Good Morning:
I wanted to get some verfication on a diagnosis I made on my charging system this week. Issue was that I accidently had a wrench fall across my battery terminals (I know...I know....I have a rubber boot on the + terminal but I was taking the battery cables off when it happened) and wasted my new/old optima redtop. I bought a new red top and after running the car for 2 mins the battery started to hiss. I called optima and they said the battery was probably being over-charged but to get it load tested just in case. I had a load test performed and it passed. I then decided to verify if the voltage regulator was the issue
I devised the following test with Mike Dailey:
1.) Measure battery voltage without car running
2.) Start car
3.) Put volt meter across battery while car is running
4.) Observe for a steady output ~14-14.4 Volts with no accessories on. With accessories ~13 volts. AMP's should subside if battery is charged.
5.) Shut off car
6.) Measure battery voltage. Looking for ~12.8 volts.
I conducted the test this morning with the following results:
- Pre-test battery voltage ~12.4 (no engine running)
- Engine Running Voltage 18.6 (Runtime was ~ 60-90 seconds)
- AMP Guage: Pegged to the right!
- Post test battery voltage 13.9 (no engine running)
- Battery making slight hissing noise out of top ports
Questions:
1.) Is my voltage regulator fried?
2.) Is the stock alternator an internal regulator design?
3.) Is the correct replacement alternator for a 1974 Pantera the same as a 1971 Mustang?
4.) Any other observations you would like to share with me?
Thank you in advance for your input and insights.
Khan Smith
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