Alternator questions

[Gee]

I been busy today testing the condition of my alternator and battery and am clueless about what the results mean. Battery is fine but its the alternator I'm worried about. The alternator is charging without any electrical components turned on. Stereo on- ok, plus lights- ok, high beam alone- not charging, aircon alone- charging as long as its not turned right up, spotties- not charging. When ever the tester would indicate the alternator isn't charging the idle would become very rough and the rpm would drop (the triton has been doing this for as long as I've owned it- about 7 months- and I've never had a flat battery).

What on earth is this telling me????

alternator output not up to specs?,
too small an alternator?
As far as I know it is the original alt (65 amps) and shouldn't it be able to support all the standard electrical components.

[murcod]

Sounds like the alternator isn't outputting enough current. Does revving the engine up to around 3000rpm improve the reading? You won't get 65 Amps out of it at idle.

[Gee]

David, haven't tested amps at 3000 rpm- (car in shop today) but the headlights and the like are definately brighter when crusing- lights dim at idle. So yes I'd say the alternator charges better at higher rpm. What does this tell you?

[-Scott-]

Fan belt tight?

[murcod]

It seems to be behaving in a normal fashion (carefully worded reply! )

Do you know any other Triton owners who you could compare your's to? Also, why were you testing it- you said you've never had problems with a flat battery?

[Gee]

David, this all stems from another problem- white smoke on start up and theories about the alternator not supplying enough charge for my glow plugs- if you want the full story refer to "white smoke- a concern?" in the shitabishi forum- that's a bit harsh I know and I really do like my triton I'm just having a few dramas at the moment

[Bush65]

David, this all stems from another problem- white smoke on start up and theories about the alternator not supplying enough charge for my glow plugs- if you want the full story refer to "white smoke- a concern?" in the shitabishi forum- that's a bit harsh I know and I really do like my triton I'm just having a few dramas at the moment

White smoke could be glow plugs but I dont see what the alternator output has got to do with this (didn't bother reading that other thread). The battery supplies plenty of current to heat the glow plugs without the alternator.

If your glow plugs are ok, you probably should look at cylinder compression and injectors before the alternator.

[Gee]

John, in my other thread I explained that I had already had the injectors checked and serviced in an attempt to solve the white smoke on start up. It's not a compression problem either because then it would blow white smoke all the time- my triton blows no smoke whatsoever apart from start up. Secondly, I checked the alternator because in another thread a GQ owner had similar starting problems and found that the current from the battery didn't go directly to the glow plugs but via the alternator and a problem with the alternator was preventing the glow plugs from warming. So I thought it would be worthwhile checking the alternator. I dunno, maybe the two are completely unrelated....that's why I'm asking.

[Bush65]

Gee, what did they report about the condition of your injectors, as they were when pulled out? Were they good before you took them out? If not your bores etc. could be damaged, resulting in lower compression.

You could have a compression problem, and not blow white smoke when the engine has warmed up. It sounds like you haven't had the compession tested. If the injectors and glow plug system are ok, thats where you should be looking.

I'm not up with many different glow plug systems. Those I know heat the glow plugs before the starter motor is powered, it only makes sense with them to be powered from the battery.

Is the Trinton direct injection or indirect? Direct injection hardly need glow plugs, unless your in pretty cold parts.

Not saying you dont have alternator problems.

[Woop]

Check brushes in ALT ok, diode pack ok, regulator not faulty. Can you see the charge lamp glowing very dimly when idling with no lamps on? You'll need to check this in the dark as its very difficult to pick in the daytime. From past experience, a faulty diode can cause this problem and unless the alternator is heavily loaded, dosent show up. Also, the output voltage tends to go higher than normal as well.

Nick

[Tas_Dean]

David, haven't tested amps at 3000 rpm- (car in shop today) but the headlights and the like are definately brighter when crusing- lights dim at idle. So yes I'd say the alternator charges better at higher rpm. What does this tell you?

I would say that the diode pack or the regulator is on it's w
ay out. once the alternator has been excited (some alternators depending on the gearing will require you to lift the revs up off idle to get them started, ie. excited) the lights shouldn't dim between idle and full noise. IF there is a problem with the alternator, you may find the voltage goes too high and you'll start blowing lights, particularly using high wattage driving lights (eg 130 watt globes). I have had the same problem before!

However, I wouldn't expect this to cause any problems with the glow plugs, unless your battery is not charging properly. I would however, suggest getting your alternator fixed first. Get a price on repair, and also exchange rebuilt. I got two alternators for a bloke's boat the other week, for $180 each. Repairing the alternators was going to cost $130 each.

Cheers, Dean