360 starving for fuel, vapor lock??????

[christineman]

my 360 I built up has 750 edelbrock with cam and heads to match,, it performs better than I ever expected it would.. but,,, one problem..every once in a while, I cant get 10 miles an hour out of it,, its starving for gas.. today it was acting up like that so I pulled the air cleaner, and it barly ran, accelerate it and it all but dies, so I sprayed some ether down the carb while it was idleing and accelerated it and ziped right up there so I know is starving for fuel..so, while it was idleing poorly, I pull the fuel line off the carb, it took maybe .2-3 seconds before anyfuel came out, when it did, it came good,,, put thehose back on the carb and the engine worked fine,, Fuel pump works very fine,, Its electric and fills a pop bottle very fast. so boys,,, whats my problem? vapor lock? i just dont know,, any ideas?

mel

 

[69 Runner]

I run a Carter mechanical on my Duster with no problems. IF you're having vapor lock, your line is way to close to something hot, or your pump isn't working as well as you think.

 

[Redhorse719]

Hey, I got to tell you this and I'm not being a smartazz, never disconnect the fuel line with the engine running. :nono: That could have been an instant fire. :campfire: Check all fuel lines for leaks, on the suction side it won't be an easy check.

 

[Cranky]

You could disconnect the line at the tank and carb and pressure it up and use soap and water spray or some Snoop leak detector....kinda expensive tho. Another way is to pressure it up and use a gauge and see how long it holds. If it's good, I would think it would hold 20 psi at least. If that tests good, you may have to pull the pickup out of the tank and give it a good look. Test the pump too. Put a gauge on it and dead head it, then test it with some fuel flowing but not much and test it hot and cold. Do you have a regulator on it too? I've seen those act up before...

 

[WileERobby]

Check the sock in the tank, also. I also have a Carter mech, I used a heat shield tube (Jegs) over the fuel line from the firewall to the pump, & again from the pump to the carb.

 

[Manifold]

Hmmmmm, haven't heard of an electric pump suffering from vapor lock. It is usually the recommended solution to vapor lock problems.

Is it a rebuildable pump? If you can't find any issues elsewhere, or with any other components in the system, maybe it's time for a rebuild or new pump.

 

[MRHWS]

Accelerator pump in carb maybe?

 

[72 Charger SE]

I would also vote for checking the sock on the pickup in the gas tank. My car plugged up there with rust scale from inside the fuel tank after the car sat for 4 years. It would run fine most of the time, but occasionally it would shut down to barely an idle, with zero fuel pressure showing on the gauge at the carb.

 

[A38Valiant]

I would also vote for checking the sock on the pickup in the gas tank. My car plugged up there with rust scale from inside the fuel tank after the car sat for 4 years. It would run fine most of the time, but occasionally it would shut down to barely an idle, with zero fuel pressure showing on the gauge at the carb.

I once owned a 72 Charger SE 318 that would run all day long at idle, whack the throttle in park and was fine, but drive that thing 3/4 of a mile and it would shut off. Would not restart for 10-15 minutes. Finally traced problem to dirt in the tank. Lotsa big gooey stuff that would slosh around and plug the sock when driven. Let it sit awhile and it would float away from the sock. Repeated attempts to diagnose problem with the car sitting still were futile because the goop would not close the sock when the fuel wasn't sloshing. No idea WTF this stuff was or how it got in there, but it nearly drove me insane. Probably why I got the car for a hundred bucks.

 

[ChgrSteve67]

also check the mech pump rod that runs against the cam.

They will wear down over time and cause the pump to not pump enought gas to keep the carb full.

Most people never think of changing the rod when they change the fuel pump or even when they rebuild the motor.

 

[A38Valiant]

also check the mech pump rod that runs against the cam.

They will wear down over time and cause the pump to not pump enought gas to keep the carb full.

Most people never think of changing the rod when they change the fuel pump or even when they rebuild the motor.

Except the OP said its a 360. No rod. It's an ecentric that bolts on the front of the cam.

 

[1toolguy]

I fought vapor lock too. While removing the fuel pump (also a Carter mechanical) I noticed that the short rubber fuel lines were really soft. I sliced them lengthwise and they were actually sticky inside, probably from her ethanol in the fuel (everything around here it 10% ethanol). I replaced the rubber lines with the teflon lined (blue inner liner) fuel line made for fuel injected engines and the "vapor lock" went away.