Hello guys (gals if there are any) I've been away for a will but find the need to return because I've exceeded my knowledge. I have a 7.3 dually which I'm in love with. It would stop on me often so i had the engine changed. It sat for almost a year. I would drive it and it would run out of fuel. Changed the fuel pump and the other day I took it on a road trip, drove fine for about 60 miles, a good distance. On my way back home, the fuel filter idiot light came on. It sputtered home and shut off. Change filter, put fuel in the bowl, purged air and took it on a short test drive. Under normal load drove ok. I decided to punch it, on the way back home. It stalled and shutoff again. I followed the same procedure, put fuel in the bowl, starter fluid, purged the air in the system. Did this several times. Today, followed the same procedure, and let run idle for about 30 minutes. Runs fine in the yard. Starts up normal, but I'm afraid to road test, tired of being pulled home. WHAT IS HAPPENING? Frustrated. Please help.
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Have you checked this?Scroll down to page 4 of 9 and read about the screen between the housing and the FPR.

http://www.dieselorings.com/docs/OBSFuelBowlRebuild.pdf

 

After I changed the engine, during a road test, the "Water In Fuel" light came on. The truck shut down. On Thanksgiving, I swapped the fuel bowl with the bowl from the replaced engine. As my original post indicated, the truck ran fabulous until what I described occurred. Today, I will ensure that they are the same bowls and repair the one original to the engine I installed. Can you tell me is the O-ring repair kit a product I can buy from an AutoZone or Advance? Or do you recommend I go to, as someone called them, the "stealership?"

By the way, I was reading another post and I've check the pressure at the sharder valve while the truck runs at idle. The fuel pressure is just under 50 psi (each time I tested it I could not see 50 - measured in the high 40s). Does this information change anything with your diagnosis? I'm still going to rebuild the bowl though, I think that will be worth it.

 

These internet diagnosis and fixes are tough sometimes.My mind is on lack of fuel right now but I will ask if you have checked the UVCH?It is known to wiggle loose and it will cause problems as well.
You can get the best bowl rebuild kit form Bob(Guzzle).It will have everything in it and he has super fast shipping.
Is the CPS new?
Replacement O-rings for Ford Diesel Engines

 

The CPS is new (an AutoZone part). Thought about putting the old one back in. As I said, last night, I got it started and it runs fine idle. Later today, I'm going to get the nerve to test it on the street. I also will check the under valvecover wire harness for broken connections. But would the UVCH go without notice? Will road test and let you know.

Thanks

 

Some folks have had trouble with local parts store CPS's.Black is the favorite one and grey the next favorite.Check out this thread on UVCH and chaffed wires on the 42 pin connector.

https://www.ford-trucks.com/forums/9...rpms-long.html

 

Will do on the thread for UVCH. And will remember the tip on the CPS.

 

Don't mean to sound ignorant, and I know that many shutdowns have been linked to the CPS. But will the CPS just fail and then allow the vehicle to start again. What I'm noticing, is that when it does stop and I open the fuel bowl to check the filter, the bowl is literally empty. I put on a new fuel pump on thinking that the first one was failing. Is the fuel pump suppose to keep the fuel bowl full with diesel? Is there a way to test the mechanical pump for failure? Because I was sitting about 8 months, could algae have built up in the fuel system and clogged the pump. Before I install the new fuel pumb and drove it for the road trip (refer to original post), I blew air in the tank and fuel pumped thru the line (mechanical pump was not connected). Put new fuel in and off I went. Could I be catching air somewhere thru the fuel system? I know this post has quite a few questions, but that is the extent of my mindset; I don't have any direction in resolving this issue.

 

I have been paying close attention to your posts.I am still thinking fuel but I was giving you other problem areas we have seen with these symptoms.The CPS will act the way you are describing.You can make a turn and the truck will die but start right back up.You can have studder at take off.Go pedal gliches.These are all classic CPS issues.
Back to fuel....That screen on the fuel bowl should be checked.Does the double fuel tanks have socks/screens in them like the 99-03?Any kind of screen/sock in the tank can get stopped up with gelled fuel or trash would cause the fuel bowl not to stay full....We must concider another bad manual fuel pump.I know some of the OBS owners have deleted the manual pump,installed a cover where the plunger goes on the cam and put in an electric fuel pump.

 

I will do as you advise Mr. Fish Hunter and reply again. If I have to install an electric pump, where would that go. But that may be too advanced for now. Hey thanks for your help and if I may say concern. I will post my response to what I find soon.

 

You are most welcome.I do not claim to know it all but willing to help.Maybe other OBS owners will chime in as well.
What are you finding in the fuel bowl when you change the filter or it runs out of fuel?

 

How much fuel in the tanks? If 1/4 or less then strainer in bottom of tank might be algae up. If so fuel will be pickup up above there and when tank get 1/4 or less you will start sucking air. Or strainer in bottom of tank might provide enough flow at idle but enough restriction at more throttle where it can't keep the fuel bowl full.

 

^^^ I agree with Jim.It sure sounds like fuel starvation with medium to heavy throttle or under a load.

 

can you mash it from park and get it too stall? if so thread on a fuel pressure guage from the side of the fuel bowl at the shrader valve and see if its dropping fuel pressure enough to be the stalling.

 

It started this foolishness on about a 1/4 in the front tank then I switched it over to the rear. I guess I will drop the tanks Saturday and check.