(800) 853-2651
SHOP NOW

NH 565 breaking shear bolts

F

Fordfarmer

Well-known Member
This thing has me stumped, and it's wasting time and shear bolts when I should be baling. The bolts are breaking - not being sheared - usually at the end of the threads. It started doing this a couple years ago, but not this bad. I've replaced the flywheel bushing, since there was a little play. I replaced the shear bolt bushing because it was getting a little out of round. I've replaced the knives. It's NOT being overloaded, the needle safety latch is not causing this... What am I missing?
And I am NOT happy with that stepped, only available from NH shear bolt. $3 each, and a 2 hour round trip to get them. I think there's going to be a drill bit enlarging that hole to 3/8".
 
Is your slip clutch to tight ? Ran a hesston 4910 baler that kept breaking shear bolts the guy that ran it before had the slip clutch tightened down way to tight I backed it off and I went from shearing a bolt every 30 minutes to one or two a night and I think the slip clutch could be backed off even more the clutch should be just slightly warm after running a while
 
This is a small square baler , right? I have seen the brake pad that holds the needel yoke/arm worn and slip , letting the needles drop just enough for the stop block to jump into the chamber, stoping the plunger, and shearing the fly wheel pin. Does the pin shear right after a bump, or series of small bumps ?
 
That may be a possibility. I had to tighten it last year, as it was slipping too much (and getting HOT). Maybe I overdid it. Maybe I've been tracking down and eliminating contributing factors, and then added one!
 
Check the feeder fingers for interferance. I had a situation where the feeder fingers would on rare occasion lock up against the pipe ( I think that is the feeder system on your baler). No consistancy to when it would happen. made a mess of the chains too.

Also that baler needs to run at fairly high RPM. When you slow down the RPM, to protect the baler, it can actually make the problem worse because the baler needs the momentum of the flywheel to smooth out the flow of material. The tractor has the power to force it but that is when the shear bolt goes..Bang!

When it breaks, is the Needle latch in the chamber stopping the crank? or does some other action cause the break?
If the needle latch is not in the chamber you can pretty much rule out knotter related causes.
 
The other thing on the bolt itself is that #2 isn't brittle like #8 and takes more whacks to break, plus the smeared steel where the bolt broke, is easier to find when trying to locate the stub so that you can punch it out.

2. I find that if I use a locking nut and do not run it all the way down, leaving the bolt to move a bit back and forth, they work better.
 
Have you checked to see if the needle latch/plunger stop is properly adjusted. ...? I had one that was slightly out of adjustment and it would vibrate into the chamber just a fraction and occasionally hit the plunger and Break the shear bolt.
 
Thanks for the ideas. I loosened the slip clutch a bit and got the shear bolt hole drilled out to 3/8" instead of whatever metric size it was (that is HARD steel!), but it started raining about then, so no chance to try it.
I'll check the brake and latch adjustment, but it's not the latch hitting the plunger arm that's breaking the bolts. There's no Bang! - the bolts just break and the baler stops.
 
You must log in or register to reply here.

Similar threads

R
NH 469 Haybine problem
Replies
13
Views
679
MJMJ
M
L
Unthreaded Carriage Bolt Blanks?
Replies
14
Views
484
caterpillar guy
C
R
NH 469 Haybine question
Replies
5
Views
715
mikewood869
mikewood869
A
47 B Transmission Diagram
Replies
14
Views
618
50supera
5
R
NH 488 Haybine breaking knife drive bolt
Replies
7
Views
1K
Round3Ranch
R
Tractor Parts Tractor Manuals

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.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top