Help identifying Countyline RC5 gearbox vent plug

[CopalisFarmer]

I was given a 5’ Countyline brush cutter, square back, that has had a rough life. It doesn’t look pretty but works. But due to the previous owner’s abuse of it, there are next to zero identifying labels on it, or the gearbox. We recently lost the vent plug on the gearbox and I have no idea how to find the replacement part. I called the local tractor supply store and they weren’t able to help.

So, two questions for this group:
1) anyone know the part number of the vent plug?
2) since I can’t find a model number on the gear box. Does anyone know how I go about measuring the hole and threads so I can track down a replacement part?

If I had to guess, the brush cutter is at least 10 years old.

Thanks!

 

[Southernspeed]

I believe they are made by Tarter Manufacturing, could be worth contacting them for info or maybe even the vent plug if they have a direct parts sales counter.

 

[WranglerX]

Is it a vent or just a plug?

Could it be a 1/2 of 3/4 inch NPT plug?... Pretty common for equipment manufacturers to use this style plug....

 

[Halftrack]

Find the correct size NPT (common hardware store pipe fittings) plug in either steel or plastic, then drill vent hole in it, just slightly larger than a short cotter pin. Insert the pin and spread the ends, plenty of venting and very little leakage. If you want the real thing, check Surplus Center for breather plugs.

 

[CopalisFarmer]

Thanks for the suggestions! Picked up a couple different sized npt plugs from Home Depot to find the right size. For anyone else in the future, that model use 1/2” npt. Plenty on eBay for a few bucks, search for “1/2” pressure release valve”