NAA leveling box extra hole

[Dan]

My rear 3 point lift leveling box on Rustbucket skips teeth as I try to adjust, so I figured a rebuild is finally in order. Upon tearing it down and cleaning out the old grease getting it ready to install new parts I discovered a second hole that was hidden under the grease. It is not the grease zerk hole and is not threaded. I cannot see a reason for this and looks factory not farmerized. I searched and found a post asking the same question about this second hole but no responses.

Any idea what this is for? Should it be covered with a plug?

TIA,
Dan

 

[Ultradog MN]

My rear 3 point lift leveling box on Rustbucket skips teeth as I try to adjust, so I figured a rebuild is finally in order. Upon tearing it down and cleaning out the old grease getting it ready to install new parts I discovered a second hole that was hidden under the grease. It is not the grease zerk hole and is not threaded. I cannot see a reason for this and looks factory not farmerized. I searched and found a post asking the same question about this second hole but no responses.

Any idea what this is for? Should it be covered with a plug?

TIA,
Dan

Photo?

 

[wore out]

My rear 3 point lift leveling box on Rustbucket skips teeth as I try to adjust, so I figured a rebuild is finally in order. Upon tearing it down and cleaning out the old grease getting it ready to install new parts I discovered a second hole that was hidden under the grease. It is not the grease zerk hole and is not threaded. I cannot see a reason for this and looks factory not farmerized. I searched and found a post asking the same question about this second hole but no responses.

Any idea what this is for? Should it be covered with a plug?

TIA,
Dan

I'd say it's a way out for dirty or excess grease as you pump new grease in, so it doesn't pop out the "expansion plug" in the top of the gear area.

 

[Dan]

Ultradog, I will take a pic when I get down to the shop today.

Wore out, I would be inclined to agree with you but there is more space under the thrust bearing where grease squeezes out. That is where I always see it come out.

 

[Dan]

Here are the pics. Hole is on opposite side of where the grease zerk is. Drilled at an angle where the handle gear rides. The grease zerk is in a raise area with thicker material for the thread length.

 

[Ultradog MN]

I'm gonna say that was farmerized. Who knows why...

 

[Dan]

I'm gonna say that was farmerized. Who knows why...

I have read other posts where this hole shows up. Anyone with a NAA handy willing to check theirs? The part number stamped on the housing looks like 9N565, so maybe this box was from an earlier tractor(?)

 

[Dan]

Well, since the housing had a 9N part number, I checked all my tractors. My 1939 9N has a different looking housing, but the same 2nd hole. My 1948 8N has the same housing and same 2nd hole. Heck, even my 1963 2000 tractor has this same 2nd hole. I guess it is an overflow hole even though my excess grease always flows out the bottom where the shaft exits.

 

[zuhnc]

If it is on the lower part of the housing, could be a moisture weep hole. These things are not exactly watertight! zuhnc

 

[Dan]

Final update. The replacement gear came in. Here is a pic of the current Made in Turkey part with the original. Slightly different design but meshed and worked fine with the original shaft gear.

I filled the box up with fresh grease and swelled the compression cap back in place. When I went to top off the sealed box with grease, sure enough some squeezed out of the 2nd hole so I guess that is what it is for. I guess after several years of use these holes get plugged up with dried grease and dirt so it leaks out of the bottom where the shaft goes through(?)

Anyway, paint touched up and ready to get back to work.

 

[HCooke]

Dan, I think you have figured it out. I don't have as many tractors as I used to have but on the few that I have left (1 8n and 1 2n) they both have that hole and grease comes out when you put new in.

 

[Ultradog MN]

Guess I've been away from the 4 banger Fords for too long. The 3 bangers don't have that hole.

 

[Tim PloughNman Daley]

It is likely an over flow port sp excess grease can escape. Maybe. Could be a manufacturing procedure for access to drill the Zerk? I'd have to inspect at close range. Carbs have manufacturing drill holes that allow you to reach in on opposite side to get to usable port.

Tim Daley (MI)

 

[JMOR]

Might be to let the rain out........don't think there are shaft seals.

 

[Hobo,NC]

My rear 3 point lift leveling box on Rustbucket skips teeth as I try to adjust, so I figured a rebuild is finally in order. Upon tearing it down and cleaning out the old grease getting it ready to install new parts I discovered a second hole that was hidden under the grease. It is not the grease zerk hole and is not threaded. I cannot see a reason for this and looks factory not farmerized. I searched and found a post asking the same question about this second hole but no responses.

Any idea what this is for? Should it be covered with a plug?

TIA,
Dan

My guess that's the only thing you have not rebuilt on that tractor.

 

[Dan]

My guess that's the only thing you have not rebuilt on that tractor.

True! Kinda looks out of place now.

 

[Btzj02]

I have read other posts where this hole shows up. Anyone with a NAA handy willing to check theirs? The part number stamped on the housing looks like 9N565, so maybe this box was from an earlier tractor(?)

I have the same hole.