new alternator ??? [Archive] - xjtalk

96xj

08-28-2009, 04:50 PM

so on my b-day i put in the new alternator my wife got me from pepboys :headbag: its rebuilt with a life time warranty ,:thumbsup:
my battery reads 12.5 with truck off , and 13.1- 13.3 with it running and no a/c.
now with it running and a/c on its reading 12.4-12.5 is that good :confused:
i thought it should be at 13.0-13.5 em i correct ?

Mudderoy

08-28-2009, 09:53 PM

so on my b-day i put in the new alternator my wife got me from pepboys :headbag: its rebuilt with a life time warranty ,:thumbsup:
my battery reads 12.5 with truck off , and 13.1- 13.3 with it running and no a/c.
now with it running and a/c on its reading 12.4-12.5 is that good :confused:
i thought it should be at 13.0-13.5 em i correct ?

Reading where? On your dash, or on a multi-meter? 13.8 is what I remember is the norm.

2000XJ

08-28-2009, 11:13 PM

Are you sure that you tightened the serpentine belt to the proper specs? The belts have to be pretty tight, and if they're not your voltage will drop when you engage the AC.

jimwww

08-29-2009, 10:24 AM

Mine runs at 14.0 - and that is measured with a voltmeter off the two battery posts. This is with the engine on. Mine is stock alternator.

96xj

08-29-2009, 10:41 AM

ya thats with a multi-meter ,so the alternator is no good ?

Mudderoy

08-29-2009, 11:26 AM

ya thats with a multi-meter ,so the alternator is no good ?

Are you sure the belt is tight?

You can always drive over to Wal-Mart, etc... and have them put their analyzer on it.

96xj

08-30-2009, 12:47 PM

whats the specs as far as toque how tight should it be ?

Audio222

08-30-2009, 02:34 PM

14.4 volts is the normal output.

BlueXJ

08-30-2009, 05:47 PM

There is no torque spec for the belt but use a tightness gauge from NAPA.
http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=NBH&PartNumber=KR2&Description=Belt+Tension+Gauge

DETOURS

08-30-2009, 06:43 PM

I'd try another one.
It should push 14 volts, period.....

93gc40

08-30-2009, 06:45 PM

There is no torque spec for the belt but use a tightness gauge from NAPA.
http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=NBH&PartNumber=KR2&Description=Belt+Tension+Gauge

That is the same as the gauge I use, mine is for bandsaw blades. The spec I saw in a manaul, was 150lbs tension.