Alternator output test

[Jordi]

What is the proper way to check an alternators output?

I've bought a second hand ford 55amp (think i've found a 70amp tho). Presuming it's the right one and bolts straight in how do i check its output? Voltage and amps?

Your electrical wisdom please.

Thanks
Jordi

[suzukisteve]

Whack a meter on the battery when she's running. Then turn everything on like lights etc. If it's working properly it should read something like 14v goin into the battery I believe

[Darrell]

Both tests with the load off IE: lights.

The most basic test is to test the battery voltage with the engine off (Should read about 12 volts)
Then the test battery voltage with the engine running (should read about 14 volts)

More than 15v and the voltage regulator is knackered.
To test the output amps is not possible with a standard multimeter.
However if you test the battery voltage when running and switch the lights/heater fan etc the battery should still read about 13 volts.


Show's how long it takes me to type Steve's posted in the meantime

[Jordi]

The alt i got looked identical to the 90amp conversion on difflock

http://forum.difflock.com/viewtopic.php ... alternator

But i'll be damned if it's gona bolt straight in.

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The brackets on the alt are too wide for the engine mount, fit spacers was that, well i would've. But it i slide the alt forwards the pulleys don't line up and if i slide it backwards the casing fouls on the engine mount.

Back to the scrap yard!!!

[Darrell]

Bummer

[Tramp]

It will be hard for you to test the actual amp output from your alternator, you would need To measure the volts & the current with a variable electric load, you would start off with no load & then increase this load until the voltage starts to decay, at the point the volts start to drop off you take your ammeter reading at that will be the amp rating for the alternator

[Edweird]

The pulleys on mine are out of line anyway.

[ScottieJ]

I need to sort my alt out! Been driving around with the sidelights and blowers on to keep it at 14v reads between 15 and 15.5 at the moment, think all the water has killed the voltage regulator

[Tramp]

My clio's voltage regulator died & cooked x2 cells in my battery before i got it sorted - d'oh! So don't leave it to long!

[suzukisteve]

I've gotta pull my finger out and see if a can get that 200tdi one in there. It's just non stop rain and cold! Gonna need help with the wiring tho