304 just stops

After some years of working to get my 79 304 running reliably I have a problem I can't figure out. She starts, runs for 15 minutes and then just quits. No missing no restarts it just stops running. 30 minutes later it starts like there was never a problem but will do the same thing 30 minutes later. I have run the fuel lines an they seem ok. Some one said a condenser or capaciter or other electronic problem but I can't find such a thing in the Haynes manual. Anybody got a suggestion......

 

Get the factory manual. It's available in reprint, and will be much more helpful than one of the parts-store manuals.

"Just stopping" is either fuel or spark in 99% of the cases. This is the Ford Duraspark ignition, and module failure is the most likely problem. There's also a pickup coil in the distributor that can fail, but the module is more likely.

JMO - you should carry a spare module anyway, so the best option is just to change it. Keep the old one for a backup for a couple months, then pitch it and get a new spare to carry. I'd go with a Napa or Standard module, though some of the other brands may be ok.

 

What Timgr said. The Duraspark module has a printed circuit board inside that when put into the "box" is folded over. These are notorious for breaking the circuit where they are folded then as they heat up they break contact. Always carry a spare module or convert to GM HEI. When it acts up, check for fuel delivery and spark. I bet you are losing spark... Nickmil

 

I hate the duraspark (start there)..Also...Check to make sure you fuel tank is vented properly...If it is not...it will get to a spot where the fuel pump cannot pull fuel from it anymore due to the vacuum. Not common...but can happen.