Grease Zerk Tap size

[johninct]

I want to make sure I know what taps to use for grease zerks.

1/4" -28 NF for the smaller fitting,

Next size up 1/8"-27 PTF. Is this the same as 1/8"-27 NPT?

Next size up 1/4"-18 NPT

 

[dayid]

Next size up 1/8"-27 PTF. Is this the same as 1/8"-27 NPT?

I believe from this archived conversation that you can interchange them to extents.

This is also worth a look.

 

[Provincial]

There are also metric zerks, so be careful!

 

[SVE Performance]

NPT and NPTF in this application would be interchangeable the difference between the two is that NPTF doesn't require any sealant to seal. In automotive applications most often seen in the inlet fittings on old carburetors .Bill