My dads old Ford will run when it wants to and die randomly. He says if he lets it sit a while it will fire back up and run. He also said that he tried to drain the Fuel/Water seperator and nothing came out. What on a ford goes out and causes this? Is it an electric or mechanical lift pump? Thanks.

 

I have had the fuel water seperator get pluged up with junk and I took it off to clean it. In my case the water light came on and I couldn't drain it.

If your fuel filter gets real dirty it can cause stalling. This was the case on a tractor I just worked on.

IF the injection pump is going out it can cause stalling but at that point they don't go far.

Mine was a 85 6.9 diesel and when the lift pump went bad it would loose its prime and would start had but ran ok after that. It was a mechanical pump, I think the 7.3 IDI was the same.

Change the fuel filter first, then I would check the water/fuel seperator.

 

Been a while since I have messed with these but, sounds like the IP is wearing out due to heat sink from the engine. To test this after it stalls out pour warm not hot water over IP body to see if it fires right back up. Also check for leaks in your return hoses. There is mechinical pump on passenger side of motor that I believe runs off of vacuum pump can't remeber. Also there is a site www.dieselstop.com that covers all Ford Diesel motors for further help.