I am in the process of putting guages in my truck and i was wondering what type of fuel pressure guage would be the best. I have heard that the electric guages are not very acurate but not sure if i want fuel in the cab of the truck with me or not. Just wondering what you all did. Any suggestions will be helpful.

 

I plumbed nylon tubing straight to the gauge with no isolator. Actually I do have a isolator "needle valve"...

I've had no leaks so far... Except one that was my fault for not tighten all the fitting on the gauge tight. But the needle valve allow me to shut down the gauge and tubing till I could repair/tighten it...

Trust me you will smell the diesel as soon as the first drip starts in the cab... All it did was pool in the pod and never ran down in the dash...

But after that I've never had a problem with diesel in the cab... So the needle valve did its job...

 

I run diesel straight to the gauge too......I just used some -4 steel braided hose and fittings from the needle valve to the gauge.

 

How long of that steel braided hose, and what kind of fittings and which needle vavle did you hook that up too. or did you move one of them to the bottom of the fuel filter housing like i have seen quite a few people doing. Do you have the stock lift pump style or did you upgrade to aftermarket. What kinda fuel pressure are you running

 

Please do use and electric or isolator. Especially with the high vibrations these vehicles have, you would not like to have fuel spray all over.. not only that, mechanical gauges do fail over time.. and can spray out the front.. even worse would be a leak that gets ignited by the guages lights...

not worth the risks, isolators arent expensive.

 

Mechanical gauges fail over time? I suppose anything can fail but I have only ever used Autometer Sport Comp gauges and have not had one failure with any of their mechanical gauges.......Some are 12 years old. Isolators and diesel fuel are another story - they can break down over time and you will never know there is a problem....other than the fact that there will be fuel at the gauge instead of glycol. Diesel fuel vapours have a very high flash point compared to gasoline and is a relatively low risk for a fire hazard.....a hot light bulb in a gauge will not ignite diesel. Don't get me wrong, nobody wants a diesel fuel leak in the cab but with high quality gauges and plumbing, the risk is negledgable. Gasoline fuel pressure gauges must use an isolator as the vapour has a very low flash point making the risk for a fire very high. I use isolators for the fuel pressure gauges in my Jeep (Gas) and they work well but the rubber diaphrams in them don't appear to hold up to diesel well......I suspect Autometer and others will probably being coming out with a diesel-safe isolator soon.

 

I used some Earl's 4 AN teflon lined braided hose and fittings ( about 4', I think).....the needle valve was included in the Scotty Smartfuel kit and I connected it to the fuel filter housing with some 1/4" hardline.

The pic shows the the hardline to the needle valve and the braided hose coming out the other end of the valve that goes to the gauge.



I run the stock Carter LP and have 9 psi at WOT with the Comp on 5x5 and 12.5 psi at cruise.

 

I just put in autometer isolator and z series mechanical gauge. they work great. my brother in law put in an electric gauge in his rig. ran braided line from isolator up to fuel gauge in triple a pillar. Running 15+ psi at idle, and 12 psi at wot.