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alternator output 19 volts?

16 April 2002
Haiku Hawaii
Aloha....my battery went dead today and I bought a new one. We then checked the alternator and it was putting out 18-19 volts. We then checked the new battery and it was only getting 11.5-11.9 volts. What's up with that? Alternator not charging the battery? Need a new one?
Any info will be appreciated........
Mahalo from Maui Boy
how did you "check" the alternator? the system voltage while the car is running should be aprox 14.4 volts, if it is not the battery is discharging, when loaded with a large resistor (as found in most starting/charging system testers) the alternator should put out min of 60 amps at aprox 12.5 volts min.
check fuses 9,18 both 20amp in the under hood fuse box as well as fuse 2,15 amp in the under dash box ....If your voltage at the battery while the car is running is 18-19 volts yout voltage regulater is toast and you need a rebuilt alt or have your rebuilt..good luck ..JZ
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We put a volt meter directly on the alternator and it read 18-19 volts with engine running. We then tested the battery while slightly revving the engine and it read just under 12 volts. The car died as I was driving it home after jump starting it when it would barely start. The voltage gauge kept dropping until the car just stopped. I bought a new battery, put it in, started the car and drove it to my friend;s garage where he then checked the alternator and battery.....how's that for a story. As a side note after the car died, flames were coming out of my exaust pipes on the drivers side for about a minute before they went out. I figure it was fuel vapor heated up by the exaust. What a day.............Maui Boy
check your voltage regulartor.

You can take apart your alternator and replace just that part. Im thinking it will be cheaper then getting a new alternator. It is pretty easy to do. When VR is not working right, your voltage goes really high or low.

Also if your alternator is really oily, most of the time it just needs a good cleaning to allow all the conponents to cool off properly during driving.