If possible obtain an interrupted or skip tooth tap which will greatly reduce the possibility of torn threads:

http://www.grainger.com/Grainger/GREENFIELD-TAP-DIE-Interrupted-Thread-Taper-4CPL3?Pid=search

Tapered threads come in 2 forms which determines if sealant is required or not:


NPT - National pipe thread- requires teflon tape or sealant.

NPTF - National pipe thread dryseal(fuel)- metal to metal seal



1952 1300 Canadian 1/2 ton restomod
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