I'm in the process of connecting up my '74 MGB-GT's mechanical oil pressure gauge to my '61 Buick 3.5L's oil system. I have a question. Does the tubing from the pressure gauge to the oil pressure source need to be filled with oil? I seems to me that it might but I have no idea how one would do that. Thoughts/comments?
Not necessary.
Carl is absolutely right. No need to rid the air from the tubing. It might even be detrimental if you're using 1/8" tubing. A cold viscous oil in that small tubing would dramatically slow the response of the gauge vs an air filled tube. But really, if your gauge hits zero in 1/2 a second or 3. your screwed either way.
Cheers
Fred