I'm new to the forums and I have an 85 F 350 ford truck with the 460 in it. It has dual tanks and an electric fuel pump in each tank and a factory holley style carb. I have replaced both fuel pumps and the tank valve works fine, I can run it on the front or rear tank with no problem. I am wanting to toss the cast iron intake and do a new carburetor. The engine is stock so i'm guessing that a good 600/625 cfm should be fine on here. There is a little splitter or something just before the carburetor and i'm guessing it's a regulator but i'm not sure. Not sure if this part is working good or not but haven't put a pressure gauge on it to see yet but it does run pretty good. I don't drive it daily and if it sits for more than a week it is a pain to get started and I usually wind up pouring a little gas down the carb to get it to run.

Once it starts up it runs good and start's up good until I let it sit for a week or so again. Just want to know if anybody has upgraded their fuel system using the fuel pumps and the regulator that is already on the truck. The EGR valve is blocked off and the smog pumps are history too.

Also the inertia button shorted out a couple years back and burnt up the fuse link for the fuel pumps so I wound up bypassing the inertia switch. Also I bypassed the oil pressure cut out too. The engine has 140,000 miles on it and I have always kept the oil changed and the oil pressure on the gauge reads great but I have just done what I had to to keep it running.

It's a good running truck but I would just like to toss the original intake and carb and do an eddy performer and a good 600 carb that isn't the factory one but I want to retain the rest of the fuel system. Thanks Chad

 

The splitter thing is the return system for the pumps. It has a calibrated orifice that lets a portion of the fuel sent to the carb to return to the tanks. This keeps the fuel supply cooler, especially at idle sitting around on a hot day.

On a hot day at idle the engine doesn't use much fuel, so most of the fuel would be sitting in the fuel line waiting to get to the carb, and it would have more of a chance of heating up and causing vapor lock. The splitter/orifice deal lets a portion of the fuel go back to the tanks where the higher volume of cooler fuel is located, keeping the fuel moving in the fuel line, keeping it cooler in the lines.

You can keep this system with the new carb, it just might be a little bit of plumbing involved to hook it to the new carb. If you are going to get a holley, most of those have external site plugs for the fuel level, and external fuel level adjustment screws. You can fine tune the fuel bowl level using the original system once you get it hooked up.

The other stuff you disconnected were there for safety reasons. If you are in a accident and get knocked out, you probably won't turn the ignition key off. If one of the fuel lines happens to get cut, then with the key on the fuel pumps are going to keep running and empty the fuel tank all over the accident scene. More than likely the engine will not be running, so no oil pressure, so that cuts power to the pumps. That along with the inertia/impact switch that kills them if you hit something hard.

 

I agree with Dave - fix the safety issues.

Also, the return system, the "splitter thing" isn't a regulator. I don't know what pressure it gives to the carb, and since there are three different orifaces the factory used there's no way to know. But, I do know that the Edelbrock carbs don't like more than 6 psi. So if you go with an Eddy carb I would replace the return system with a return-style regulator. That's my plan.

 

Something else I am not sure of; Most aftermarket pumps are self regulating, they have a bypass regulator built into the electric pump(or mechanical pump). So you can dead head the pump and it won't hurt it, it just bypasses internally. I don't know if the factory pumps have a bypass if you wanted to get rid of the return system. And then like Gary said, if they do have a bypass we don't know what type of pressure they would develop before the bypass in the pump kicked in.

I am always suspicious also as to why Ford went to so much trouble and expense to put this system on these trucks, really only the 460 equipped trucks. It must solve some sort of problem they had, so I would think carefully about it before I got rid of it. We have had a poster or two on here before that had 460 equipped class C rv's, and had serious vapor lock issues with those, and had to go back to this type of system or go to special means to keep it from vapor locking. I can see a loaded rv pulling a mountain very slowly on a hot day getting into trouble very quickly.

 

And then only some of the 460's. And the orifice varied - for what reason we do not know.

Anyway, I'm not advocating doing away with the "system". Instead, replacing the orifice with a proper regulator so the pump can still circulate gas to keep it cool. Basically, this is the same thing as the Instrument Cluster Voltage Regulator, which was a very crude, and probably cheap, design. Why not replace it with a proper regulator?

 

Had to bypass the inertia switch since something shorted to ground and burnt up the wiring harness. Once I did this the harness quit melting. I can hook the oil pressure switch back up pretty quickly. I bypassed this to see if it would start better after sitting since I don't drive it that often. I was tinkering today and noticed the choke isn't closing at all in this hot weather. I may try to see if I can adjust this so it will work a little better in the hot weather. I think the carb is just kinda out dated and it could use a good upgrade. The original seems a little bit lean to me and I think a good universal replacement would give it a little more zip. I jetted this one up a few years ago from 61's to 64's to get rid if a lean miss it had and it does run out good but on the upper rpm range it seems to lean out pretty quickly. I know the stock cam isn't going to pull 5000 rpms but it still should do a little better than it does I think.

The old truck runs out real good for it's age, I had to pull the heads a couple years back since the passenger side exhaust manifold gasket blew out and it sounded real bad. Tried to pull the manifold and three bolt's broke off so off the the head's it was to get them repaired and a good valve job done on them. There was very little sludge in the valley and the cylinders looked real good.

The fuel system has always worked good but it just seemed strange to me how it is set up. Does anyone know if you can purchase that orfice/splitter if I need to replace it or would it be better to install a fuel regulator with a return if I ever need to?

