Vapor Lock ...???
 

So here’s the deal ...
Every other Flathead I’ve had ran a stock fuel pump ...
I hated the sound of the electric pump on my 48 Stock 59ab...
New Drake pump...
New check valve body to pump hose...
New carb tubing ....
And a NY Charlie rebuilt carb (excellent JOB by the way)
Parade yesterday 85* outside ,,180* on the gauge the whole time ...
Parade over,,, head for home two miles down the road feels like it running out gas ...Whaaa whaaa. Get it started again by hand choking ...A mile later same thing .....Finally ease it home on side roads,so I could keep it moving ...
My question,,,Is this classic Vapor Lock ...does insulating the line between pump and carb help ...??
Hate to say it but I may put the darn Ol electric pump back on and drive without incidents,,trouble free for the 7 years I’ve owed the car ....

Re: Vapor Lock ...???
 

What kinda fuel pump you got? Steel bowl or glass bowl? Could be sucking air from around the lid if it’s steel bowl or from under the glass bowl if you have that type . I’ve found that this fuel we have today will cause the gasket to Deteriorate. I use a gasket made of Teflon on mine.

Re: Vapor Lock ...???
 

A failing ignition coil and.or condenser with cause the symptoms you mention. Today's non alcohol gas resists vapor long, and if your electric pump is doing the job, turning it on should cure any "vapor lock". We mount electric pumps just ahead of the gas tank, and have no complains about noise. If it is loud, check to se if the pump is touching nearby metal, or it is fastened to the frame or other place. I drove my '47 last weekend for 180 miles in 93 degree heat with no problems.

Re: Vapor Lock ...???
 

90% of fuel problems are electrical/ignition.

Re: Vapor Lock ...???
 

Agree.........I say coil.

Re: Vapor Lock ...???
 

don’t understand if it’s electrical what does hand choking to bring it back to life have to do with electrical ?

Re: Vapor Lock ...???
 

Sounds more like vapor lock to me. Hot fuel pump is probably the most likely reason. I suppose it could be a coil or condenser problem, but I would lean towards vapor lock.


Sal

Re: Vapor Lock ...???
 

It's just an old saying. Doesn't necessarily sound like it applies to your problem.

Re: Vapor Lock ...???
 

If you have vapor lock, one way around it is to install a "T" in the line between the fuel pump and the carb. The center outlet from the "T" solder it closed than drill a 1/8" hole in the solder. Run a fuel line back to the neck of the filler tube. This will give you a constant flow of cold fuel.
This is how the Cadillac flatheads came from the factory.

Re: Vapor Lock ...???
 

Back in the day we used to see clothes pins on the gas line, put there because some people believed it would prevent vapor lock, obviously an old wives tale.

Re: Vapor Lock ...???
 

I think the trick of using clothes pins on the fuel line was to pull heat away from the line. Probably didn't work too well.


Sal

Re: Vapor Lock ...???
 

You somehow lost me.. Please 'splain further.

Re: Vapor Lock ...???
 

So the long leg of the T would go back to the tank? If so, then what are you soldering closed? ... and then drilling open again? I'm confused.

Re: Vapor Lock ...???
 

The straight-thru part of the tee remains open, one side to the fuel pump, the other to the carb. The remaining side is closed up and drilled small and goes back to the tank. The idea is to have enough restriction in the tank return line to give pressure to the carburetor, yet flow enough to keep the fuel pump pumping cooler fuel. The restriction works like the restriction on the by-pass oil filter.

Re: Vapor Lock ...???
 

I believe you but how does it not suck air from the return line?

Re: Vapor Lock ...???
 

The return line is on the pressure side of the fuel pump, no suction there. Turbocharged Corvairs also use a fuel return line from the fuel filter to the tank. I always thought it was to reduce the fuel inlet pressure to the Carter YH carburetor with a small float.

Re: Vapor Lock ...???
 

The tee is on the pressure side of the fuel pump so the line is under pressure and the return line has a positive flow back to tank. The return line is separate and has nothing to do with the fuel line supplying the pump.

Re: Vapor Lock ...???
 

Depends on the root cause of your vapor-lock, but a return line will solve a lot of the vapor-lock.

Re: Vapor Lock ...???
 

The supercharged '57 T-Birds and Fords also had a fuel return line that went back to the fuel tank from the fuel filter.


Sal

Re: Vapor Lock ...???
 

Thanks Guys .....
I’m going to put the electric pump back on ....
Plumb it like “Ol Henry,Craig” did ...
Put a center off switch ,,with a momentary spring loaded side for priming ,if need be ,and ON if I experience vapor lock or whatever ....
Like others ,,,my Carter Pump makes so much noise ,,,I’ll never leave it on ...That’s why I wanted it off the car ...
Also going to have the Crab distributor rebuilt and set ....
Sending a coil to Skips .....
I use non-ethanol premium gas (usually) and have no problem ...I can’t help but think this little escapade is a result of the 8 gallons of 87 ethanol I put in .....It wont always be available so I better be ready .....
I like driving this thing ,,and know I’m gunna get home at the end of the day ...