Alternator voltage?

[punisher72]

Hey guys and gals! Just wondering what the voltage at the alternator should be when idiling and revving? I have a 2 wire birdcage type! Also when i start my v8 the starter motor keeps free spinning and making a horrible grinding noise? Its not rubbing on ringgear its just free spinning? Could it just need a bit of a grease up? Thanks for replys.

[dodj]

It's a little higher when revving but I'm usually happy with 13.8-14.4vdc. At idle an unmodified mopar electrical system will discharge somewhat.
Your starter engagement solenoid/plunger or whatever it is called  is probably worn out. It's replaceable, but you could put in a high torque mini starter off a late model Ram  truck 

For a lot of info on the charging cct check out Shadango's thread  16.4v at the battery.

[punisher72]

Thanks dodj. When revving mine reads 13.8? Could it need a rebuild? Batterys in the boot and i do have a little trouble with the battery going flat? I will have to pullout the starter and have it checked! 

[dodj]

Doesn't necessarily mean your alt needs a rebuild. 13.8 is at the low end but I don't think  it's too bad. There is also the regulator, wire condition, connections that affect voltage level. You said your battery is in the boot (you must be from UK or down under ) so you have a long way to go to charge the battery so it needs to be a large gauge wire and in good shape. Is that where you measured the 13.8?

[punisher72]

Yeh MATE  Im from downunder. i dont actually have a wire going back to my battery,i just ran an extra 4.5 mm wire from alternator to starter relay!!!!!! I measured the voltage at the alternator,starter relay and the battery. Would it make a big difference running a wire straight to battery?

[dodj]

Would it make a big difference running a wire straight to battery?

No it wouldn't.
I was talking about the wire that goes from your battery to the start relay, not the wire from the alt. Because your battery is in the trunk I was just saying it needs to be a bigger gauge than the usual 2 foot long wire when the battery is up front.
If you measured 13.8 at all three places you mentioned, your wiring must be in good shape. If you are unhappy with 13.8v, a different/new vr might fix you up. I just checked mine running @ 2000 rpm and read 14.8v at the battery.

[punisher72]

Again dont think it would make a difference but ive got a thick cable say 12mm running from the battery to the starter motor then a smaller wire from starter to the starter relay! Otherwise its all good i guess