Over Charging 87 Carerra
Thread Starter
Intermediate
Joined: Oct 2010
Posts: 46
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From: Buckeye Lake, Ohio
Over Charging 87 Carerra
My low beam headlights appeared to be surging brighter which was accompanied with a seat belt warning light which has happened several times recently. A search of the threads found similar references all pointing to an over charging condition. A check of voltage with the car running indicated normal readings.
I decided to go further and brought the car to have the battery checked as a start. The battery was about 25% low in cranking capacity and during the test the a system was charging at 16+ volts. I replaced the battery and installed a plug in volt meter to monitor.
I checked the car cold for voltage which was again normal with the car running. I took the car for a 20 min drive. It was reading 14.4V during the drive with the exception of a spike to 17+V while starting from a stop. Upon returning I shut the car off and let it sit for 5-10 min. Upon restart the voltage went to 16+V and held steady. It would not be unusual to have a heat related problem with the alternator/regulator.
Give that it appears to be the original alternator/regulator I am planning to replace it based on this condition. Does anyone have any alternative thoughts on this problem.
Thanks,
Bill
I decided to go further and brought the car to have the battery checked as a start. The battery was about 25% low in cranking capacity and during the test the a system was charging at 16+ volts. I replaced the battery and installed a plug in volt meter to monitor.
I checked the car cold for voltage which was again normal with the car running. I took the car for a 20 min drive. It was reading 14.4V during the drive with the exception of a spike to 17+V while starting from a stop. Upon returning I shut the car off and let it sit for 5-10 min. Upon restart the voltage went to 16+V and held steady. It would not be unusual to have a heat related problem with the alternator/regulator.
Give that it appears to be the original alternator/regulator I am planning to replace it based on this condition. Does anyone have any alternative thoughts on this problem.
Thanks,
Bill
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From: Bend, OR
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From: Calgary, Alberta
Thats me, replaced the VR went through all that trouble just to go and do it again to replace the alternator anyway. Skip the first step and save the trouble of doing it twice. Easy 1/2 day by yourself or a whole day with help....haha
Rod,
Rod,
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Thread Starter
Intermediate
Joined: Oct 2010
Posts: 46
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From: Buckeye Lake, Ohio
Apparently there is no way to know which product is in the car. It appears that it is likely the Paris Rhone. Was Bosch an OE supplier or an aftermarket replacement? Do the remanufactured units have a poor history?
Instructor
Joined: Aug 2010
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Joined: Jul 2002
Posts: 16,557
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From: Bend, OR
No, it doesn't, but I also view my time as valuable. Also, every time one takes the alt out, I feel they run the risk of damaging the fan or the shroud-both somewhat delicate after so many years, and very expensive.
More of a strategic move in my opinion.
More of a strategic move in my opinion.
Drifting
Joined: Sep 2001
Posts: 2,467
Likes: 16
From: redmond wa
After such a long period of time in a vehiclar engine compartment environment solid-state devices(***) have only one reason, mostly, for failing.
Overstress/HEAT.
*** Bridge diode rectifiers(6), VR switching transistor.
I would say that if you discover a need to replace slip ring brushes due to wear then replace the alternator assembly in whole.
Overstress/HEAT.
*** Bridge diode rectifiers(6), VR switching transistor.
I would say that if you discover a need to replace slip ring brushes due to wear then replace the alternator assembly in whole.