Drilling and Tapping an Extra Hole in an AN Fitting

[lake_harley]

I'm re-plumbing the fuel pump and lines on my FED and need to install a 1/8" NPT fuel pressure gauge. A really convenient spot would be to drill a hole and tap it for NPT in the side of a 3/8" X AN-6 90 degree elbow. Big question is whether there's enough thickness in the aluminum fitting to get a good seal and not compromise the elbow's strength. We're only talking about 8 or 9 PSI pressure in the fuel system after the regulator. The drill size needed to tap 1/8" NPT is just a tick over 5/16".

I could add another fitting or two to provide a place for the pressure gauge, but I always figure that adding more fittings is just adding places for potential leaks.

Thanks, in advance.

Lynn 

[wideopen231]

I have about as many modified fittings laying around as factory sitting around. I have drilled and tapped for pipe or another sisz to thread into one. I have number 8 to 4 or 3 so as to run smaller lines. All are standard threads. Id doing a one into anoht a chamfering tool of  nice to have for make seat of o-rings.