Engine Stalls after aprox. 2 minutes

[BennoVergeer]

Hello,

I own a 911 SC from 1980 and have a problem with the engine. The weather is now fine about 26 deg C and i wanted to drive my car. What happens is that the car will start fine, idle fine every ting is fine and then after about 2 minutes the car stalls. When i then try to start it a lot of electrical stuff does not work ( radio, blower, dash, engine, etc). The generator light does not go on and no high pitch from the CD box. When i now wait for about 2-3 minutes and try to start the car again it starts fine. But after 2 minutes it again stalls. This goes on and on.

I never had a problem before, can any one tell me what could be wrong ??

Kind regards Benno Vergeer
Netherlands.

[boyt911sc]

Benno,

It could be caused by several things but for starter, check the following:

1). Check fuse #18. Do you have power to interior lights, glove box, clock, etc.
2). Is the frequency valve vibrating during the short idle period?
3). Check the fuel pressures ( control and system).
4). Do you get ignition sparks when the engine fails to start?
5). Check your WUR and source of vacuum leaks.

Good luck and keep us posted.

Tony

[Targalid]

When you say that when you attempt to start it that electrical systems do not work: ( radio, blower, dash, engine, etc). Is this only when turning the key to the start position or during the "dead period" before it will restart? If the latter, then you can check your fuse panel during the "dead period" and see if the electric fault can be discovered there. If the former, the fault must be in the starter circuit itself drawing power from the rest of the car. This could be at the starter switch which automatically cuts out other electric circuits while the key is in the start position.

[boyt911sc]

Originally Posted by BennoVergeer

Hello,

I own a 911 SC from 1980 and have a problem with the engine. The weather is now fine about 26 deg C and i wanted to drive my car. What happens is that the car will start fine, idle fine every ting is fine and then after about 2 minutes the car stalls. When i then try to start it a lot of electrical stuff does not work ( radio, blower, dash, engine, etc). The generator light does not go on and no high pitch from the CD box. When i now wait for about 2-3 minutes and try to start the car again it starts fine. But after 2 minutes it again stalls. This goes on and on.

I never had a problem before, can any one tell me what could be wrong ??

Kind regards Benno Vergeer
Netherlands.

Benno,

What type of ignition system do you have on your car? I have encountered similar symptoms in an SC lately and found out the problem was caused by the over-heating CDI unit.

Tony

[Grady Clay]

Benno,
First, welcome to Pelican
You will find a lot of help here.

targalid has a good question.

Tony points you in the right direction.

Your next step is with a ‘test light’ to see where you do not have 12 V power when and where you should.
Test both when the car is operating properly and when it is not.
The difference will give you clues where to look farther.

The systems not functioning indicate something in the ignition switch and back to the battery.
As a simple possibility, clean and tighten the connections at the battery.
The red wires at the battery B+ terminal must be clean and tight.

Again, WELCOME.
Please post some pictures of your SC.

Best,
Grady

[BennoVergeer]

Hello everyone,

Thanks for your replies, i have been working on the car and when i measured the battery i came to the conclusion that my car battery alone (disconnected from the car) gives out 19+ VDC. I think i have been overcharging the battery due to a faulty voltage regulator. When i put the battery back into the car the voltage goes to 22+ VDC.

I have now taken out the battery and discharged it first to next start up a normal charge on the battery. When this is done i will put it back into the car and then see if with the car at idle the voltage is between 13,8 and 14,3. Then when i give it some gas will look to see if the voltage raises above 14,4 VDC. If so my voltage regulator is broken.

Best regards Benno.

[BennoVergeer]

Almost forgot, my ignition system:

I have a Paris Rhone 75 AMP alternator with external voltage regulator and a Bosch CD-box and Bosch coil.

I do actually not know for shore if there is a internal voltage regulator on my alternator. A mechanic i go to installed the external one because according to him there was no voltage regulator installed. The plug was there between the rear window heater relays and the CD-Box, but no regulator.

I also i trying to figure out which voltage regulator i need to order if mine is broken

[Joe Bob]

Replacing the VR is easy if it is external. Finding one is another problem. Most have replaced the alternator with an internal VR.

But you are going down the right path. Hopefully the battery wasn't cooked. Is your meter reliable? Not a good time to use a cheap meter.

[BennoVergeer]

This is a picture of my alternator. I think there is no regulator on the back, therefore there is a regulator between my CD-box and rear window heating relays.

Am i correct in my conclusion that there is no voltage regulator on the back of my alternator?

Benno.