79 not starting when hot

[75 C20]

my 79 with a 350 will start up reall easy and good when it sits over night or for awhile but if i drive it for a while and then shut it off then come back a little bit later it wont start. i was thinking it might be my coil but i dont really know for sure. i have yet to find weather it is a fuel deliverly problem or if i am not getting spark- i replaced the ignition control modeul a couple weeks ago also.

[VileZambonie]

You probably have a bad distributor pick up coil

[Lt.Del]

Vile is right!  My 79 did the same thing.  She would run great.  Then after stopping for 10 or 15 minutes and trying to turn it back on, she would turn, and turn and turn w/out firing.  It was getting no spark.  When the distributor cooled for about 15 to 20 minutes w/ the breather off (so it would cool down more) it would start again.  I replaced the simple stuff like coil, rotor, cap, checked the timing, etc...I finally got fed up and threw a different distributor in it (i have like four of them--I collect a few when i go to the salvage yard) and it fixed the problem...still have that distributor in it and she runs like a champ. 

[dumbucket1]

does it have headers? could be heat soak on the starter.

[75 C20]

does it have headers? could be heat soak on the starter.

no the engine is all stock

[Mr79C10]

My 79 has just started that. I have a inline 6 but symptoms are the same, And I have a brand new Optima batt. So  I made up my mind just to buy a new dist. instead of rebuilding it.  Be here this week for next weekend t do list.

[mpellis]

I kind of have the same problem with my 82 K10.  The difference is I can get it started if I hold the gas pedal down while cranking it over. I just had a shop install an Edelbrock carb with electric choke. The truck starts fine when cold. How does this electric choke know when to open or close? 

[VileZambonie]

An electric choke is wired off of your oil pressure switch. When the engine cools down so does the choke coil and closes the choke flap. At the same time it forces the fast idle cam onto it's step and when you start the engine you are supposed to simply depress the throttle 1/2 way (not pump it) and crank the engine until it starts. When you release your foot from the accelerator the choke coil being closed receives current flow through the oil pressure switch circuit. After a short period of time the current flowing through the coil causes it to heat up and expand opening the choke flap and knocking the fast idle cam off it's step. As long as current is flowing through the choke coil it will remain open. When you shut the engine off current flow stops and as the choke coil cools it's closes the choke again.