NH 55 rake gearbox disassembly

[mennometis]

Is it okay to push the output spindle shaft in through the gearbox through the output bevel gear? I am having trouble getting that snap ring off the shaft, but maybe it can stay on there if I work the other way. I'm worried about scoring the shaft though.

I'm working on converting the box to grease and want to pack the bearings which appear to be still in good shape judging by lack of slop. I also want to drill and tap the sleeve for a zerk and will need to get the shavings out of there.

 

[mennometis]

Well, it worked to drive it all the way through without taking the snap ring off. Now that the shaft is out, I'm going to take the ring off for ease of reassembly of the gear. I put the new zerk closer to the output end bearing so that it will be further from the frame once assembled. Drilled with 7/32 bit for 1/4-28 tap. Wrecked the seal trying to remove it. The bearing sounded too gritty to clean out in place, so chose to remove it, but the seal was in the way.

Word of advice: Do not tap too hard on the threaded end of the shaft even if you are careful to avoid the threads. My shaft has two cross holes at 90° and the end got squashed because of the missing material. Not sure if the 1/8 cotter pin will even get in there.

 

[flying belgian]

Well, it worked to drive it all the way through without taking the snap ring off. Now that the shaft is out, I'm going to take the ring off for ease of reassembly of the gear. I put the new zerk closer to the output end bearing so that it will be further from the frame once assembled. Drilled with 7/32 bit for 1/4-28 tap. Wrecked the seal trying to remove it. The bearing sounded too gritty to clean out in place, so chose to remove it, but the seal was in the way.

Word of advice: Do not tap too hard on the threaded end of the shaft even if you are careful to avoid the threads. My shaft has two cross holes at 90° and the end got squashed because of the missing material. Not sure if the 1/8 cotter pin will even get in there.

Why would you need a zerk? Once it's full where would it go?

 

[mennometis]

Why would you need a zerk? Once it's full where would it go?

I get ya. It isn't sealed into the gearbox cavity, so then you have to (try to) fill the whole box with grease and then hope some of that grease goes back into the bearings if the seal ever starts leaking (from overpressurizing the zerk, mind you.) The zerk is just a back up for when I don't have time (or too lazy) to open it up and repack the bearings.
Oil is better for the application, as it will splash everywhere. To compensate for their leaky box, NH recommends grease that would never find its way into the bearings on its own.

 

[Wisconsin Ron]

Corn head grease seems to be the ideal grease for that gearbox nowadays.

 

[mennometis]

Well, I finally got that gearbox back together. Not that big of a job to convert to grease.

Raked about 5 acres yesterday morning. Works great for a 70 year-old implement.

I had to bend the "stripper bars" (NH wording) to stop the awful sound of teeth rubbing on them. I used a jack-all sideways between the frame and the offending bars to get the desired clearance.

 

[maqbill]

Well, I finally got that gearbox back together. Not that big of a job to convert to grease.

Raked about 5 acres yesterday morning. Works great for a 70 year-old implement.

I had to bend the "stripper bars" (NH wording) to stop the awful sound of teeth rubbing on them. I used a jack-all sideways between the frame and the offending bars to get the desired clearance.

Thats called 'the field adjustment ' in the manual