Two problems: A/C and starting

[A1Avette79]

I have a '79, L48. I have done a lot of work to it in the past 2 years. The Carb was rebuilt, new Ign. Coil (Accel HEI), new spark plugs/wires, new Starter (Powermaster 9200) all done in July 09. This year in May I replaced the Alternator and battery (Optima Red Top), and put in new spark plugs.
In the past several months the car has been getting hard to start about half of the time. There doesn't seem to be a pattern. It can be first thing in the morning when the engine is cold (I live in Miami) or later in the day when running errands and the engine is warm. The gas tank can be low or full. The car will try to start but not turn over. After a few pumps of the gas pedal and some cranking the car stumbles to a start. After starting it seems to run normally - no missing or hesitation. ????
Thats the first problem. The second one is the A/C. It was working fine. Came out of a store and started the car and the compressor wouldn't kick in. Freon is full - just had it topped off last week. It was pumping out nice cold air on the way to the store. ????
Any ideas on where to start on either problem?

 

[Checklst]

I have found most times its just a dirty wire connector somewhere in the system. Start with the wire that kicks in the compressor/clutch and work you way back the switch. I use a vary small flat file and electronic spray cleaner to clean all the wire connectors........even then it still hard to get the little buggers to work.......I still have a problem with high motor blower I loose the high all the time I have cleaned the connector several times and when it quits, I just have to push and move the connector and the blower starts working again....I've cleaned it several times and have tried to bend the blades to make a tighter fit and it still fails every few weeks.

Good luck this old wiring is just a pain.

 

[6880 Mike]

A: Ignition switch. Might be time for a new one.

B: AC circuit breaker/fuse

 

[tracksnblades1]

Have you checked your Q-Jet for bowl leakage? The lead plugs that are notorious for leaking. Try cranking the car at WOT position (to hold the choke unloader on) instead of pumping. Don't try WOT starting unless you engine is in tune and return to idle as soon as it hits.
Have someone look at the exhaust to check for black smoke(rich) or lean starts. Pumping can indicate inoperative or improperly adjusted choke circuit.

 

[LVMYVT76]

on the a/c, check for 12 volts at compressor plug, no 12 volts, start checking back on the circuit. I bet that it's thehigh pressure switch connection ic loose, then 12 volts won't go the compressor to pull in clutch.

 

[TimAT]

Just another thought- just aft of the distributor and a little to the right coming out of the main harness is a 6-way connector- starter extension harness. All the power to the car runs thru that connector. If it's corroded, dirty, burned or nasty it could drop you at random.