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Discussion Starter · #1 ·
I ve got a 68 mustang with a one wire Powermaster 140 A alternator (i bought it at the beginning of the year) and an Odyssey PC 1400 battery (as new as alternator)



-Battery float voltage is 12.6v
-At idle with lights off, Voltage is 12.6 and slowly climb to 14.7V. Power consumption is about 4A, Power thru charging cable is 8A.
So everything is ok. When engine rev up, voltage drop to 14.4V...


-At idle with parklights on, Voltage is about 14.2V


-At idle with Hi-beam on, Voltage is 12.4V and slowly dropping!. Power consumption is about 20A, Power thru charging cable is 8A (again) so battery is not charging.
Same with revving up the engine.



How could you explain that charging power is the same (8A) with different loads ??
 

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loose belt or dirty connections / alternator ... internal reg
connections ,check by voltage drop , includes the alt. ground

then it could be test equipment fault
 

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Is there a sense wire on the Powermaster? Usually 1-wire alternators will connect the sense wire right to the alternator's output terminal. At that location it can't determine the actual voltage in the rest of the system after the voltage drop through the cables. If you have it, the sense wire should be lengthened and connected to the battery (+) cable, either at the starter solenoid or the battery. Made a big difference in the way mine works.
 

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Discussion Starter · #8 ·
There is two optional connectors, one for light, one for exciting rotor at starting (without waiting reving).

I will connect it and see if it can help voltage sense...

Thank you ;)
 

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i had this same problem, couldnt figure out why it was doing this. the battery was new as well was the altanator. so after cleaning the connectors didnt work; i changed out the regulator and solenoid first. just cause... and it was fixed. i never found out what was the problem.

i assume the regulator, cause of its age (pretty sure it was original)

good luck
 

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Discussion Starter · #10 ·
Problem solved!



It was a [email protected]!.. slipery old belt! But it was splipping without any noise....
New belt with anti slipery spray => 14.5V at idle with all electricals ON!

Thank for your help.
 
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