So i bought a fuel pressure gauge so i can monitor my new lift pump... But the dude at Summit Racing said i need an isolator because the main pump can back pressure fuel and blow the gauge up because it will go to 200psi.... Sounds like BS! So do i REALLY need the CRAZY expensive isolator?

Using an Autometer mechanical gauge!

Thanks guys!

 

Yeah he is blowing smoke your reading psi before the injection pump, just the lp which is 15 psi

 

I think what he might of meant that the fuel gauge can get pulsation form the VP-44. I used a needle valve to dampen the pulses to my fuel gauge. So it wouldn't kill the sender my fuel guage is electric. But have seen snubbers used on mechanical guages so fuel is not brought into the cab of the truck.

John

 

Tap into it right there on the top of your filter cannister. You pull one of the brass plugs, forget which one is the outgoing side but whichever that is you want it and i think it's a 3/8 high pressure fittings or a brass fitting from the hardware store screws right into that. Connect your hose to that fitting and run it to wherever you want it to go.

You can even run to the home store and pick up a little shutoff valve if you want it also. But no you don't need an isolater unless your your tapping into the test port of the VP44 and that gains you nothin but problems.

 

I just ran mine in the cab without a isolator to the gauge in stainless steel line. I put my gauge on the steering column. You could just tap it off the fillter and run stainless steel line to the gauge you dont have to worry about air in the line with a isolator that you have to fill with anti-freeze and then bleed it. Your choice.I seen a welder weld a tank on a big rig with diesel coming out the hole. So if you are worryed about fire the flash point is very high on diesel fuel. Remember it is low pressure 0 to 25 psi depending on your fuel system .A shut off valve is a good idea if there is a problem just turn it off. I am not a welder so dont send hate mail ,it is just what I saw and was amazed.If it was gas cam2 or vp racing fuel this would be a different write up.

 

The only thing is that if you dont install the isolator - they likely wont warranty your gauge. That being said, Ive had fuel pressure guages with no isolators in both my trucks for 5 years and never have had any problem.

I will try to post some pics later tonight that are for a 99.

 

Ture with the warranty.All my gauges on my other cars have been auto meter pro comp(gel filled) gauges mounted on the outside and there still working today from (1998) and running 45 to 65 psi on them.You think that all manufactures of gauges would also make the diafram that is in the gauge to stand up to different fuels,anti-freeze,bio-diesel, diesel, water, ect,ect to last a long time.I will try to post some pics on mine.

 

Thanks for the info... I was hoping not to have to run a isolator. I will probably run a high psi hose of some sort... I cant really afford stainless... I am not too worried about a fire. I know how inflammable it is.

I actually have a gauge there already. A small one i got from Autozone. I wasnt going to use it but i had to during my diagnosis phase LATE last night. (dead LP). The guy i bought truck from updated lines to 1/2" and there is a port in the elbow on the VP. I was thinking about using that. Im all set for when i DO get all gauges because there is even a port w/ plug in it for the Pyro.

 

If you use that port down by the VP you will need an isolator or your gonna get some nasty needle bouncin from the pulses.

 

turbo20psi, do you know how to bleed the stupid isolator with antifreeze? My guage kit didnt come with and type of eye dropper thing to fill it. I'm replacing my airdog 90* line to the VP with a tapped one so I'm pretty sure I'll need the isolator.
Thanks