Thread taper-lubricating nipple M101A1 from 1953

[Sezzo]

Does anyone know the exact thread size of the taper-lubricating nipples on a M101A1 from 1953. Two of them need to be replaced on my trailer.

Thank you in advance.

Best regards

 

[NDT]

I think you are talking about grease zerk fittings and those should be 1/8 NPT.

 

[frank8003]

The patent 1697217 for the Zerk fitting was granted to Oscar U. Zerk in January 1929, (01011929) and the assignee was the Alemite Manufacturing Corporation[1] (thus the eponymous names for the fittings). Alemite had already been marketing, since 1919,[2] ball check valves to accept grease supplied under pressure from a grease gun, such as for car and truck chassis lubrication points, both for OEM installations and for aftermarket upgrade kits which would screw in as replacements for stock grease cups, but Zerk's fitting was an improved style, less vulnerable to dirt and more forgiving of angled approach. Today, many companies make these grease fittings.
https://greaseextensionhoses.com/grease-fitting-thread-identification/

 

[Sezzo]

Thank you. The size of this thread is what I need to know. Is this really 1/8“?

 

[frank8003]

Thank you. The size of this thread is what I need to know. Is this really 1/8“?

maybe read what is in the link I posted above?

 

[Sezzo]

maybe read what is in the link I posted above?

I did, thank you. Just want to be sure. Looks like a tapered thread - it is really hard to see.

 

[Sezzo]

Ok it seems to be 1/4“-28 tapered thread.

Thanks guys. Thumps up!

 

[NDT]

Agree, that is the smaller grease zerk and it is not 1/8 npt like I said.

 

[frank8003]