Over Charging

Reply Subscribe

Thread Tools

Search this Thread

Jan 5, 2001 | 06:50 PM

spectrum

Thread Starter

New User

Joined: Jan 2001

Posts: 14

Likes: 0

Over Charging

May 20, 2002 | 04:57 PM

rayban33

New User

Joined: May 2002

Posts: 16

Likes: 0

From: East Coast

Over Charging

Hi, I have a 1992 F150 5.0 I am having a problem where at anything above an idle the voltage surges up to 18 volts. The truck has a new alternator and I replaced the battery today. The new battery has not helped. I can kick the voltage down by putting on the lights or heater fan. Any ideas guys, before I pay someone to look at this

.

Thanks, Rayban

May 20, 2002 | 05:26 PM

mantta

Posting Guru

Joined: Feb 2001

Posts: 1,728

Likes: 0

From: Keweenaw Bay, MI

Over Charging

Was it overcharging before you changed the alternator and battery? Also, I question the reliability of the dash volt meters, did you check the voltage with a digital voltmeter? The alternator has an internal regulator so, that is where I would suspect the problem. If your voltage is in fact 18 volts you should not drive it because it will boil the electrolyte in the battery and produce hydrogen gas like mad and you will be burning out bulbs and accessories.

May 20, 2002 | 06:07 PM

rayban33

New User

Joined: May 2002

Posts: 16

Likes: 0

From: East Coast

Over Charging

Hi, I did not have an overcharging problem until I replaced the alternator. I have read about connector problems with this year. Maybe the voltage sensing wire going to the Alt.? Bad Voltage regulator on my new Alt?

Thanks, Rayban

May 20, 2002 | 06:24 PM

mantta

Posting Guru

Joined: Feb 2001

Posts: 1,728

Likes: 0

From: Keweenaw Bay, MI

Over Charging

I have an 88 and there was a connector problem on these trucks. I so not know how many years this covered but I got a new set of connectors from Asvance Auto when I replaced mine. The old ones were a little fried. You might check that out.

May 20, 2002 | 07:11 PM

restorit

Laughing Gas

Joined: Jul 2001

Posts: 1,019

Likes: 3

From: Bismarck, ND

Over Charging

I had the same problem with my '85. As it turns out, a diode in my alternator died and killed the voltage regulator. It's very possible you've got a bum alternator, especially if it's rebuilt or remanufactured by someone other than Ford.