Gary, I've never seen a hot fuel vapor separator mounted to the frame.
I do realize that is where the frame hard line ended and short sections (feed & return) of rubber line allowed the engine to move in its mounts.
It was then hard piped up to between the coil and distributor

I'm pretty sure the idea is to keep some fuel pressure until past the radiant heat of the exhaust manifolds, but I'm not the engineer.

 

Hi Gary,

yeah, my plan was to get the electrical system up to speed so I could drive around. My odd work schedule , 4 months over seas / 4 months home forced some decisions that I wouldn't have made if home all the time. Also I frequently would get called out for emergency jobs if something was going on with the military where it looked like we might have to deploy the Marines Corp, called out for exercises, etc, etc so when i would be home was somewhat unpredictable... so wanted the electrical fuel pump system 100% just in case it had to be in longer than planned.

So my intention was to get the electrical fuel system working good and reliable, than at an appropriate time switching it to a all mechanical fuel delivery system. I think somewhere in those notes or maybe at a internet link there is some info on a job some guy did this on his 460 putting in mechanical fuel system and was switching between tanks with a machined brass block and brass valves... It was real elegant and trouble free, I really liked it... so some parts where in the box for doing that

V

 

I have a Carter mechanical pump on my 460.
Despite what disparaging things some people say, I am *still* using the 30 year old six port factory switch valve.

 

Jim - I'll have to look more closely as I assumed that was the factory location, but perhaps not. I know the fuel leaves the tank and returns in the plastic lines, so I thought those line ended at the fuel separator. But, I hadn't thought through that there's a switching valve in between and the lines from the pump surely stop there and I don't know what kind of line runs on to the separator.

If it is rubber lines, what do you think of replacing the separator with the return-style pressure regulator that Vernon supplied? I could mount it forward, like I've done with the dead-head style, which would have it past the heat of the headers.

Vernon - The 460's generate so much heat that Ford had problems with the fuel turning to vapor. Pumps can't move vapor, so they changed to in-tank pumps which were pushing relatively cool liquid fuel. But even then there were problems with vapor so they added the hot-fuel package that is a return system based on an orifice. So, some fuel was circulating at all times, which helped keep things cool.

You supplied the fuel pressure regulator, but it is a return-style which means it has to have a return line back to the tank. In other words, it needed to go where the separator is down on the frame, but there wasn't room nor time. And, as Jim points out, having it there would defeat the purpose of ensuring cool fuel makes it to the carb. So I installed a pressure regulator designed to work without a return line just to get the truck running but not have another full crankcase.

Now I have to figure out what the best approach is for the long term. I need to rewire since the factory fuel pressure relay has been neutered and the pump runs all the time. But, I don't want to start making changes without a view of the overall plan. And, that plan may be influenced by the parts already to-hand.

 

Wait - are you saying you don't have fuel problems with a mechanical pump? Maybe I need to rethink things.

 

Im not an RV spending hours trying to climb a pass or towing heavy and stuck in a highway traffic jam in August.
I've not encountered vapor lock in the 30 years I've had my truck.
But that is *only me*

What IS a problem is getting the pump primed if I run a tank empty and miss the signs to switch in time.
It takes a lot of cranking, and that is not easy on the starter.
If you are stuck in the road you do what you have to....
Otherwise you could fill the bowl through the vent tube.

 

Gary, two things, (A) the vapor separator should have the small fitting on the top and (B) the pressure regulator concerns me, the in-tank pumps for these trucks only put out around 5 psi if I remember correctly (AllData shows 5-7 psi but I think that is for a mechanical pump, I seem to remember 3-5 psi) if a later tank and pump were installed, say a 1987-89 model with the low pressure/high pressure pump system the EFI engines used, that low pressure pump is on the order of 15 psi, after 1990 Ford went to the pump modules in each tank and did away with the high pressure pump on the frame, the modules contain the high pressure pump and the return shuttle valves. Considering the filler neck on the front tank, I wonder what other strange things were done.

Jim's truck is a Northern non-A/C model, and didn't get the hot fuel package, properly set up it is a pretty reliable system, just occasionally if the truck sits for extended periods, takes a bit to refill the carb (I used to take the blue fusible link from it's stud on the starter relay and touch it to the hot post until I heard the fuel bowls fill.

 

Jim - Good points. The electric pump, singular, seems to be doing the job for now so why change.

Bill - I won't know what pump I have until I pull it down. And, as said, I'm not ready to do that. But something filled the crankcase with fuel, and that had to be via the needles and seats on an Eddy. So I'm suspecting more than 5 psi from the pump. Besides, the regulator is cheap insurance. There's just the question of which one to use and where to locate it.

Thoughts?

 

Gary, I have a 86 F350 460 C6. Has all the stock fuel and smog equipment. I will send pictures of fuel return system. I had vapor issues until I moved the rubber lines that connect to the plastic lines on the frame. I moved them away from the engine as far as I could and still stay on the frame. I have the Airtex in tank pumps and stock tank transfer valve.

 

Gary, Here are the pictures

 

Thanks, I appreciate it. Pics of the vapor separator and its location, etc will certainly help.

EDIT: Well, you did. Thanks!

 

Well, you said "pics", but there's only one. Was there to be another?

Anyway, apparently the inlet is on the left, the outlet to the carb on the right, and the return on top?

 

Gary, here is where the vapor separator sat on the stock system with the Holley 4180:




In the red circle.

Here is what you are missing as far as vacuum lines go:




That is the complete engine vacuum harness and choke heater wire.

 

Wow! I'm glad to be shed of all of that "stuff". But, I do see why the vapor separator was up there.

Thinking about the return-style regulator, I wonder if there is enough fuel pressure to cause it to return some fuel - thereby cooling things. If not, I'll need to keep the vapor separator.

 

I have a question on the vapor separator.
I am guessing it returns some fuel back to the tank so the fuel never sits in one place and boils.


If so where is the restriction in the return line so the fuel does not follow the easy path?
I know of fuel filters that have 3 ports1inlet, 1 to carb and a small one for return.
The return hose has the restriction in line and is hard to see if not looking for it. Lot of people have thrown it away when "making things better under the hood".


You could use this filter and add a small orifice jet in the small return line just make sure the return port of the filter is at 12:00 or you run into issues.


Just something to think about if you don't have the vapor setup.
Dave ----