Fuel pressure gauge and pressure

[KATOOM]

29 minutes ago, wil440 said:

temporarily yes, I'd rather see what my fp is than be too worried about 15 psi of diesel in the cab, and I sheathed the pipe in fuel line and sealed both ends to the fittings to make sure it it doesn't  rub through, I work on heavy diesels all day and believe me the worst place for a leak is engine side not in the cab as about the only thing hot enough to ignite diesel is exhaust manifold and turbo.

Truck is parked now anyway as I'm ripping it all off and doing it once and for all

 

The plastic line is not so much the problem but the compression fittings.  Compression fittings on fuel lines is a bad idea.  Compression on metal isnt too bad but compression on plastic is never going to make a solid seal and can easily leak.  I'd rather deal with a leak in the engine bay long before in the cab because you'll never get the smell of diesel out of there and...its just to be clear that its illegal.  Like I mentioned, I did but I use JIC fittings and braided stainless lines.

 

On 8/29/2019 at 8:51 PM, Bullet said:

The way I look fuel pressure...it takes 14psi to open up the overflow back to the tank which means that the VP is full of fuel.  Since fuel lubricates and cools the VP then having the overflow open means that you are doing the absolute maximum amount of cooling and lubricating.  Not having the overflow open means you are doing less than the maximum.  So the ultimate goal is to have the overflow open at all times...which means no less than 14psi at all times.  Anything less could adversely affect the longevity of the VP. 

 

The overflow valve is ALWAYS open as there's a small bypass orifice in the fitting.  What the 14 psi overflow setting for the check valve does is maintain a set parameter in the second pressure chamber of the VP.  There is always overflow out of the injection pump otherwise it would cook the fuel sitting in the chambers as it waits to be injected.  That doesnt mean fuel pressure can be below 10 psi but rather that volume of fuel and fuel lubricity is as equally important as maintaining pressure.

Edited August 31, 2019 by KATOOM

[Mopar1973Man]

This why I love the ISS Pro EV2 series gauges. Fuel stay on the engine side of the firewall. Then just wires heading into the cab. 

 

Like my last install for @mr.obvious his turned out awesome. No fuel in the cab and no ferrels to crimp on plastic tubing all PTC fittings and ZERO leaks.

[wil440]

16 hours ago, KATOOM said:

JIC fittings and braided stainless lines

I have all this but it was quicker to use the plastic as it Isn't permanent

16 hours ago, KATOOM said:

The plastic line is not so much the problem but the compression fittings.  Compression fittings on fuel lines is a bad idea.  Compression on metal isnt too bad but compression on plastic is never going to make a solid seal and can easily leak.  I'd rather deal with a leak in the engine bay long before in the cab because you'll never get the smell of diesel out of there and...its just to be clear that its illegal.  Like I mentioned, I did but I use JIC fittings and braided stainless lines.

It was always just temporary just to check FP.... which I now know is too low so I now won't use it unless I really have to while I get parts together to fix the problem and I won't be hard on it until fixed

[Dieselfuture]

On 8/31/2019 at 5:38 PM, KATOOM said:

Compression on metal isnt too bad but compression on plastic is never going to make a solid seal and can easily leak. 

True, sometimes you can get brass inserts so line doesn't get crushed. 

I'm using 8th air brake line tubing and push in connectors,  been working fine for 4-5 years now.

https://www.google.com/search?q=push+in+fittings+npt&oq=push+in+npt+&aqs=chrome.1.69i57j0l3.12887j1j7&client=ms-android-verizon&sourceid=chrome-mobile&ie=UTF-8

 

Edit

I ran my line in cab but used 1/2 fuel line over the fitting that's on the gauge, 8th " line is inside of it. 1/2" line is conduit. it goes out of fire wall, so if there is a leak it will leak outside 

Edited September 11, 2019 by Dieselfuture