Got a few iron's in the fire right now but i'm planning on doing a carb and intake swap in the future. I like the quick fuel black series 600 carb. I think that would be a good one to go with since it's very similar to the carb that's on it. Thanks for the replies!!!!

 

I bet I know what is wrong with your carb and why it won't start after it sits for a week or so. I had one that did the same thing, it was because I pulled the emissions hoses off the carb, specifically the bowl vent hose(the large ones coming out of the top of the carb). When you pull these off, the gas in the carb rapidly evaporates, which is why you have to crank it so much.

And one more thing on your system that can cause long cranking. Since you have re-wired some of it, does it still have the hot wire going to the starter solenoid? Ford used the oil pressure system to run the pumps when the engine is running, but when starting there is little to no oil pressure. So they wired a bypass that sends power to the pumps from the starter solenoid so they will fill the carb when cranking. So this might be part of your problem also.

Here's a diagram showing this system and you can see the wiring to the starter solenoid.
In the diagram below, fusible link "T" goes to the starter solenoid terminal "I".

Electric Fuel Pump Control - ???Gary's Garagemahal

 

You may have a point on the vent lines that go into the bowls, mine are both just open. I know the regular holleys don't have this vent line so could I plug these off and it still run ok??

And about the fuse link it is still hooked to the I terminal on the solenoid switch. This is one of the wires that burnt up when the inertia switch shorted out. I know this is working for sure because I replaced the solenoid swith and the new one I purchased was bad and as soon as I hooked up the I terminal wire my fuel pump was running. I had to take that one back and swap it for another one.

I wound up with a borg warner switch that actually worked and I even tried to go to ford and purchase one and it is discontinued.

I did find a post on here about three different fuel vapor separator's, one with a .090 return orfice, one with a .060 return orfice and one with a .040 return orfice. I wonder which one mine has on it and if the .040 would be better and may help some of my lean feeling with this carb. The truck doesn't bog or die out but it just seem's to be holding back slightly. It may just be the way that carb is tho being an emission style carb.

I know lately with this ethanol gas I have had to jet the carb up on my old charger to get it back to normal. Just a few jet sizes you know and I wonder what metering plate is in this carb and if a regular 600 holley has a bigger one that is in this one.

I tend to over think things so you can stop me anytime, lol. Thanks for the replies, I am a pretty good mechanic but I am always up for suggestions......

 

Charger? I have a '69 Bee.

I wouldn't start swapping the orifice trying to fix the lean feeling. You said the EGR is blocked, but that carb was designed for EGR. And the ignition curve was set for EGR. I'd go with an aftermarket carb and see if that fixes the problem before playing with the orifice.

 

460 gets very hot in a van chassis and having the hot fuel handling package is a good thing.

The reason you have to crank on it after its sat for a while is because your fuel bowls are drying out over time. Either because of the way they're vented or the front fuel bowl is leaking...

Next time you go to start it after its sat for a while, jump 12 volts to the "I" terminal on the starter solenoid for about 10 seconds. That should activate the fuel pump and prime the carb. Should start without a lot of cranking that way.

 

In my experience no. When I capped my lines, it made the engine hard to start in hot weather, it seemed to "flood" it some. We had a big debate in a thread on here about it, one guy swore up and down it did not make any difference and had theories to prove it, but several other people had the same experience I had, long cranking to clear a flooded engine with the vents capped.

You can try it with that in mind, and see what you experience with them capped. I am pretty sure though, your dry carb problem will be reduced.

 

Carbs need some place for the vapor to go. If you block the vents the vapor pressure due to hot gas evaporating right after shutting the engine off will raise in the bowl and that will push liquid gas through the passages in the carb and into the intake manifold. And there it will evaporate and escape into the air if given time, or make the engine hard to start if attempted quickly.

I'd rather have the gas still in the bowl and smell that little bit of vapor.

 

Holley unlike MC carbs has the bowl vents in the air flow into the carb.

They make baffles for the Holley vents because in racing (drag mostly) fuel moves to the back of the carb. This is not an issue for the rear bowl but the front will have fuel come up and out the tube and flood the motor.


Sometimes even with the baffles you can have issues so you might be able to add longer tubes but that may not fix the flooding from fuel out the vent tubes.


So you do something like this with rubber hose with a notch cut in the top center to vent the bowls.



For the off road guys they also make off road float/needle assy. to keep the float from bouncing.
I have used all of the above depending on the type of racing I was doing but all did get the rubber hose from each vent tube with a notch in the center top.
Dave ----

 

I have a 68 charger but it has been updated to a 69 model. I never liked the 68 taillights unless it is on a black one(bullitt) and I have always like the general lee so it is hemi orange with a black R/T tailstripe. I just like the 69 taillights better, seem cleaner to me and I like the divider in the grille. One of the first mopars I worked on was a 69 bee F8 green 4 speed with a 383. Super nice old car, I like the 69 and 70 bee's and the road runner's and the 71 road runners are growing on me. Glad to see another mopar guy on here, I have one old mopar, several jeep grand cherokee's which are also mopar's aand one ford truck.

 

I have an old 600 holley carb with electric choke on the shelf, I may purchase a kit for it and see if it will work on there. It came off of a friends 79 F150 and he put an eldebrock carb on it and I got the old holley. I can always swap the intake later if the carb works out ok.