Page 1 of 1

alternator probs?...?...??

Posted: Mon Feb 06, 2006 2:41 pm
by the plough
Was drivin along a road when i noticed my warniung lights were all on..opon inspection i found a 6mm wire on the alternator to be burnt off. Drove it home fine and went to replace the connection and there was that much heat the nut and bolt almost welded together. Finally got it on and started and the problem remains....the battery it not losing charge and the alternator volt output is gradually increasing in small amounts... for as long as the engine is runnin it keeps climbin
HELP??

Posted: Mon Feb 06, 2006 3:44 pm
by Top Cat
A 6mm cable is a fairly major cable, capable of handling high amps.

For one of them to burn out I would be looking for two things..........either there was a very bad connection causing all the power to be drawn through a small percent of the 6mm cable or there is something causing it to overheat that is drawing more than what the 6mm is capable of.............this could include a short somewhere.

Have you just added extra stuff to the truck and wired it in to operate direct from the alternator?

It is also possible that there is an alternator problem as well.

Posted: Mon Feb 06, 2006 3:53 pm
by the plough
i think i have narrowed it down to a bad connection..so i replaced the connected cleaned everthing up but the charge light still remains on in the dash??

Posted: Sat Oct 10, 2009 7:55 pm
by cooki_monsta
how did u fix this?

Posted: Sat Oct 10, 2009 8:33 pm
by presto
check all your fuses too. there would have had to be a pretty bad connection to generate enough heat to melt the cable. where abouts on the cable was it damaged? the whole thing evenly or just on the alternator end?

Posted: Sat Oct 10, 2009 8:37 pm
by chimpboy
Let's finally get this bitch of a thing back on the road after three years!

Posted: Sat Oct 10, 2009 8:57 pm
by -Scott-
chimpboy wrote:Let's finally get this bitch of a thing back on the road after three years!
Yeah!

Although, the plough hasn't posted since April last year, so we may be waiting a while for him to come back & read this. :lol:

Posted: Sat Oct 10, 2009 9:08 pm
by cooki_monsta
damn cos im having this problem with my gq patrol :@ but they run the same alt, im leaning towards brushes or reg. are they easy to change, and parts, where can i get em?

Posted: Sat Oct 10, 2009 9:56 pm
by chimpboy
cooki_monsta wrote:damn cos im having this problem with my gq patrol :@ but they run the same alt, im leaning towards brushes or reg. are they easy to change, and parts, where can i get em?
What problem are you having exactly?

Posted: Sat Oct 10, 2009 10:30 pm
by cooki_monsta
ah, charge light stays on, volt guage sits at 12 or just below, oil pressure wont read on my guage, unless i hold my revs at 2500 or above, then i get an oil pressure reading, and my batt light turns off, but alt still wont charge

Posted: Sat Oct 10, 2009 10:35 pm
by presto
cooki_monsta wrote:ah, charge light stays on, volt guage sits at 12 or just below, oil pressure wont read on my guage, unless i hold my revs at 2500 or above, then i get an oil pressure reading, and my batt light turns off, but alt still wont charge
is it petrol or diesel? internal or external reg? how confident are you of doing repairs yourself? can give instruction if you are mechanically minded, if you're not confident in being able to pull it off and apart, any answer given would probably mean you'll need to take it to an auto elec anyway.

Posted: Sat Oct 10, 2009 10:47 pm
by cooki_monsta
its petrol, sorry should have said that, very confident, its got a gu 4.5 alt in it and i would prefer not to replace it, im an elec apprentice so i have no probs doing wiring etc

Posted: Sat Oct 10, 2009 11:05 pm
by -Scott-
cooki_monsta, I would guess your alternator has no field current, so it is only using residual magnetism to generate current. This magnetism is significantly lower than normally generated by the field current, so you need high revs to generate enough voltage to charge.

Beyond that, I'm not sure. Regulator, brushes, broken wire. Personally, I'd take it to an auto elec - but I'm getting lazy in my old age. :lol:

Posted: Sat Oct 10, 2009 11:27 pm
by cooki_monsta
very true, i was thinking stuck brushes, as even at high revs i still dont get a charge, or if i do its very minimal, they are a hitachi unit from memory? might pop down to my local auto shites store tomorow and try and get some new brushes and a regulator for it ... the saga continues

Posted: Sat Oct 10, 2009 11:43 pm
by presto
before you spend any money, check all the basics first. check voltage at the alternator so you know its not a dodgy connection to the battery and check you have battery sense to the reg. make sure the warning light goes out if the reg is unplugged.
if these check out, give the alternator a tap to try and loosen the brush if its stuck, if it starts charging this is most probably the problem.
is the reg easy to get off? if it is, disconnect the battery and pull the reg off.. it should be obvious if the brushes are warn. also have a look in the back of the alternator and check the slip rings - if the brushes arent making a propper contact the slip ring will probably look dirty. also check it for wear, if you can feel a lip then its best to pull it off and apart and have the thing reco'd (new bearings, machine slip ring and new reg). while its off an apart id take the rectifier/stator assembly to an auto elec and get the diodes checked.
how many ks has it done?

Posted: Sun Oct 11, 2009 6:15 am
by cooki_monsta
thanks mate that seems like a good starting point, it has only done prob 8,000 in my car, not that many, but it came off a gu with 75,000 on the clock