Outer Limits 4x4 Board

Hey all.. my car is a TD42 GQ.. it was originally charging at 15volts..
i thought simple fix.. replace the alternator - as it had an internal reg, and was well and truly past its use by date.. full of rust etc
now..
Replaced the alt with a brand new one ($$$$) bolted it all up, and its still charging between 14.9 and 15 :( :( :(

is there something else i should be looking at??? and removing/replacing/swearing at???

i wanna go wheelin and electrical stuff gives me a headache lol

help me outers knowledge pool..

Check wires and plugs bw battery and alt. A bad wire/connection might be making the alternator sense less voltage.

hmmm... well the +ive terminal on the batt is pretty average.. it was overcharging for so long that the terminal's corroded, that could be the simple solution i was searching for??

Maybe, but to be honest I'd be looking more at the smaller wires coming off the alternator, especially the battery sense wire.

Also the grounding of the motor and the grounding of the alternator to the motor.

its sonds like the battery sense wire is sensing the batteries are low on charge like chimpboy said

I told Ryan to check the over all condition of his battery, as maybe the wiring is right, but maybe the battry is fubar,

could this be right?

I can't imagine how battery condition could send the charge voltage that high.

I think the chimp is on the right track - I would suspect the sense line, presuming the GQ has one.

-Scott- wrote: I would suspect the sense line, presuming the GQ has one.

IIRC it's a hitachi unit with an S terminal (sense) and an L terminal (lamp).

One way to test would be to just run a new one but a visual/physical check first mght be easier.

hmmm... ok well i checked all the wires, and nothing seemes damaged, there is one thin wire coming off the back of it (attaches to the same threaded stud as a thicker wire) and this wire goes to a small brown nissan labeled box (bout half the size of a match box) then out of this it goes back to earth (on the side of the alt)... but even with this unplugged it made no difference?? or does that mean that its buggered and i need a new brown bit?

sorry for the basic terminology but wires are not my speciality - i can wire em up but problem solving sucks lol

the only other wiring i have going to the alt is a big grey plug, and nothing really seems corroded or broken, except the brown box connections are a little old looking, looks as if its been on there since before time?

thanks for the help guys

Can you give us a description of the back of the alternator... maybe the make/model as well. It might help. It might not though

I do not recall a box like that on my GQ, is yours a TB42 or something else? Carby, injected..?

na turbo diesel... ill go grab the numbers and some info off it..

ok...
its a OEX brand alternator (brand new... even says so on the sticker )

numbers are
as they appear on the lable

DX HXA007
DHBT

its got a big grey plug that plugs in from my factory loom into the side next to the vac pump - has 2 wires, one thick white, one thin white/red

then a threaded stud on the back, where there's another thick white, and a thin white/purple.

the white/purple goes into the small brown box, which has its own earth wire to the alt housing.
i then have a black earth from my nissan loom going to the same spot on the alt housing.

the brown box has 2 terminals (the white purple and a -ive.)
and the only numbers on the back are 2.2. then a few symbols...


hope that makes sense,,, phuck i wish i had a digi camera it'd make life so so so so so so much easier

My TD42 Turbo charges at about 15 volts..... 1 Volt higher then i would of expected but it always has.... it hasnt bothered anything????

Screwy

yea mines corroding terminals on the battery and making a mess of things cause of the overcharging lol

yeh ok then fair enough, i thought about investigating why mines doing it but its not causeing dramas yet, my aftermarket duel battery indicator says its on the high side of normal but still in the green so when it starts bothering shit like urs i guess ill sort it out...

interested to know whats causing it now though.... seeing as u replaced the regulator, that would of been the most likely choise....

I only have a wiring diagram for petrols here but to me it looks like you need to zero in on the two white wires. If it's like the petrol they should hook together in the loom and then go to the battery via a fusible link (or maybe two).

If I were sure the diagram was basically the same for the diesel I would suggest putting a new "extra" wire from the battery +ve terminal to the threaded lug on the alt with the white wire on it, and see if this changes what happens. However I would be a little bit wary of this in case there is some difference with the diesel.

I think the white-red wire is your chg lamp (on my diagram it goes to the "comb. meter" and the brown box might be to do with your tacho signal since the petrol doesn't seem to have this, but again I am really not sure.

Do you have a multimeter? It would be interesting to check the voltage at the battery, and check the voltage at the alternator end of the white wire, and see if they are very close or not.

the diesels dont have a tacho off the alt, ther tacho is taken from a sender in the timing case cover,

unless the alternator is off something else

According to the workshop manual, voltage is regulated at 14.4-15.0 volts.

I would suggest there is nothing wrong with it.
Just replace the damaged terminal and your all done.

Cheers,

Micko

hmmm.. well hopefully your right, if its charging normal then i wonder why the terminal's corroding, but seeing as i have a new alt now i guess it could be fixed n just needs a terminal - ill replace the terminal and keep you updated

thanks heaps for the help people

Cheers
Ryan

did the new terminal fix the problem...

if not then the battery may be on its way out

dave

well.. not too sure yet lol.. got new battery and new terminal etc.. and my motor went kablamo - so i wont know 100% till the new motors in (should be on sunday if all goes well woop woop
wish me luck lol

MICK77 wrote:According to the workshop manual, voltage is regulated at 14.4-15.0 volts.

I would suggest there is nothing wrong with it.
Just replace the damaged terminal and your all done.

Cheers,

Micko

x2.

Also corroded term nothing to do with charging volage.
A small amount of acid can wick up the post and start a real mess.
Always keep the terms clean, very hot mild soapy water and a spray of chain grease etc.

Another thing, always try a 2nd voltmeter to check your readings.
Bazzle

bazzle wrote:

MICK77 wrote:According to the workshop manual, voltage is regulated at 14.4-15.0 volts.

I would suggest there is nothing wrong with it.
Just replace the damaged terminal and your all done.

Cheers,

Micko

x2.

Also corroded term nothing to do with charging volage.
A small amount of acid can wick up the post and start a real mess.
Always keep the terms clean, very hot mild soapy water and a spray of chain grease etc.

Another thing, always try a 2nd voltmeter to check your readings.
Bazzle

correct. high voltage wont damage your terminal - not until it is high enough to arc to something close by - VERY VERY high. Excessive current will - probably caused by a crap (high resistance) joint at terminal due to acid, terminal damage etc. Current draw would actually be lower due to the power draw on vehicle remaining about the same and voltage increasing...

also bicarbonate soda in water works a treat for initial cleaning then oil with a tectol or fish oil spray of some sort.

Might be a stupid point, but if you're reading the voltage from the standard dash gauge on some models it may be that it's not accurate ( i know for sure mine reads 2 volts higher ) and also check the batteries in you multimeter if you're using one and your still worried, if the batteries are a little flat it can also cause messed up readings