Ok where do I test the ALT output ? Do I put the NEG on the braket and find a wire at the plug that go's in the back of the ALT, or do I put the mutimeter on the battery ??

Also I forgot to mention that ever since I had the ute every time I start it the ALT light comes on untill I give it a little rev.

Regards
amshw

anywheres good, just do it accross the battery terminals, it will all read the same whether its working or not provided the wires are all connected

on a side note

how do you manage to have so many small problems with your datto, its not supposed to be like that, these things are reliable but you keep coming up with one problem after another

just bad luck i guess hey?

Murphy's Law I guess, but more its me I really hate litttle probs . I cant stand "just let it go" everything must work properly, but your right it seems every week there's something else, I hope I will get there soon. But I rather get them fixed now rather in the Fire season which is going to be a big one !!

Regards
amshaw

You could measure the battery voltage before you start the car and then again when the car is running. The voltage should be at least above 12V and normally around 14V, as previously mentioned. My volt meter usually shows between 12.5V to 15.5V.
Measuring before and after kind of gives you a reference.
With my car, it's usually the alternator that goes bad. More specifically, the brushes wear down. The brush assembly is much cheaper to replace than the whole alternator.

i reckon you cant go wrong with an EA falcon alternator if you can get one cheap, they are easy to mount, you dont have to change anything except maybe the length of the fan belt and you can take out the regulator, you then have 75-85amps recharging which is heaps my car will idle or drive with the cutoff switch turned off which means the battery is isolated from the system, thats power!!!, probably not safe though cause it means my cutoff switch is useless if the motors running in the case of an accident.

Well hello again, seems like the induction is good, vacuum advance is good everythings good alt light......regulator maybe,,,,,,,hmm get the voltmeter out,,,,,,see how many volts you're getting with the motor off , then start up the car and see how many volts there is...if its below 13 its not enough charge.... but if its above 13 volts its charging,,, if its over 15 then the battery is overcharging and shortens the life of the battery dramatically. Theres the theory anyways....and its normal on a lot of cars to give the engine a rev to get rid of the alt light.....its to kick the regulator on by increasing the voltage (revs). Voltage regulators don't usually work when its below 13 volts,,,,when it gets between 13 and say 16 volts then the regulator works and turns off the alt light. Anyways I know I talk to much, but heres the theory anyway. Oh and if the battery is below 12 volts....then you need to get a new battery. lol

Quote:
Yes, this means the vacuum advance diaphragm is not leaking. The engine slows down from the leak (when you take the hose off). It doesn't tell if the advance is working (advancing) ... becuase the advance shouldn't "work" at an idle. It works above idle if correctly hooked up. Not to worry though, it sounds good.

The voltage should be 13.5-14.5 volts at 1200 rpm or above.

Over 14.5 is overcharging, replace the regulator.

It shouldn't drop below 12 volts at idle. If it does, make sure the belt is tight enough. Also check the brushes in the alternator, they are just a few dollars. If they are warn too much, revving it up will work for a while, until they wear more when it stops for good. You can tell by how far they stick out when the alternator is apart. To put it back together, use a straightened paper clip to hold the brushes back.

As pointed out, low voltage isn't usually the regulator, it's almost always the alternator. A bad diode can also cause low voltage, making the light come on at low speeds.

I tested that battery and Alt at idle and it was a bit over 13 Volts. I stuffed around at the back of the ALT and made sure all wire's where tight etc but I touched the power nut on the bottom and the fuel line, got a boot and pulled the guts out of the small wire from the battery. Took a while to find it aswell.

I tightend up the fan belt but found that the ALT light stayed on almost all of the time. So I backed it off and its back to giving a little rev for the light to go out.

I have a mate who is an auto sparky I might ask for "mate's Rate's" job ( a few Beers) , but I dont like to ask for help. But I may have to as I have never pulled an ALT apart before. And have a bad habbit of throwing stuff around when things go wrong !!

Regards & Thanks
amshaw

G'Day All,
Sorry guys I forgot to thank you all for the idea's/help !!

Regards
amshaw