I am hooking up a fuel pressure gauge with no isolator just a needle valve & was wondering if i need to bleed all of the air out of the system, or leave it in there as a damper?

Also how would you hook the gauges up to the factory dimming switch? Is it easy to do?

 

No need to bleed.

Can't remember the fuse they tapped my guages into,
but you can tap into the ashtray light, it dims with the factory guages.


phox

 

engcogod,

FYI if you ever have problems with the gauges and they smell diesel from not using an isolator you'll likely have no warranty coverage etc.

Consider getting an isolator, the costs have come way down and it's also protects you from having any diesel fuel smell in the cab. Either way try to bleed off any excess air to get the best results on the gauge. Check our site for prices etc.

Mark @ DPPI

 

I second what phox said. No need to bleed!
What you considering is the way to go just make sure you use SS braided line compatable with diesel and you wont have any problems. I pulled the headlight switch and hooked up to the wire comming out of it.

 

I agree with mark you really should get an isolator diesel smell is pretty tough to get out of carpet.

 

Yep, no need to bleed
I didn't use an isolator or stainless braided line I did use 300psi rated hydraulic line, and a needle valve though. No sign of leaks, no smell of diesel in the cab, and nice smooth gauge action.
I also hooked up to the headlight switch wire...it made it easier to run the wires having the switch out anyway.

 

On my 01 it was a heavy tan wire coming off the headlight switch.

I couldn't find a wire resembling what the instructions described (tan with an orange tracer I believe), and the wiring diagram in Chilton's didn't jive with what I was seeing coming out of the switch either, so I just used the multi-meter to figure out which wire to tap.

 

If you are hooking up lights to guages get a add-a-circuit from autoparts store. Plugs into the illumination fuse and also works the dimmer function. Alot easier than getting to light switch. With the add-a-circuit the guages have its own fuse and the factory lights use its own fuse.

 

The guys at ISSPRO told me no isolator required for their guages.

I run mine with a needle valve and hydraulic hose straight to the pillar.

 

No isolator, no bleeding (other than my hands from the sharp edges under the dash), lights tied into tan wire at light switch.

 

In some states it's illegal to sell (but not install) a fp gauge without an isolator, that's why you get the conflicting advice from suppliers. Without an isolator is just fine, with a needle valve set almost closed any unlikely leak will be little more than a slow drip that can be shut down with the needle valve. Isolators are just one more item prone to failure, my bet is over half of them out there have failed and diesel is making it into the cab without the owner's knowledge.

 

I found a local place that hooks me up with all the compression fittings and teflon hose to make a clean and simple install, no problems here.

 

The instructions that came with my ISSPro Gauge said that if fuel is introduced to the gauge that it be mounted outside the passenger compartment... And i'm guessing the only reason for that is to save there butts in case someone would mount it in the cab and something would happen to his truck ISSPro could not be held liable...

 

Just got my DI pricol FP gauge. I'm planning on running it without a isolator. Just waiting to get the hose and fittings. Those of you that have used the hydraulic line, what size did you get. And if I splurge for braided stainless, do I get -4 or -3?

 

I used -4 teflon SS braid