It seams the fuel pump puts out 4.3psi and if the return to the tank is plugged it may flood the carburetor.
By the way NAPA sells the separator at a lower price.
You might want to check out these two threads also.
Good Luck

From Thread
https://www.ford-trucks.com/forums/s...apor+Separator

This is not an option. It comes standard with the 460 option.
The fuel pump in the tank is a low pressure pump capable of 25 gph @ 4.3 psi. It sends fuel to this little gizmo by the carb called the vapor separator. This works by pressure. What the carb doesn't need, it sends back to the fuel tank. The idea behind this is it keeps a constant supply of cool gasoline available to the carb available at all times eliminating vapor lock and other maladies.
Remember, these trucks were built to work!
Good Luck!


From Thread
https://www.ford-trucks.com/forums/s...apor+Separator

iskerbibel

I cut one of those open on the '84 f-250 that I had... it just had an orface to restrict flow back to the tank- nothing else. I brazed it back together and it's still on the truck.

I had thought that the problem might've been that thing, but it turned out that some rocket scientist had re-wired the fuel pump, and they ran if off the coil wire... so not only was the current running to the pump through the factory resistor wire, but also through the ballast resistor, hence not enough fuel flow.

8 Lugs

The part is called the vapor separator.
The dual line set-up is called "Hot fuel handling"
It is designed to keep a supply of cool fuel available at the carburetor by returning fuel heated by high underbody temps back to the fuel tank, thus eliminating vapor lock as beetle pointed out!
The fuel pump produces 4.3 psi.
The vapor separator also reduces pressure to the carburetor by returning fuel to the tank.
If one plugs the return line this will over pressurize the carb needle/ seat assembly and possibly flood the carb.
Also it will deadhead the pump and prematurely wear it out!
Good luck!
Reply With Quote

 

Again, I can't thank you enough.I never did buy a fuel pressure gauge because of the price and I may never need one again.But,I decided to troubleshoot the wiring again and found the problem.The wire from the oil pressure switch to the fuel pump relay was broken,thus no fuel when running.I have 3 different separators(2 from Ford,1 aftermarket) as for idling in the driveway the original seems to work the best even though I opened the return orfice to about twice it's original size.It seems to be getting to much gas,but I haven't test driven it yet and will try adjusting the floats accordingly.I have taken some pics and will post them if they develop ok in a few days.I may start another thread just to tell my story about the repair to help someone else who may have this problem in the future.If I post the pics there I will let you know.Thanks

 

Here is a Diagram of that system if you ever need it.

 

I think i am having this problem. I have changed everthing but it and it is the last thing to change. Buy the way. I have a 85 F-250 with 460 4-speed 4x4. I put new fuel pumps in both tanks. I want to get rid of the front tank so i can put a better dual exshuast sys. I took off the fuel tank selector switch and noticed both lines where pumping when i switched it in the cab. I am goining to try to take that part off and run some carb clean threw it and maybe a pipe cleaner. Do you have a part# on that 4 core radiator. I am sure the color code is gone buy now. what one do you think i should start with. Thanks for the help.

 

I do not know of a cross flow four-core radiator that will fit your Truck. Mine had a C6 and the fuel system was not the system above as it was a 1982 E350. My radiator in an E350 was not a cross flow.

 

Is it the fitment of it or just the wrong configuration?

 

It would be the fitment.
Both are MODINE Radiators That all OEMs use.
85 E 460 4 Core = MO 2195
85 F 460 2 Core = MO 2183

 

subford, I cannot post attachments.I have a couple of pics of the separators if your'e interested and would like them you'll have to e-mail me,so I can send them to you. aldog3@yahoo.com

 

You have specified that they do not wish to receive emails in preferences on this site so I can not email you.

You can email them to me at:

subford AT gmail.com


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