I bought a 0 to 15 lb mechanical fuel pressure gauge and was going to install it but wondered where the rest of you have tapped into the fuel line.
I was thinking of cutting a chunk out of the metel line from the fuel filter to the P7100 pump work. I was just going to splice in a brass T fitting and use 1/4 I.D. rubber fuel line hose.
I heard some say they used a length of rubber grease gun hose and ran this into the cab. Is the regular rubber fuel line hose that I was thinking of using too soft or expand too much?
What is the most pressure I would see?
Thanks guys,
Matador

 

First of all your 15 gauge won't even read the minimum FP on a 12 valve, you need at the very least a 40 psi gauge, 60 psi is best.

Easy way to tap in is to remove the injection pump inlet line banjo bolt and tap a 1/8'' port in the top of it. Teeing into the fuel line sounds like a leak waiting to happen.

You will need to use a gauge snubber or needle valve shut almost all the way right after the banjo bolt or the pressure will pulsate so badly that the gauge will be unreadable.
I use regular ol' boost gauge 1/8'' tubing from the needle valve to the gauge in the cab. Push it though a larger size tubing (1/4'') to protect against sharp edges and kinks.

Needle valve installed in banjo bolt

 

What is the maximum pressure I should see? What does yours say at idle and then a full throttle?
Thanks,
Matador

 

Mine reads about 22 psi at idle and a max of 38 psi at full throttle.

 

I see I need a different gauge.
Matador