thanks for the info i might go that route

 

found and replaced fuel relay 460 left me stranded again !i had a small bottle of gasoline with me so i poured some down carb. and 460 ran for aways then shut down again seems like it runs out of gas or vapor locks? i removed return/kickback line and tryed to blow through it had quite abit of resistance but was able to get it cleared put back together started fine felt vapor recovery valve seems to be cool just as ford designed wish me luck because im taking it out to see if this might have been problem

 

I've pulled in high temp situations (see signature) and even with the "hot fuel option" and insulation added to the fuel lines under the hood (a recall that was made to address this very problem) I've vapor locked. Not much to do but lift the hood and cool the carb. I have heard of people using ice applied to the line.

The tanks pick up so much heat from the exhaust that I've literally had the front tank BOILING on more than one occassion. Just to give you an idea of how hot that 2 1/2 pipe and muffler are, I have a ~16" long 4" chrome tip behind the rear wheels that has all the shades of electric blue starting where it's welded to the pipe and fully halfway back. Add already hot fuel to the underhood furnace and it's only a "short putt" to problems. Throw in the added ethanol now mandatory in most states and vapor lock is often the result.

I'm now in the habit of running the front tank down first. If I do the rear first I may just get vapor from the front when I switch over ... even though it is full. I'm thinking about adding more fuel line insulation and wrapping the exhaust pipe and muffler ($$$$$$$) if I have to do any more high temp, high altitude pulling. We've actually eliminated our July 4th trips to CO because of this and started going earlier in the year.

Re: electric fuel pumps
I had to install a NAPA replacement on a Colorado trip a few years ago. It didn't have enough flow to keep up with demand on the hard pulls. Until I replaced it with one of the last new OE pumps in captivity I would have to switch tanks away from the NAPA pump to get on the OE one in the rear tank during hard pulls and acceleration. Good thing I saved all the receipts and packaging because the local NAPA got it back along with a few unkind words about the quality.

I now carry a spare OE pump (purchased from a dealer in MO.) but if I had to find an aftermarket I do believe Holly makes one that will "bolt on" the Ford bracketing in the tank. I think I learned the hard way not to run the tanks empty. I found out later that lack of cooling (low/no fuel in the tank) can cause the pump to heat up and die young,

Re: relays
I carry two spares behind the seat with the fuel pump. On our last trip back from CO I ran the last 100 miles home with the jumper wire (battery to cranking wire solenoid post) that I use to prime the system after it's been sitting too long connected. It bypassed a failed relay. The relays are located in the area between the brake booster and the fender ... sort of under the hinge. Pain in the butt location so I relocated mine.

Back when these trucks were current and common these relays were also a "hot item" in the Ford Parts departments. (Pun intended) I know some were replaced with a Bosch relay that performed more reliabily.

Good luck with it.

 

Just a thought! Check the feed wire on the relay receptical. Have seen these connectors get corroded of dirty and cause relay to get hot. Also mechanical pump is a good way to go. Have one on my 74 Ranchero 460/514 and it does the job just fine. Feeds the 850cfm carb at ful throttle all the way thru 12 sec quarters. Love those bbf's
Norm

 

moral of story when you have a ford learn to carry lots of spare parts! the 460 left me stranded once again. dont think its a relay or pump i can pour a little gas down carb. and it will start if i do this a few times it seems to cool dowm and go? the last thing i have tried is to drill out the vapor recovery valve to .0062 which is 1/16" i will keep you updated if i get back home

 

Just throwing this out .....

Talked to a guy friday night at an informal car show type gathering and he made reference to a problem with check valves in the fuel system on his truck. I've had no problem with a check valve that I'm aware of ... I don't even know of any check valves in the Ford truck fuel system, and for all I know he had no idea what he was talking about ..... but he was stating that he had a bad check valve and he had to start his truck with a shot of gas down the carb all the time because the fuel would "drain back" in the system.

OK, there it is. Is this a possible cause and maybe an answer to this problem ? ,,,, stickey check valves

Anyone with check valve experience ?????

50f1wrench is right about corrosion. Been there, done that.

 

No check valves that I know of in these systems unless there possibly is one internal to the pump itself.
There are four main reasons for fuel getting out of the bowls on the 4180 Holley carburetors.
1. Blown power valve diaphram.
2. Wrong power valve gasket. The 2-Stage power valve uses a gasket with three prongs pointing inward; the old 1-stage power valve circular gaskets won't seal.
3. Bad gasket between primary metering block and main body. There are some "kits" that have thinner than stock gaskets that don't seal well.
4. A leaking float bowl gasket should be obvious due to fuel on the intake manifold.
If the float bowl doesn't leak, there should be enough fuel in it to start/run the engine and have time for the pump to replenish the fuel in the line. The fuel can't be siphoned from the float bowl because as soon as the float inlet needle valve opens any siphoning action would stop and only air would flow back toward the tank.

 

Yes there is one in the pump itself thats The problem I was having when I first got Barney if it sat for a day I would have to crank the crap out of it before my mechanical pump would pick it up,once I changed the tank pump and sender everything was good and never had a problem again.

Does anybody know at what section of fuel line the vapor lock will happen because with the mecanical pump and the fuel line feeding a holley 750 Barney has never had a problem and was thinking it might be the way the fuel line was run.

 

Hot wire the pump with a switch, and you may find your problems go away. If so, the oil pressure switch may be going bad, or if the engine is worn, the oil pressure may be dropping at idle, de-activating the relay.

 

The jumper that Dave is talking about is the one I use to prime my system. On the starter solenoid mounted on the passenger side of the fender has two large and two small terminals. Large= battery in & battery out, small= in from starter position on ignition switch & out to fuel pump. IIRC the rear one is the one we're interested in.


Jumper that and the fuel pump will run until you un-jumper it.

 

The only vapor locks I've had experience with all occoured on the suction side of mechanical pumps. Never had a problem with vapor lock on a vehicle with an electric pump in the tank although I guess it's possible.

 

Where was your relay & what does it look like?

 

I was unaware that the carbed 460's had electric fule pumps(except 87). My 80 F350 i put a 429 in and never had is shut down or vapor lock

 

That posting was made just over a year ago, and that user hasn't been back here since.
Start your own thread.

 

Brad, Ford had a "hot fuel handling package" on the 460 and some 351HD engines. Among other things, fuel pumps can be a royal PITA to find, most places list the low pressure for the EFI system. The carbureted pumps are low pressure, but fairly high volume. They may be centrifugal pumps instead of gear type.