My 7.3 Diesel is fuel starved. It acts as though its running out of fuel. I tried dropping the tank to see if it was a pick up tube problem, saw a disintegrated screen, replaced it, but no better. I fill up the fuel filter res with fuel, start it up, and it will drive about a quarter mile before running out. Put in new fuel filter - no change. have good pressure in the outlet next to the fuel filter until it starts to starve. Thinking about the transfer switch for the tanks. thinking abut bypassing them, but don't know where to get the hoses and have been advised not to cut them. I don't want to replace the fuel pump unless I am sure that is the problem, besides, it seems a little out of my league. Any suggestions?

 

Check fuel pressure. Replacing the pump isnt hard.

 

What exactly did you replace on fuel tank pickup?
Those engines do have tank strainer, than fuel mixer with fine screens, that are common for clogging by fuel residue. Here are mine for comparison. The top would not let the fuel go. Notice there is no heavy dirt on it - just shellack like residue

 

Thanks for responding. The filter in you photo is on th side of the fuel filter assembly on the top of the engine. Mine seems fine. There is no air restriction when I blow thru it. The screen assembly that I replaced in the tank was a relatively simple part. There did not seem to be any secondary type screen in the tank. The only screen that seems possibly to be clogged was in an assemly that bolts to the side of the fuel filter housing. It is about the size of the thimble with a circiular screen a little smaller than a dime. This part has a very small hole in it. It is difficult for me to determine the purpose of this part or if is causing my issue. It is not available locally. Besides, I doubt that is my problem. I cleaned it out with no change in the motor's behavior.

 

How do I check the fuel pressure?

 

If you don't have the filters I pictured above in your tank, that means PO deleted them (quite common) and you should have aftermarket filter on the line somewhere.
How about a picture of the device you have on the side of the main filter?
Check the line before fuel pump for other filters.

 

I do have that filter, but it is located on the side of the assembly at the top of the motor. Is one possibility is the tank transfer switch? I am thinking about bypassing it. Your thoughts? I will try to post a photo.

 

I could not locate any other filters other than those I mentioned.

 

7.3L PSD - How To: Measure Fuel Pressure - YouTube

 

Awesome video. Thanks. My truck has a schraeder valve installed. I don't have a gauge, but after I filled the filter bowl and started the engine, then stuck a punch in the end of the valve, ample fuel pumped out of the schraeder valve. The flow decreased as the engine became fuel starved again. If I fill up the filter bowl, the truck cranks with no problem, but it will only run for about a half mile. Is it possible my tank transfer switch has malfunctioned? The truck sat up for a couple of years before I recently put it back in service. I believe my truck has a mechanical fuel pump. I went to the dealership w/ my vin number and got a diagram showing a mechanical fuel pump located below and to the right of the fuel filter bowl assembly. In addition, I have not been able to locate an electric pump.

 

So your 7.3 is older than 1999?
That is why we can and should put our trucks in the profile.
Go down to diesel section with your engine model for more precise help.

 

yes. I have a 95 F450. I hate to start all over again in another section. I am somewhat new to this type of collaboration, and may have ended up in the wrong section. However, this problem should be diagnosable by someone with your knowledge. I feel like I am close to an answer and hate to start over.

 

Can a moderator please move this to the correct forum.

 

Moved to the correct forum.

 

Does it do this on both tanks?