Grease zerk size?

Mark-Mi

Well-known Member
Location
S.E. Mi.
I could use some help on identifying what size and thread pitch the grease zerk on the left is. It is smaller than the two 1/4-28 zerks I have in the picture with it.

The zerks came out of a 1940's Knoedler seat that I am rebuilding. Thanks, Mark
a184013.jpg

a184014.jpg

a184015.jpg
 
Is that a "drive-in" zerk, or does it actually have threads?

Check out various drive-in and threaded zerks at the link below.
McMaster
 
Check and see if it is a 10-32 grease zerk. They used to be common on some brand of aftermarket stuff. I think I have some old assortments that had them in the sets.
 
That may be a drive-in zerk. What looks like threads are often just made to hold it in and then there's the space under the top lip.

You might also check that it's not some metric replacement someone stuck on. I've been fooled a number of times on zerks, bolts, & nuts on what should've been an old std size had been replaced at some point with a metric size someone had in their part or bolt bin.
 
Tractor been in family since new. Grandpa never heard the word metric. Zerk has hex on it and screwed out. Thanks, Mark.
 
WHOA...it is NOT a drive fitting. They do not have any way of screwing them in such as 5/16 wrench. They have just a round collar with no faces. Some have said metric, old style thread, or There are 1/16 pipe thread fitting but rare. I use drive fittings and they work very well if you know how to install them correctly. Look at the grease fitting rack at tractor supply. They carry 5 /16 drive on a card. You can get four different sizes of them.
 
Just a thought, You might put the suspect zerk in your pocket and take it to the hardware store and see what size of NUT it might thread into like 10-24 or #12 or 1/4-20 or 10-32. That is provided it is not tapered pipe thread like some have said. I know 1/16" NPT pipe thread is out there but in my 30+ years of experience with machinery and tube fittings I think it's a pretty rare thing. Good Luck!
 
Guys I am still stumped. Not 10-32 tried tap and die and my thread checker set. Zerk to big.

Not many threads to go by but does look like it could be 27 pitch according to my pitch gauge. But online shows 1/16 pipe OD to be .313. Zerk only measures .205 across threads. I will go to town tomorrow and see if I can find some 1/16 pipe fittings to compare to.

I like a good challenge, but I may have to throw in the towel and bore out to 1/4 zerk or weld a nut on.
 
After the 10-32 was mentioned, I was wondering if it was 12-24, as it looks too close to the 1/4" fitting to be a #10. But I guess not, if it's 27 TPI.

If you end up making the alteration, I would go with welding a nut on. I have seen similar situations where the stinking zerk will bottom out against something before it's tight in the threads.
 
If you have a good NAPA or other auto parts store, take it in and see what they can come up with. My local guys will look for a long time even for that one dollar part, keeps me coming back.
Other thing is find manual with the seat , maybe have a part number or size for it. luck joe
 
Get your tap and die set out and see which die it screws into. What's wrong with that one?
Soak it in atf for a day and heat it up with a zippo.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top