Ford 4500 losing prime

[HardmanGT]

My 4500 will sometimes stall when it idles too low or if a heavy load runs it down to a low RPM. To get it to restart I usually have to bleed the #2 injector at the injector. It's happening more and more frequently and trying to get it bleed out does not always work. I am looking for the solution. I don't know if the injectors need to be serviced or replaced or if there is an issue with the pump. There are leaks on the pump because it is always wet. I also am not certain that it is even timed right

Also, 2 nights ago it stalled and I left it with the fuel on overnight, it fired right up the next morning without bleeding
Last night it stalled and I left it with the fuel on again. I had to bleed #2 to get it to fire this morning
This afternoon it stalled, was a bear for bleed and it ran about 5 minutes before stalling again. I just walked away at that point and typed up this post.

Pump is a Lucas CAV
TYPE
DPA 3232978
SER 23469ZH
DFIS-22556

 

[Blueboy]

Probably a pump issue. It sound like it's getting air in the suction side. If the pump is always wet that's a good sign some maintenance is needed. Did you check for bad hoses or cracked lines? When was the last time you put filters on it?
I have no idea about the timing.

 

[Delmer]

I don't know if the injectors need to be serviced or replaced or if there is an issue with the pump.

I'd guess neither the pump nor the injectors are the problem if it dies while running. If it started and died right away, or wouldn't start, then you'd suspect the pump.

Dying while running is a blocked fuel supply, either the tank, lines or filter is plugged somewhere. A lot easier to check than the pump at least

 

[Chuck]

That sounds like you've got problems with fuel flowing from the tank to me. I'd be the filter inside the tank has gotten knocked off and you've got some junk that is sometimes blocking the tank outlet.

 

[Blueboy]

I was going to mention this is what I had in my fuel tank.

 

[HardmanGT]

Thanks everyone. I have new filters on tap and was going to change them out this morning. When I got on site it started right up and I just went to work. It never stalled today, not once. It was a lot cooler 79* vs 95* that we had been seeing. Don't know if that is a factor.

I will check the flow from the tank on. I did clean the tank, petcock and filter out about a year ago and I don't use this very often so who knows what I may find.

 

[4500GUY]

Sounds like an issue I have also. I have determined that it is a pump issue on my machine. Hot starting is very difficult. When she cools off she will start right up. What is happening is that when the fuel heats up it becomes much thinner and the pump rotor just can't pick it up and build enough pressure. This pressure is essential in order to fire the injectors properly. As a test, put some water from a hose on the rotor part of the pump. If she starts right up, you know it is a pump issue. The fix for me is a rebuilt pump. Good luck!

- Dave

 

[Delmer]

Put cold water on a hot pump at your own risk!