NH 469 Haybine problem

[ridgeandvalley]

Been a while since I posted here. I've got an old NH469 haybine that I use to mow down less than 10 acres twice a year. It's not pretty,
but when it works, it gets the job done nicely. I've got an ongoing problem however... the bushing and bolt that connect the cutter bar to
the wobble box keep failing. Bolts get SUPER hot and bushing gets destroyed. I've replaced numerous bolts and the bushing has been replaced
3 times in the last 3 years. I can replace the bolt easily enough, but I have to have a guy press in the bushing, and it puts me out of
business until I can get it back. Last year I bought a Ford 501 sickle bar mower as a backup. I've used it to do a couple of cuttings
(almost pure grass hay), including first cutting this year and it gets the job done all right. If I could figure out what's going on with
the haybine, I'd fix it one more time and continue to use it, but I'm not willing to keep sticking $100 into it every year just to have it
fail in the middle of a cutting. Any thoughts of what I should try? Or do I just sell it as a parts machine and use the Ford sickle bar?

 

[NY 986]

The cutter bar and guards most likely have extreme wear creating stress on the bolt among other things. Really fine material will add to the stress. Knives and guards will want sharp square edges and tight tolerances. Buy a new knife section and guard to determine how much wear there is in comparison. Probably will cost a few hundred dollars to overhaul but what can you buy for a few hundred dollars and will it have conditioning rolls. If you do not need conditioning rolls to dry the hay then maybe just move on to the Ford mower.

 

[NY 986]

Before inflation took off a couple years ago a parts 469 would sell for 6-700 dollars. A good 469 would have been 1,500. You would have to spend quite a bit more today to get either and they no longer show up at auction on a weekly basis. Last month I saw a very marginal 489 sell for 3,000 dollars. Normally, such a 489 would be 1,700-1,800 dollars.

 

[ridgeandvalley]

I did replace most of the older sections over the last couple of years, and tried to adjust the guards so that they didn't have gaps between the section and the guard. The guy who came and took the bar out to replace the bushing thought that it moved pretty easily by hand.

 

[300guy]

I don't see it mentioned here, but you do grease that bolt and bushing don't you? There should be a grease zerk on top of the sickle bolt.

 

[Jim in NC]

Years ago I had a 467 with a similar problem. I noticed it had some play in the wobble box which caused the sickle to hesitate changing its direction of movement. For kicks I pulled the cover off the wobble box and noticed the tapered bearing. I tightened it a little much like adjusting the front wheel bearings on my old f150. It certainly helped the 467. It cut better and ran much quieter. What I believe is that the excess play was causing more stress on the bushing and not allowing the sickle to make its full stroke and thus poor cutting.

 

[shaun wallace]

Are you using correct bolt and nut and torqueing in center of stroke.

 

[mennometis]

I've gone through 2 bushings this year already, but I am blaming it on cheating last year and cutting the hay high, so it is doing double duty in fine prairie wool grass this year as I try to clean up last year's mess.

My 479 has a split drive head where you just loosen the clamp bolt, pry it open and the bushing drops out on its own. The new one drops in easy as well, all done in the field. You have to set the final height of the bushing in place with best sickle movement before retightening the clamp bolt.

 

[lastcowboy32]

Check the alignment of your wobble drive to your guards/cutterbar.

The knife may slide easily through the guards once the bolt is removed and it's freed from the wobble drive. But, once the knife is bolted into the wobble drive pitman, is that alignment preserved? Maybe check the drive end of the knife, the first few sections and first few guards to see if something is rubbing, once the knife is bolted to the wobble drive.

Another test is...set the haybine up and latch it, for safety. Get on your tractor and get the haybine up to 540 PTO RPM for a minute or so. Shut off the PTO at 540RPM. Does the haybine "coast" a little, or does it stop dead?

Then...shut off your tractor (very important)... make sure your haybine is locked in the up position (should have been already)... then gingerly use your hands to feel for hot spots at the bushing, bolt, first few guards, first few sections, etc.

If there is a rub...you'll find it.


Again. Please make sure the haybine is in the locked up position and you shut the tractor off before inspecting!!!

 

[Northvale PA]

There is a bearing Below the wobble box that pivots the arm which drives the knife. I replaced that bearing and immediately stopped going thru the bushings so fast. Also, I cut the trash bushings out by threading a hacksaw thru the hole. The steel is not hardened. As soon as I got a cut most way thru I would break it out with a screwdriver. Then I would hammer in a new one. I could replace one in about 20 minutes without a press. Plenty of practice.

 

[superc2010]

Are you using correct bolt and nut and torqueing in center of stroke.

what is the correct bolt and what is the correct way to tighten the bolt
do you use flat washers, or lock nuts, what threads

 

[Bruce from Can.]

I think the same knife my 488 will work in your 469. New knives have a bolt/nut that you tighten around the bushing, instead of having to press the bushing in like the old style. If you cannot remove the knife from your machine by just pulling it out with your hands, you will need to check to see if you have guards tipped up or bent down. Bent guards making resistance to slide the knife will shorten the life of the knife bushing

 

[FarrviewSouth]

I agree that I would double check the height you put the bushing I compared to the knife. If they are no aligned the. It ”pulls” on the bushing when you tighten it down, twisting it and it fails faster. Cost me two bushings when I paid for that tuition

 

[MJMJ]

This is an older thread bumped by a new hit and run member. The original thread starter hasn’t been around since last summer, hopefully he got it figured out.