I'm getting ready to plumb a fuel guage & have of course been researching details. Many have said that they haven't had any trouble (for 6 years whatever) using plastic line into the cab. I've got a Mercedes diesel & the 1/8" plastic vacuum & boost lines have become brittle. My point: at some point these lines become a maintainance item & should be replaced.

 

First post, wow!
Welcome aboard.

Yes I imagine everything wears out at some point, but the reason I don't like the plastic line is because I always manage to kink it, and if you tighten the ferules too much they leak. Instead I use 1/8 copper tubbing, of coarse it is harder to bend and you can't run it directly to the engine because the vibration will make it crack over time. So what I do is run a 30" length of high pressure rubber hose from the fuel pump to somewhere on the fender, and from there I run the copper tubing to the gauge inside the cab.

Oh, in case yo don't know, don't run an isolator, they are crap, and sooner or later you'll end up taking it off and junking it.

 

Wise words

that isolator is a POS for lack of a better term, do away with it, and save your money. Im runnin an oil pressure tubing setup for my FP gauge (1/2 of it is braided steel line) and i havent had problems, just watch where u route the line....

Rick

 

If you thread the smaller line though some 1/4" tubing it won't kink, get cut or abraded. 1/8" boost type tubing is made of all kinds of different materials. The airbrake type I buy by the foot from Napa is just as flexible now as it was almost ten years ago when I installed it.

As far as ferrules leaking when overtightened, well duh, you can break your wheel studs off if you reef down on them also.