Testing fuel pressure

[94turbocrewcab-lb]

Im
Over in Brooklin...maybe 9 minutes from Blue Hill

 

[IDIBRONCO]

I need the fuel heater though..-25 is pretty cold

There's debate on whether or not that heater actually does anything in the first place. It sits at the highest point in the entire (stock) fuel system and, as we all know, heat rises. While the engine's running at -25, it may not be accomplishing anything at all. The better fuel heater was the 6.9 version that was a part of the hard line that runs between the lift pump and the fuel filter. At least there all of the fuel has to pass though/by it. Another thing to add: after almost 30 years, is your fuel heater even still working?

 

[Nero]

Funny you mention the 6.9 heater, the dud engine I pulled out of my dad's CC had said heater line on it, and I'd never seen it before. Yes it still works too lol

 

[jrollf]

There's debate on whether or not that heater actually does anything in the first place. It sits at the highest point in the entire (stock) fuel system and, as we all know, heat rises. While the engine's running at -25, it may not be accomplishing anything at all. The better fuel heater was the 6.9 version that was a part of the hard line that runs between the lift pump and the fuel filter. At least there all of the fuel has to pass though/by it. Another thing to add: after almost 30 years, is your fuel heater even still working?

My understanding was the only purpose of the filter heater was only to prevent wax crystals from clogging the filter... of course if it's cold enought for diesel to gel/wax, it's debatable that the pump would even be able to suck it from tank through the strainer.

 

[Booyah45828]

I tested mine at the bleed orifice, if you still have it. A simple vac/pressure gauge for a gas engine and about 10 foot of rubber vacuum hose. Harbor freight had them for less then 20 bucks last time I walked through the place. Zip tie it on the barbs if you're worried about the hose blowing off. Plug the return hose to keep it from leaking. Then if you really want to test more, plug the bleed orifice and test your return system pressure, as anything showing on that will also cause poor running.

FYI, check pressure at idle, while it's running down, etc. as fuel demand will vary based off of running conditions. Pressure should be 5 psi or so. Just because it's sufficient at idle, doesn't mean it is at full throttle. A lot of the facet guys found this out after swapping them in.