No start, no fuel pressure.....

lmorris · September 6, 2011

Early build 98 E350, mechanical fuel system. No start, no fuel pressure at regulator block. Fuel bowl is filling. Has new pick-up in tank for fuel gauge issue. Along with new engine it got a new fuel pump and the fuel bowl was inspected and cleaned. Regulator has not been replaced...yet. Engine ran for about 45 seconds on initial start-up then stalled. Checked for fuel in filter housing and was full. Checked fuel pressure cranking-none. Though air lock, so I removed the schrader valve and was getting no fuel. Placed a clear looped hose at the inlet of the pump and it pulls fuel but will not fill the loop with a continuous flow. Not sure if this is normal when cranking, only performed this test when running. The engine did run on occassion when it came to us with the request for a new engine to be installed.

Edit: Starting to think I caused this.... Posted Image .... During my repair of thre fuel gauge issue, I noticed the tank had been dented where the pick-up sits. The tank has been shortened to make room for the transfer case, it's been converted to a 4X4 ambulance, so a new tank was considered but not installed because it would have to be sent out and shorted also. I didn't attempt to bang out the dent because of the plastic slosh plate, and didn't want to chance damaging that. So I shortened the pick-up tube on the new sending unit, with my SM's blessing. I think now I didn't shorten it enough and actually caused a restriction.

Out comes the tank once more..... Posted Image

Keith Browning · September 6, 2011

Well do let us know. Some of these bastardized vehicles can be tough.

lmorris · September 6, 2011

After taking out the tank, which is clean inside BTW, i realized I didn't shorten the pick up enough, thinking that was my issue, I knocked another 1/2 inch off the tube and it fits nicely in the tank, so back up she goes. Pressured up the tank with the line off before tighten up straps and lots of fuel spews out the line...I am happy. Connected everything up and left the tank loose. Crank the engine and nothing. Blew out all the lines, didn't think to do this first because the tank was clean. Now I can get fuel up to the engine, but it doesn't seem to flow very fast. Got a smallish container of diesel and connected it directly to the pump, It emptied that sucker fast, so charging up batteries once more and going to see if this thing will run off a gerrycan of diesel. Will update later.

BTW...found out by shear luck that the 6.4L EGR cooler tester block off plate is a perfect fit to block off oil feed to the turbo, so I could crank with the turbo off, gives me full access to the entire fuel system.

Jim Warman · September 6, 2011

Instead of pulling the tank on a guess... why not check inlet restiction to see if there's a need? Tee a compound gauge in between the pump and tank... recheck with the pump outlet open if necessary.

lmorris · September 6, 2011

With the smallish jar of diesel running to the pump I was able to get 50 psi cranking and bled out the air from the heads. Put the turbo back on and hooked up the lines to the tank and she runs, but fuel pressure hits 80-90 psi then drops to 30. Since the entire fuel filter assembly is $100 cheaper than a new regulator, it gets an all new filter housing to compliment the new pump. Tommorrow I roadtest....cross fingers.

Keith Browning · September 7, 2011

...the entire fuel filter assembly is $100 cheaper than a new regulator...

More Ford stupidity. Remember when you could get a fuel pump for and HFCM on 6.0L F-Series? The pump was more than the entire HFCM! The pump has since been discontinued but man! Some things make no sense.