Is it worthwhile to have a fuel pressure gauge or just set it and forget?

[Rodney]

I've been doing some research and this is what I've discovered.
Temp fluctuations during shipping and in the process application cause the liquid filling to expand and contract which in turn increases or decreases case pressure. As a result, accuracy can be decreased and the pointer may not return to zero properly until the gauge is vented to atmosphere.
To vent a liquid filled gauge, simply cut the top part of the rubber nipple plug on the back side of the gauge. This allows the case pressure of the gauge to be equal to atmosphic pressure. Also make sure the gauge is installed in the upright position ( nipple at the 12 o'clock) to prevent leakage of the glycerine or silicone.
Give this a try and your liquid filled gauges will work as intended! Hope this helps. Rod