Look what I've got. Hope chinesium alternator
- Thread starter Alberto
- Start date
Got a few theoretical questions.
1. how do you check the alternator? If I feed 12V to the excitation terminal, it should generate a bit of voltage when I spin it, even by hand, right? And I should feel some resistance while turning the rotor?
2. Why use a Lewis pin to line up the meshing gears on the rotor? Why not use a splined tool to turn the inner rotor while pushing the gears in?
1. how do you check the alternator? If I feed 12V to the excitation terminal, it should generate a bit of voltage when I spin it, even by hand, right? And I should feel some resistance while turning the rotor?
2. Why use a Lewis pin to line up the meshing gears on the rotor? Why not use a splined tool to turn the inner rotor while pushing the gears in?
Uncle Phil
Site Supporter
It has been done - someone machined a jig to fit on the alternator shaft to spin it in a drill press to check voltage.
I thought the alternator would come to live a little even if I turn it by hand supplying +12v to voltage regulator terminal. It did't, hmm...
Uncle Phil
Site Supporter
Not for sure, but I think it has to be spinning at a certain amount of RPMs to work - don't know what that amount is.
**EDIT - FWIW From Mr. Google -
Alternators typically need to spin at 1,400 to 2,400 RPM (rotor speed) to begin charging efficiently, though they can produce lower output at idle. Because the alternator spins 2–3 times faster than the crankshaft, this usually corresponds to a low engine idle speed of around 600–800 RPM.