Hard start sometimes?
 

I put a 1406 on my truck seveal months ago and it runs great with one exception. Cold start it does fine and sometimes it starts great after I have driven it for a while. Other times when I shut it off I detect a gas smell and if I just kill it for a second, like to run into a store, and try to restart it will crank forever before it runs. Other times I get no gas smell and it busts right off. I do have an electric inline fuel pump on this truck and was wondering if it might still be pumping fuel to the carb and flooding it. Any other ideas?

Sounds like your problem may be related to the electric fuel pump. Do you know how much pressure it's putting out? A carb only needs 4 or 5 psi. If the pump is overpowering the needle and seat, your engine is getting flooded. Not a good thing for sure. Buy a regulator and pressure gauge. Don't guess with things like this.

Mike, I have an inline regulator set to 4 psi but I suppose it could be faulty? The PO swapped in a '90 TBI pickup motor but used a carb instead of the electronics. I'm considering changing back to a mechanical pump just be safe.

If it is getting flooded when it cranks forever and won't start....try holding the pedal to the floor while cranking...don't pump it...just hold it to the floor....this worked well on the cars I've had that got flooded.