I'm going to get an Isspro mechanical fuel pressure gauge without the isolator. I'm just wondering what inlet fitting it has on the back so I can figure out my plumbing?

 

Might depend on which guage you use....Isspro EV Series is 1/8" FNPT

 

Oh yeah, didn't think of that. Planning on the Isspro R5604R Enhanced Visibility Fuel Pressure Gauge 2-1/16" 0-30PSI from Diesel Manor. Is that the one with the 1/8" FNPT?

http://www.dieselmanor.com/isspro/r5..._fuelpress.asp

 

Yup - thats the one I have and its 1/8" FNPT thread.



BTW, if you order from Vulcan, they will be able to set you up with everything and should know exactly what you need.

 

Dr. Evil,

I edited that. I found that on Diesel Manor, not Vulcan. Looking at Vulcan too, but they only offer the gauge with the isolator.

 

Legally I think they have to sell you the isolator. That does not mean you have to use it. Mine made a 1 way trip to the garbage dump about a year ago. I had some issues threads leaking, I found some diesel thread seal and all is now well.

 

Well, I found just the gauge for $40 on dieselmanor. With the isolator it's $128. Since I'm not going to use an isolator anyway I didn't want to pay for one. I'm going to put a needle valve on the banjo and run braided line into the cab with a bulkhead fitting on the firewall. The gauge will be mounted under the dash and the only connections in the cab are going to be the one tying the braided line from the bulkhead fitting to the gauge.

 

You dont need the bulkhead fitting - just another place for it to leak.

 

Ok, I was debating on whether to use the bulkhead fitting or just put a grommet in. The grommet probably is a better idea, 2 less connections...

 

My Isspro FP guage leaked after not to long. I wouldn't put it in the cab if I were you. Thanks Steve B.

 

Where did it leak at? The guage itself? or the fitting?

 

FWIW, Ive been running Isspro EV's for 5+ years (one 30 psi on a 24V and one 60 psi on a 12V) and its never leaked a drop.

 

The guage itself leaked, somewhere on the inside of it. Thanks Steve B.

 

Ok, I was just curious. I've heard a lot of good things about the Isspros on here. I think yours is the first one I've heard of leaking. I'm not too worried about it as I'm going to have a valve right at the banjo I can shut it off with if it leaks.

 

You dont even need to drill a hole for a grommet - the hole is already there.

Im not saying guages cant leak - there is a very thin metal tube (bourdon tube) inside the guage that translates the pressure it sees to the numerical indication - but most mechanical guages need to be seriously overpressured for a internal bourdon tube to become ruptured.

Heres what my 12V setup looks like: