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Alternator Capacitor And Output Charge Q

Started by 8SixS12 · Jul 20, 2010 · 6postsSMF 2010–26

8SixS12Jul 20, 2010, 8:08 pm · #1

The capacitor on the rear of the alternator jumps between the B and E terminals correct?  Is it directional?  The reason I ask is because I replaced an alternator and I could not see where it was when it fell off as I was removing the old unit.  The new one is putting out about 13.5v over the 12.72v the old one put out.  I was expecting voltage to be closer to 14.1v but I guess I have to account for a little corrosion and the expected voltage drop over connectors and crimps etc.  Any insight would be appreciated.

XanoJul 20, 2010, 11:35 pm · #2

13.5v is fine, so long as it doesnt dip lower than that often.

BoostedVGJul 21, 2010, 12:07 am · #3

Are you getting 13.5 volts at the alternator or at the battery?

8SixS12Aug 21, 2010, 5:01 am · #4

@ Battery terminals.  Mostly I keep an eye on it via the guage on my Blitz turbo timer and sometimes it dips down to 12.5-12.7 which is kinda scary.  Thought it may have been the fusible link but .2v drop @ connectors is pretty standard.  Sorry for the late reply.

Jsvob03Aug 29, 2010, 1:47 am · #5
8SixS12@ Battery terminals.  Mostly I keep an eye on it via the guage on my Blitz turbo timer and sometimes it dips down to 12.5-12.7 which is kinda scary.  Thought it may have been the fusible link but .2v drop @ connectors is pretty standard.  Sorry for the late reply.

200mV?! thats an awfule lot per connector. maybe..maybe 20 mV. are we talking at idle its dippig down, or 2000+rpm? alternator peak output is typically rated @ 2000 (give or take) rpm.

a spec i see at work frequently is 150mV drop on a cable is max. granted, its not nissan specific, but a car is a car.
ProlowtoneNov 2, 2010, 8:03 am · #6

Try testing right off of the alternator leads to see if its charging right. My friend just bought a brand new one and found out that the voltage regulator in it was shot, Picked up the regulator for 30 dollars and soldered it in and it worked perfectly