Volvo: 1983 240 turbo electrical problem, pump priming, meter gauge

Question
When I activate the turn signal the voltage meter gauge fluctuates from 14v to less than 10v and stalls the car.there does not apperar to be any power at the dash or column and I can not hear the fuel pump priming.
after 15 min or so the car will start normally.

All other accessories seem to function normally although battery voltage was reading less than 12v with all accessories on so I replaced the brush and regulater set. Old one was worn. Voltage is steady at 14v 13.5 with all accessories on.

Turn signal still makes the gauge bounce and stall the car do you think this is a relay or maybe a short circuit?
thanks john

Answer
John,
It sounds more like a short in the lighting system. Try and check your ground wires and if you do have a spare flasher, give it a try,however I can not see why or how that would cause a problem as you are having. Is there a ground wire to the alternator and is it in good shape. That kind of problem will require a bit of searching before you able to find it. Do the idiot lights come on, on the dash with the key in the on position? If not check the red wire (small one) from the alt to the dash...