67 911 charging/battery issues, It's why I can't make WCR! Options

[FlacaProductions]

@bdstone914 - you asked - here it is! (posted here because you guys are smart and hands on - the 911 board is less hands on...)

1967 911 coupe. Just completed a “wake-up” after sitting rarely used by the previous owner for a few years. Main issue was gummed up carbs, but all suspension/running/stopping gear restored/replaced generally to OEM/stock specs.

I picked it up April 17 after 2 months of restoration. Ran like clockwork until June 9.

My overall suspicion with this issue - a bad voltage regulator (although I never get an alternator warning light unless it’s at initial start and until the revs have been up for just a bit and then the light goes out as expected/normal) - and/or heat induced high resistance around starter wiring.

Except as noted, headlights/dash lights/accessories all work as expected - even when battery acts dead and won’t turn over the starter.

first incident - Monday, June 9
cold starts fine and drive to anaheim. about an hour - freeway all the way. lights, radio on all the way. no performance issues or dash indicators.

Parked - went to move 5 mins later and it wouldn’t start. slow turnover until battery finally died. portable jump start brought it back and I moved about 50 yards. I thought I’d just jump it again if it failed to start but that wasn’t possible. jump box finally depleted. Clay from Scott’s Independent was about 15 minutes away and brought me a charged battery. Put it in and car fired right away.

to the shop - tested charging system and all seemed well - including swapping of a couple of voltage regulators with no real difference noted to voltage/charge numbers at the battery.

Wrote it off to a battery failure, installed new Interstate and away I went.

After that day, I’ve done multiple small, 10-30 minute “exercise” runs around my area without incident. Including multiple drive/stop/park/start/drive scenarios. Groceries, fuel, errands, etc.

friday June 20 - angeles crest - again - no issues
started fine - ran continuously/aggressively on the freeway and up the hill for 60+ minutes/60 miles. stopped at the top for an hour. Started fine for return. stopped for gas near home - started back up fine.

lights on all the way.
charging phone (rennline iPhone charging mount)
radio on
no issues

saturday June 21 - latest incident
started fine
ran slow up PCH (30 mph for 60 mins) to canyon run at highway speeds, back down 101 to malibu canyon again at highway speeds, stopped for dinner.

on that last leg, I noticed that the the phone didn’t charge and I didn’t have the horn - but did have the horn at beginning of ride. (I always honk coming out of our condo garage as it's somewhat blind to pedestrians)

After dinner, it seemed to crank JUST a bit slower after dinner but started easily. phone charged and had horn.

ran 30mph down PCH (30 mph) just fine for 45 minutes. Lights on. Radio on.

On Sunset, started to stumble (40mph) - especially when going past half throttle. big backfires. finally stumbled and quit.

Side of the road. wouldn’t turn over. lights etc all work. wouldn’t jump start. Left it - came back after an hour - turned over slowly - wouldn’t start. started with jump box. drove home without incident. wouldn’t crank when i got it home.

Sunday june 22 - wouldn’t crank - acts like dead battery. starts with either jump box or after trickle charger applied for a while.

Any input is appreciated - sorry for the long post - just trying to do a stream of consciousness of the details....

[Chris914n6]

Sounds like turning the headlights on is the problem. Don't do that (IMG:style_emoticons/default/biggrin.gif)

But seriously, a battery will last a long time on a running car even if not charging as it's not alot of current draw.

Check battery voltage. Check that it is charging at 13-14v. Check again with headlights etc on.