Topic: Re-start Problem 79
in Forum: C3 Electrical
I have the following problem w/ my 79 for quiet some time now, maybe even since I restored it in the early 90's. Car will not start after driving for a long time peroid. I have a 50 to 55 amp alternator on the car, which I know should be a 63 amp. Validated it is putting out amps by two shops. Drove the car for over an hour this past weekend, voltage at the battery was good, digital meter and voltage meter on car was good at all time, even w/ AC and radio/amp on. When the car will not start the starter solenoid does not click at all. You can let the car sit for hours and it will re-start. I have a battery cutoff on battery for non-use of car and I get a battery tender on the battery at all times when not used. The car has never been a daily drive, mostly a show car. Work# 504-391-8439 or joseph.dewey@lanewo.ang.af.mil.
Mike,
Did your test. No drain at all to speak of. Meter and car volt gauge was the same at all times.
Alternator tested by two shops, putting out 50 – 55 Amps
At park, 7RPM…14.17
- At park, 15 RPM 14.22
- At park, AC on 13.8 to 14.0
- Driving, AC off 13.8 to 14.0
- Driving AC on 13.7, left AC on at this point
- Idle AC on 12.7
- 10 mins at park 12.6
- ½ hour 12.3 stopped
- 1 hour 13.1 idle
- Stopped car and re-started 4 times
- Re-started and ran AC w/ Radio/Amp 13.6
- 20 mins 12.46 at idle
- 13.4 running
- 25 mins shut off car 12.62, would not start, no solenoid click? Put jumper box on battery, would not start. Did not reset battery shut off switch.
- Was hooking up my red lead from my noise filter on the back of the alternator, got a spark. Hit the case once, sparked again. Was concerned I may have blown a fuse. Started car. About 10 mins may have passed.
Friend of mind seems to think the Solenoid maybe the problem, he recommended putting a new solenoid on the old starter see if the problem goes away. If problem is still there, replace starter w/ old solenoid and see if problem goes away.
Lifetime MemberModerator
You could test this by hooking a voltmeter to the purple wire on the "S" terminal of the solenoid. The next time it won't start or "click", see if there is 12v at that terminal. If there is, then the solenoid is the problem. If there is NOT 12v at that terminal, then you would need to start looking at a ign switch/wiring problem.
Joel Adams
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My white 79 had a similar problem when I bought it. Drove it home 1000 miles knowing it might not start if I shut it down. The previous owner would disconnect the + cable whenever he stored it. After driving it, he knew it might not start but that it would jump with jumper cables. My first stop for gas on the way home, no start. Got a guy to jump it, still no start. After he left, I tugged on the - cable and it started. Wasn't loose, just apparently not making a good ground. When I got it home, I added a disconnect on the - cable and the first time I went to start it it wouldn't start. Loosened the cable and retightened it TIGHT. No problems since. Seems the previous owner always disconnected the + cable and never though to check the -.
Next time it won't start, try disconnecting the cables at the battery(and the disconnect) and reconnect and see if that helps. If it's been doing it since the 90s it may be something else, but this might be an easy free fix.
