66' Flooding(?) After 30 Min?

[MDC]

I'm new here - and new to owning a Mustang. My dad's 66 convertible was recently handed down to me after being nicely restored. Everything seems to run great but one thing.

If I drive it for, say, 20-30 minutes and then park it for another 15-30 minutes, when I try to start it up it really struggles to turn over. You have to keep the ignition fully engaged and ride the gas pedal for it to finally turn over.

This doesn't happen when it's been sitting for a while (like over night) - only when it's been recently driven.

Any suggestions on a good starting place to sort it out?

It's a 3-speed 289 v8 convertible. Thanks for any suggestions!

 

[horse sence]

What do you mean when you say turn over ? If it will not turn the motor it may be a bad starter .
if it just turns over and will not start the accelerator pump may be bad or it may be vapor locking .It could also have a weak fuel pump .Next time it does it remove the air cleaner and pump the throttle by hand and see it the accelerator pump is squirting .

 

[7991LXnSHO]

The cables and grounds are suspects in a slow cranking situation when hot condition. If your starter bench tests fine, go on to the big wires.

If it is flooding, the engine will spin fine, but will be hard to get running. That could be a needle seat that leaks the line pressure into the intake manifold or a low buoyancy float. This will usually be a smelly problem, often with black smoke out the tail pipe.