Originally Posted by Southtowns27
What thread is on the back of the factory AD oil pressure gauge?? I have a whole mess of fittings here and none of them fit. How does this work?

Had a whole bunch of fittings on mine when I bought it too. The oil guage thread size is 1/16" NPS. It has 27 threads per inch, the same as an NPT thread, but the oil guage boss is a straight rather than taper thread.

Stuart.

Last edited by Stuart_Giles; 04/18/2012 1:51 PM.
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