NH 451 Pitmanless Mower Broken Tilt Lock Bolt

[Oliver550Dave]

Posting here and in Implement Alley -
Bolt broke that locks the push bar in proper tilt on my NH451 pittman-less hay mower. When I picked up the lock (part
#63752) from the local CNH dealer, I asked for and got the bolt, lock washer, and nut that I supposed would fit, but there
is no way that I have found to turn that bolt and get it into the hole on the inside of the push bar assembly. Measuring
it, the bolt is G5, 5/8 x 2.5 cap screw. Thinking I had too long a bolt, I picked up a 2.25 bolt but that is also too long
- or I haven't figured out how to position the bolt to get it to go in the hole!
Looking at Messick's/New Holland parts diagram, I now see that there is are entries for Hex Bolts, 5/8-18 x 1.75, G5, but
is doesn't seem like these would be carriage bolts (machine bolt, round head, short square neck) which the application
calls for.

What do I really need to get this mower back together? A shorter carriage bolt, or use a hex-head 5/8 bolt with lock
washer and nut?

Any other advice appreciated!! I use this mower behind a Ford 3930 tractor.

 

[Steve in VA]

Please forgive me if this isn't appropriate but why not take a hacksaw and shorten the bolt? G5 is fairly soft.

 

[DoubleO7]

Do any of the parts have a square hole to accommodate the carriage bolt?
If no, the carriage bolt square part won't go into the hole for 5/8 unless the hole under thehead is oversized.

 

[Oliver550Dave]

If I knew for sure that I needed to shorten the bolt, that's what I would do. But if cutting off the bolt made is too short in the end, that wouldn't help me. I'm trying to learn from other folks experience where they may have learned what is not obvious to me. To answer another poster's question, the hole through which the bolt is supposed to go is square. Otherwise I might think about using a hex headed bolt and insert it from the outside position, put the lock washer and nut on the inside of the assembly and tighten it the best I can, but have a fear that might work loose too easily. Thanks for considering my predicament!

 

[Blue Jay]

(quoted from post at 16:56:05 05/28/22) If I knew for sure that I needed to shorten the bolt, that's what I would do. But if cutting off the bolt made is too short in the end, that wouldn't help me. I'm trying to learn from other folks experience where they may have learned what is not obvious to me. To answer another poster's question, the hole through which the bolt is supposed to go is square. Otherwise I might think about using a hex headed bolt and insert it from the outside position, put the lock washer and nut on the inside of the assembly and tighten it the best I can, but have a fear that might work loose too easily. Thanks for considering my predicament!

Use a lock nut, it won't come loose.

 

[PJH]

Would a picture help you? My NH 451 is sitting in the yard after using it today. I've had every other part off of my mower, except the piece that you're working with. The owner's manual has lots of service information in it, and I can check mine in the morning to see if it lends any advice. My manual is out in the shop.

I replaced every bearing in my mower last fall, and the owner's manual had step by step directions for the process.

 

[Oliver550Dave]

Thanks for the reply. I've got both parts and operator's manual. A reply on Implement Alley had great pictures that well illustrated that I need to get a shorter bolt (1.5 5/8 carriage bolt) which should work for me. I reworked the wobble box a few years ago - yes, good step-by-step, helpful information in the operator's manual! Thanks, again.