# New Holland 488 Haybine



## weatherman (Dec 5, 2008)

I purchased a 2008 NH 488 Haybine in summer of 2009. I'm not sure exactly when my problem started. I noticed the lower roller gib key that retains the lower roller sprocket was missing. I replaced the key two times ensuring the sprocket was lined up with the upper sprocket. For some reason the key gets worked loose when the sprocket is in motion. I usually rely on my son who is a professional welder to weld for me but he was unavailable to my regret. So, I had the local farm equipment repair company make the weld and look over the lower roller. He made the weld which failed after an hour of cutting hay.

My questions are, after a bit of history, has anyone experience similar problem or might share a theory or two. What would you recommend best course of action. The farm equipment repair company is coming back out Thursday morning to figure this out.

Thanks in advance.


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## mlappin (Jun 25, 2009)

I've never worked on or ran a 488, but my guess is that the key had been missing long enough and now has either the hub or shaft worn out. When you say gib key, you are talking about the tapered one you drive in with a hammer?


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## DSLinc1017 (Sep 27, 2009)

I would have to agree with mlappin, I would guess the shaft is worn out under the sprocket. The sprocket then has play in it so the key gets hammered on and breaks loose. They might have to shim up the shaft with weld, then grind down for a snug fit. Weld the key on the end.
Also check the sprocket, as it to might have too much play and need to be replaced.


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## mlappin (Jun 25, 2009)

Okay, I looked it up here, http://partstore.agriculture.newholland.com/us/TopekaNH/index.php?target=epc_manuals_detail&sl=EN#epc::mr58098ar3176393bi413187-13 it appears the stub shafts in the conditioning rolls are replaceable. If the shaft is wore too much that would be my first recommendation, if just slightly wore maybe try getting another sprocket with the same number of teeth but uses a browning taper lock hub.

Another possibility if New Holland thinks that silly little stub shaft is made of gold and plated with platinum is to pull the stub shaft out and take it to a competent machine/welding shop and have them build it up, turn it down and cut a new keyway. I could easily do that for you for a 12 pack, but I'm sure you can find somebody a lot closer to home. Then you still might want to consider an aftermarket sprocket that uses a taper lock hub instead of that silly gib key.


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## mike10 (May 29, 2011)

The original equipment rolls do not have replaceable shafts. Replace the hub and use Loctite when reinstalling. Be sure the rolls are not touching each other as this will cause the keys to work out.


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## mlappin (Jun 25, 2009)

mike10 said:


> The original equipment rolls do not have replaceable shafts. Replace the hub and use Loctite when reinstalling. Be sure the rolls are not touching each other as this will cause the keys to work out.


Thats too bad as they list a stub shaft for replacement rolls. I wondered when they might have switched as my discbine, 495 and 499 had welded stubs.


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## weatherman (Dec 5, 2008)

Thanks for the inputs. I just haven't had much time out of the field to really consider which way to go...been up past 20 hours bringing in hay, tomorrow one more field. I will research your suggestions tomorrow night. Let you know what happens Thursday.


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## mike10 (May 29, 2011)

mlappin said:


> Thats too bad as they list a stub shaft for replacement rolls. I wondered when they might have switched as my discbine, 495 and 499 had welded stubs.


The bolt on shafts go back to the late 60's with the 469 haybine. Those machines came from the factory with bolt on shafts because removing the shafts was the only way to install the rolls on those haybines. Other than the difference in the shafts the rolls between the 469, 479 and 488 are the same and instead of offering two different parts for those three units only the 469 style roll is offered through parts.


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