440 Issues: Need help this week!
 

This is my first post. I am seeking some advice. I have a 1973 Jensen Interceptor that came with a 440. Car is mostly original with 50k miles but we updated Edelbrock Intake Manifold and 750 CFM carb with an open washable air filter along with electronic fuel pump.

Car was sitting 15+ years and we are working out the bad gas. Zero smoke when it runs.

The car will start with a little pump of the gas when cold but it has left me stranded a few times if I turn it off and try to start again (getting gas, going to store, ect).

What would cause this thing not to fire right back up?

Thanks

j -

Sounds like vapor lock or a variant. That means once the engine bay gets hot and the engine is shut off, the pressure drop + heat causes the fuel to "vaporize" in the line giving you a no-fuel condition. Also possible that fuel can boil (vaporize) in the carb's fuel bowls giving the same effect.

Quick check would be when the engine dies, work the carb manually and see if there's any fuel squirting into the venturies.

Checking/rerouting the fuel line and checking and/upgrading the fuel pump pressure may help.

Archer

I tend to agree. Todays' alcoholized gas seems to boil worse than in the past. Best things I did before finally going to an aftermarket EFI were

Ditching mechanical pump, went to rear mount electric pump

Installed fuel return system. If you use Wix (or equivalent) 33040 (5/16) or 33041 (3/8) fuel filter, these have a built in 1/4" return orifice port, which you return to the tank.

And, a carb insulator gasket.

You might consider yanking the intake off and plugging the intake crossover ports.

So the other concern is my buddy adjusted the timing without marking the timing points so it was hard to get a solid read. The car was running pretty well prior to that.

j -

Some times you just have to go old school. You can time the engine by sound/tach/vacuum (most guys used their ears...)

With old stock engines, wear and tear can change factory specs and if the engine has been modified, the factory specs can be meaningless (almost).

Archer