much wear, but I did file both the pawl and stop a bit to get a better square fit. Pictures below. Won't get a trial for a couple of days, rain. Appreciate any comments that may help. As noted earlier, my move on the stop was up ~ 1/8" (and was at max rearward position) when I got those 100 bales, of course I didn't know what the stop was running prior to issues.

Checked timing, matches on clutch hub & disc within 1/4" as required (~3/16) and needles entering chamber properly. Needle penetration a bit deep, maybe 1/8 too far up, but hasn't been an issue to date, so didn't move.
 
Well my adjustments appear to be working, got 100 bales yesterday. No apparent problems with the knotter stop. Broke bale ~ every 20th? Noticed more twine residual around knotters. It was crap hay, well rained on, will know more today as will be baling some slightly better stuff.

Running with two welded needles at maximum adjustment, as noted prior, seems like extra tension on knotters each cycle. Have a new needle and an unwelded needle with tip repair. May try them see if better adjustment. Know there's supposed to be a minor rub on knotters (side) but the not the tie (lower) underside.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top