alternator light just came on?

[plumb4u2]

Ok guys I have searched but want your opinion before I proceed

Yesterday I came home from work and pulled in the garage and noticed that the battery light was lite (first time this has happened in my year of owning). I reved the engine and it went out then after bout 30 sec of idle came back on.

I searched some threads and did some checks
my belt is tight and no slipping (I replaced belt this winter as maintenence)
today I checked voltage at battery with car at idle 12.4v...had wife rev to 3k and got 13.4v

So from these checks I believe that alternator needs to be replaced?
Battery was made 09/09

[Bob Kontak]

Does the voltage bounce around a little when measured? If so probably the v regulator.

[86 911 Targa]

Originally Posted by plumb4u2

Ok guys I have searched but want your opinion before I proceed

Yesterday I came home from work and pulled in the garage and noticed that the battery light was lite (first time this has happened in my year of owning). I reved the engine and it went out then after bout 30 sec of idle came back on.

I searched some threads and did some checks
my belt is tight and no slipping (I replaced belt this winter as maintenence)
today I checked voltage at battery with car at idle 12.4v...had wife rev to 3k and got 13.4v

So from these checks I believe that alternator needs to be replaced?
Battery was made 09/09

You should have 14.5V @ 3K RPM's.

Things are pointing to the VR, easy to replace.

Get your system checked out.

Someone sent me this.

[plumb4u2]

i did not notice reading bouncing around but i will recheck

if it is the VR would it make sense for me to replace just that or the whole alt.
i believe i saw our host sells vr for 65.00 for that much wouldnt it be better to replace whole unit

i have no history on this alternator

[wwest]

Miles...??

High miles....

Alternator slip ring brushes have worn out.

[Driver_X]

If it's an un-modified '84. Then the VR will be integral to the alt. Change out the whole unit....

[plumb4u2]

yes un-modified '84 only 91k miles

Autozone has a duralast alternator, has any one used this as replacement

165.00 vs almost 300.00 from our host for a bosch

I know the VR is integral to the alt but it can be replaced just dont think its worth the gamble

[Joe Bob]

I prefer to have a local shop rebuild mine....

[plumb4u2]

Hey Joe Bob, or anyone else, what type of shop will rebuild Alt.... meaning what should I look up in the phone book

[Joe Bob]

altenators, starters, automotive/electrical, or ask the local wrench for a referal. Good wrenches don't buy Manny, Moe and Jack crap.

[boyt911sc]

Originally Posted by Joe Bob

I prefer to have a local shop rebuild mine....

Whenever I have problem with either my starters and alternators, I simply pull them out and bring the unit to my local electrical shop. It takes a few minutes for these guys to determine the condition of your unit/s unless you are familiar or have the apparatus to make the tests. My starter is 15 years old after the rebuild and still going strong.

Tony