1987 Corvette Charging Problems
Thread Starter
5th Gear
Joined: Jun 2016
Posts: 5
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1987 Corvette Charging Problems
The car has recently started jumping voltage (week ago) it would stay at 13.5 during start up and warm up, but after the car was at tempature for a short while (10-15 min) it would jump from 13.5 to 13 then 12.8 back to 13.8 then to 12.4 and back to 13. The voltage never got below 12, but I went to start the car this morning and it was completely dead no power even to the accessories. Thank you for your help and time.
Team Owner
Joined: Sep 2003
Posts: 25,385
Likes: 2,737
The car has recently started jumping voltage (week ago) it would stay at 13.5 during start up and warm up, but after the car was at tempature for a short while (10-15 min) it would jump from 13.5 to 13 then 12.8 back to 13.8 then to 12.4 and back to 13. The voltage never got below 12, but I went to start the car this morning and it was completely dead no power even to the accessories. Thank you for your help and time.
I'd consider having the entire electrical checked using maybe a carbon-pile load tester by a quality shop IF you don't have correct meters and understand the diagnostics. You can of course check/clean all of the battery terminals, confirm good grounds and proper connections at the alternator and check maybe condition of belt and tensioner.
An auto parts store check of battery/alternator sometimes certainly leaves something to be desired.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
If an alternator is intermittent the voltmeter will jump between the alternator output voltage and the battery voltage. If the voltage goes below 11.5 volts the red light will come on.
My voltage was jumping up and down as described. I took the alternator apart and cleaned everything and put it back together. It has worked fine ever since (several years).
My voltage was jumping up and down as described. I took the alternator apart and cleaned everything and put it back together. It has worked fine ever since (several years).
