1992 492 Haybine to Roller Knocking

[3020]

Hello ,

Looking for some help with my 1992 492 New Holland Haybine. The top roller has a knocking noise in it and I m trying to determine what is causing it. When the PTO is engaged and tractor is running at slow idle the top roller knocks if you kill the tractor and with your hand move the top roller quickly forward it knocks also when I turn the roller by using the top drive shaft it will knock. The knocking seems to be louder or more located at the end of the roller where the tension crank is but not sure if the noise is just traveling to that end. The Rollers are not in bad shape still have all the rubber on them. Any help or feed back would be much appreciated.

Thanks,
3020

 

[Matt in Oz]

Hi 3020

Got a 492. Will give you some ideas from my experience. Check the clearance between the conditioning rolls. There are thin shims that go between them. Don't let them touch as it will wear out your rolls quickly. Next check any play in the drive universals where they slide on the hex shaft, had
one flopping on mine so had to drill and bolt it fixed on the shaft that was on the bottom shaft. Things like this can allow the rolls to get out of time and allow contact between them. Apart from that check all the unis and telescoping shafts for play. Good luck and let me know what you find always
keen to learn.

 

[caterpillar guy]

Have you tried it in some hay or grass to see if it still knocks. I would suspect some slop in a drive line to the rolls and if you fill them with a material like mowing hay it would stop or at least quiet down. Might help with your problem. I've ran mower conditioners that would make noise then when working in the field they would be quiet from the tension from the flow through the rolls.

 

[rustred]

have you checked the roller brgs. ? if you have a brg. gone the roller will jump and knock.

 

[3020]

have you checked the roller brgs. ? if you have a brg. gone the roller will jump knock

 

[3020]

Hi 3020

Got a 492. Will give you some ideas from my experience. Check the clearance between the conditioning rolls. There are thin shims that go between them. Don't let them touch as it will wear out your rolls quickly. Next check any play in the drive universals where they slide on the hex shaft, had
one flopping on mine so had to drill and bolt it fixed on the shaft that was on the bottom shaft. Things like this can allow the rolls to get out of time and allow contact between them. Apart from that check all the unis and telescoping shafts for play. Good luck and let me know what you find always
keen to learn

 

[3020]

Thanks everyone for the feedback much appreciated I replaced the universal drive shaft on the bottom roller with the telescope hex shaft and that did take all of the slack out of the rollers stop them from hitting each other when you moved the rollers by hand but the cutter still has a knocking in the top roller and at the very end of the roller next to tension crank handle I’m not sure if it is a bearing out on the top roller or not how would you check for that with out tearing into the bearing housing , in one area of the rollers they are touching in spot about 18 inches in length but that is the only spot on the whole rollers where it is touching. I’m going to attempt to attach a video of the cutter running making the knocking noise any feedback would be much appreciated thank you 3020

 

[3020]

I forgot to attach the picture of the spot where the rollers are touching

 

[jhwis]

I forgot to attach the picture of the spot where the rollers are touching

Never had a 492, but can you adjust the gap on the rollers? On a jd 1219 you could. Is the roller rubber itself separating from the roller shaft in the spot it is touching?

 

[3020]

Never had a 492, but can you adjust the gap on the rollers? On a jd 1219 you could. Is the roller rubber itself separating from the roller shaft in the spot it is touching?

Thank you for your reply I thought about adding some more shims under that end of the roller to see if that would help any. There’s no big pieces of rubber coming off where the spot is it doesn’t give the appearance of separating from the roller

 

[jhwis]

Thank you for your reply I thought about adding some more shims under that end of the roller to see if that would help any. There’s no big pieces of rubber coming off where the spot is it doesn’t give the appearance of separating from the roller

Last resort, maybe you could shave off a little of the rubber lug that is touching with a grinder...if you feel that is the issue.

 

[3020]

I hadn’t thought of that but that’s something to consider the rollers will roll freely until they roll around to the spot where they touch at that point you have to put some force to get the rollers past that point then they will roll freely again until the next cycle.

 

[jhwis]

Report back when you figure it out. Good luck.

 

[shaun wallace]

Has a chain been replaced or needs replacing? Are chains tite? There is a slotted sprocket to allow the centering of rolls, it may need shifted some. Stretched chains can cause this too.

 

[Cash4Toys]

The rollers were made round and true. Either a shaft is bent or the rubber is coming loose and has something under the loose rubber causing a height difference. Open the roller spacing equal distance on both ends by adding a temporary shim so the rollers don't touch and run it. If the noise goes away you know the contact is causing the knocking. Then figure out the cause of contact, bent roller or bad rubber. Use something to measure the space where the rollers make contact and again at there widest gap to figure it out. Removing rubber from the roller to gain clearence is less than a band aid repair.

 

[3020]

Cash4Toys - thank you for your reply I will give that a try and see what I find out will let you know. Many Thanks !!!

 

[3020]

Cash4Toys - thank you for your reply I will give that a try and see what I find out will let you know. Many Thanks !!!

Hello Cash4Toys - another question please to get the tension pressure off the shims to be able to put a temporary shim in place on both ends I need to open the rollers all the way up and put something in between the rollers / run something part of way through the rollers to get them to open correct ? Then crank down the tension to get the plate to raise to insert the temporary shim. What would you suggest that be I was thinking a thin piece of wood maybe or maybe a baler plunger charge of hay. Thank you 3020.

 

[Cash4Toys]

If you back off the tension via the tension adjustment crank, you should be able to bar the rolls apart. Or I suppose you could try rolling a piece of tapered wood in the rolls, one each end. On most NH you should be able to bar them open at the shaft end / where the shims are, then just add a piece of 1/4" or 3/8" flat bar to the shim pack already there. Maybe you will need something thicker. On a 479, 489, 499 you can bar right by the shims, but I don't have a manual for a 492, so I can't say, but if you should have a manual it will tell you how to get the shims out. Watch your fingers when working with those shim packs! Do one end at a time.

 

[3020]

If you back off the tension via the tension adjustment crank, you should be able to bar the rolls apart. Or I suppose you could try rolling a piece of tapered wood in the rolls, one each end. On most NH you should be able to bar them open at the shaft end / where the shims are, then just add a piece of 1/4" or 3/8" flat bar to the shim pack already there. Maybe you will need something thicker. On a 479, 489, 499 you can bar right by the shims, but I don't have a manual for a 492, so I can't say, but if you should have a manual it will tell you how to get the shims out. Watch your fingers when working with those shim packs! Do one end at a time.

Ok thanks I will give it try and let you know thanks again !!!!

 

[Cash4Toys]

Actually, if you bar the stops open, you could just use a couple of bolts of the right dimension to run it temporarily to see if the knocking quits.