69 / Alternator light

marktodo · 06-28-2011, 06:32 AM

On my 69 which for the last two years has started every time it was asked is having running problems. When I got it it had a starter button because the ignition when turned all the way right wouldn't kick over the starter. Last year I had Tony the keyman rebuild the ignition and it cured it. For the last month I've had problems where it starts up and then stops in midtrip and won't restart. My mechanic massages it. Cleans up connections etc. and it starts right up but!!!! When ignition is on alternator light is off. When ignition off light is on. We've had two more incidents when it did mid flight stops. Any ideas? On My 356's I've replaced the wiring in the engine compartment. Is their a logical place to do that from on a 911? Thanks in advance for any advice.

Mark Todorovich
PS The tree right behind the car in this picture fell over and pulled out of the ground pulling up about 20 sq ft of driveway last night. Luckily it only damaged the garden and didn't fall on the house or the garage.

jluetjen · jluetjen's Garage

Hi Todd;
I'm not sure about the issue with alternator light. What you describe sounds like the normal operation of that indicator.

When you car dies -- does it crank? Or does nothing happen?
1) If it cranks, but doesn't start, I'd suspect the ignition system.
2) If it doesn't do anything, than it sounds like you've got a similar problem to what I've been working through. Hopefully that thread will be helpful for you.

- John

marktodo · 06-29-2011, 07:33 AM

Hi John , It's Mark, not Todd( happens on the registry to I can't figure how it comes out Todd when i look at my signature etc.) Thanks for your response. When it stops it cranks and gets gas. It's definately spark related. we Think that the warning light might be grounding where it shouldn't and causing the problem. YNZ is talking about a blue wire from the regulator. They were very helpful with info, but they don't have a wiring harness for a 69 and said if they did it would cost about $2300. The big problem is they have to use all of the existing plugins because new ones aren't available.
thanks for your input.
Mark

matt demaria · 06-29-2011, 01:39 PM

Key on engine off----alt and oil light on.
Key off----alt and oil light off.
Normally batt voltage goes to ign switch to alt light and then to regulator. When key is on current flows through light to command volt reg to supply current to armature and thus charge system. When charging voltage to regulator increases, the voltage to the regulator side of the alt light increases so that approximately 12 volts are on both sides of the alt light and it goes out.
Sounds like a problem in the switch or voltage regulator with respect to the light.
Non starting might point to switch, since 69 is the first year for the cd and the power to the cd is fed from the switch (term 15).

marktodo · 08:04 AM

I'm still battling this problem. tony the keyman sent me a loaner ignition. It worked just like the one i already had. The alternator tests as working. The warning Light still is on when the ignition is off which runs down the battery when sitting. Now the Optima is dead. i warrantied it . I'm not sure whether it was the symptem or the cause. I guess my next step is reinstalling it and seeing if the light is on when key is off. It's 100 in St. Louis I'm going slow at this.
thanks for your help
Mark