weak fuel pressure after crossover line

[Jeckstine]

I had blown head gaskets so I pulled the engine apart, had the heads checked and surfaced. When it was apart I did all of this also. ARP's, black onix, updated oil lines for turbo, 6.4 banjo bolts, updated fuel regulator with blue spring and I put a crossover line on the back of the heads.

At idel it reads 48lbs of pressure and if you drive it it will drop as far as 42lbs. never been up in the 60's like it should be. I could not figure out how to bleed the fuel system and I was told I did not need to. I know air will not read correct pressure. Is air my problem? Will it work its way out or is it something else?

My engine is a 2004 6.0

[RescueF250]

Replace the spring in the fuel bowl and see how that goes. The new update spring.

[bondsman]

Says he did install the blue spring. I just did mine with the blue spring and am getting 68psi. Air in the lines will give you a jumpy needle... Where are you getting your fuel pressure reading from?
How long since you did the work? How many miles since?
Any leaks??? Did you replace your fuel filters? Doubt a crossover will drop your pressure. Maybe some crap got in the fuel regulator when you changed the spring? Did you get the Ford kit and replace everything in there?

[Jeckstine]

I replaced it with the ford kit with the blue spring. Replaced everything that came in the kit. Cleaned it with carb cleaner and put back together. Both filters are new. I am pretty anal about stuff so i am pretty sure it was clean. I have a auto meter gauge with a remote sender tied into the test port on the regulator. I did bleed the sender. Saw no leaks. It worked well before the build. I have only drove it about 5 miles as i was concerned with the readings. The needle is jumpy a couple of pounds. I feal (hope) it is air in the system that needs to work out. I am going to drive it to work in the morning. I should be able to put 40 miles or so on it through the day. Maybe it will work the air out.

Thanks for any help and opinions. I called Pure Power about the line and he said it could take 50 plus miles to work the air out. i just do not want to trash the injectors with low pressure until it does!

[Jeckstine]

Drove the truck stop and go for about 60 miles today. The pressure went up by a couple pounds. needle is still jumping around. With as long as that crosover line is I would think it would hold a lot of air and take a long time to work the air out. I am trying to come up with a way to block flow to the passanger side head to alow the fuel to flow from the filter/regulator to the drivers side through the crosover and back out the front of the passanger side head. That would flush out the air but I am not sure how to do it?

[bondsman]

You could put a schroeder valve in your crossover just before the fp sending unit and bleed it that way. Just get a tee fitting to accomplish that.

[Jeckstine]

the line i have goes direct from head to head. almost no room back there with the up pipes. the sending unit i have into the test port by the oem regulator. I used the sinister extention for the sending unit.

[bondsman]

Well, you could remove the passenger side fuel line at the fuel bowl, cap off the fuel bowl where you remove that line so fuel doesn't spew out. Turn on the truck so the fuel pump kicks on. It will push the fuel through the driver side through your crossover and out of that fuel line you disconnected on the passenger side. Turn off the truck and reconnect the line.

[Jeckstine]

that was my thought. I may take it off on saturday to see if I can match something up to it to cap it.

[ajpu1983]

What was the fuel pressure prior? New fuel filters? Could have a weak fuel pump??