FJowners.com

General Category => Maintenance => Topic started by: winddancer on March 14, 2013, 01:01:51 PM

Title: Alternator
Post by: winddancer on March 14, 2013, 01:01:51 PM
I was checking my alternator this last weekend and at 3000 rpm it is reading 15.9v at the battery is this to much and do i need to to do the regulator upgrade? My worry is i have the new lithium battery and i don't want to fry it.
Title: Re: Alternator
Post by: Mark Olson on March 14, 2013, 01:13:26 PM
check all your grounds and connectors first . then do it.
Title: Re: Alternator
Post by: winddancer on March 14, 2013, 01:23:18 PM
if i had a bad ground it would read high at the battery?
Title: Re: Alternator
Post by: Mark Olson on March 14, 2013, 01:53:22 PM
yeah , it don't know how many volts to kick out.
Title: Re: Alternator
Post by: fj1289 on March 14, 2013, 04:52:41 PM
Here's something from Hippy Cain I copied - fairly recent post so you can probably search for the original thread.

"Another thing you can do to extend battery life is to check the voltage at the alternator. Over charging a battery will harn it quickly. The smaller red wire that goes to the alternator supplies the field voltage. If this voltage reads low (it will because it passes through the main switch, and several connections) you will need to clean the switch contacts and connectors. The other fix is to use a relay to supply full battery voltage to the alternator and use the original circut to activate the relay.  My 89 was overcharging it's battery all the time because the reg/rec was always seeing a false low voltage. I have installed a nice Bosh 30 amp relay, a 15 amp blade fuse and some 10 gauge wire and it now works fine."

Title: Re: Alternator
Post by: winddancer on March 14, 2013, 05:24:24 PM
thanks i will check it out this weekend
Title: Re: Alternator
Post by: Mark Olson on March 15, 2013, 01:22:34 PM
Is somebody poking pins in my voodoo doll ? cause now I have a voltage problem. geez  :dash1:
Title: Re: Alternator
Post by: winddancer on March 15, 2013, 11:31:45 PM
Quote from: Mark Olson on March 15, 2013, 01:22:34 PM
Is somebody poking pins in my voodoo doll ? cause now I have a voltage problem. geez  :dash1:

Not my fault I swear  :wacko3:
Title: Re: Alternator
Post by: winddancer on March 16, 2013, 09:43:45 PM
Found the connector was melted together so I fixed that and will retest tomorrow