Alternator issue.

[Sajin]

When starting the car the alternator doesn't start charging until the engine is revved to 2000RPM. I have three alternators and they all do the same thing. One is a 130amp reman ford alt, the other two are new alts from ebay, one is a 160amp & the other is a 200amp. What would be causing the alternator not to kick on until the engine is revved to 2000RPM?

Thanks,
Jeremy

 

[hotcobra03]

Was anything changed on car as to smaller pulley, idler.belt?

 

[Sajin]

As far as I know nothing has been changed. The car just had a new engine put in it. Maybe the shop screwed something up?

 

[big dad]

I don't think this is any unusual condition, the field needs to be excited to start charging. Usually requires the rpms to exceed 1500-2000 momentarily then you're good to go. Start a car without bringing the revs up, if it's idling slow enough see what the alt. volts are at. My guess is they'll be low until you stab the gas.

 

[MalcolmV8]

I don't think this is any unusual condition, the field needs to be excited to start charging. Usually requires the rpms to exceed 1500-2000 momentarily then you're good to go. Start a car without bringing the revs up, if it's idling slow enough see what the alt. volts are at. My guess is they'll be low until you stab the gas.

Can't say I've ever experienced this. My cars alternators are putting out good voltage right as you fire them and they're idling.

 

[START 'N CHARGE]

Make sure you have voltage at the alternator plug harness with the key on,both outside terminals.

 

[Tractionless1]

When starting the car the alternator doesn't start charging until the engine is revved to 2000RPM. I have three alternators and they all do the same thing. One is a 130amp reman ford alt, the other two are new alts from ebay, one is a 160amp & the other is a 200amp. What would be causing the alternator not to kick on until the engine is revved to 2000RPM?

Thanks,
Jeremy

Send the Ebay units back they're worthless. I saw the dyno sheets for them and they make about 40a at idle and don't hit full rating until nearly engine redline. As a comparison my Mechman, rated at 180a, reads 170a at idle.