Old Skool Battery / Alternator question

[Crazy Dazz]

You'd think, after all these years, I'd be able to nut this out...

Old Skool set up in a Nissan Patrol diesel, so no sophisticated electronics.

Battery is flattish after sitting for around 10 days. There's power, but not enough to crank.
Jump start with difficulty, and take it for a long drive.
Following morning, dead again. Roll start and take even longer drive.
Few hours later, dead again, Roll start and long drive, during which speedo and gauges stop working.

Today:
Battery reads 10.6V. Power but no crank. Jump starts easily.
At modest revs, alternator putting out 14.6V.
At idle, alternator putting out 13.6V

Usual Suspects:
1) Battery is stuffed. (It's "sealed" type, so no checking fluids.)
2) Alternator not charging (perhaps intermittent??)
3) Some weird power drain (but there's no alarm, minimal electronics, etc.)

[Citroënbender]

I’d suspect a shorted cell in your battery. Charge to full and get it load tested against rated CCA.

[GasoLane]

Originally Posted by Crazy Dazz

Today:
Battery reads 10.6V. Power but no crank. Jump starts easily.
At modest revs, alternator putting out 14.6V.
At idle, alternator putting out 13.6V

Usual Suspects:
1) Battery is stuffed. (It's "sealed" type, so no checking fluids.)
2) Alternator not charging (perhaps intermittent??)
3) Some weird power drain (but there's no alarm, minimal electronics, etc.)

This tells me that it's charging but the battery isn't holding it...........turf it and get a new (bigger) one

[73 4V XB]

Originally Posted by GasOLane

This tells me that it's charging but the battery isn't holding it...........turf it and get a new (bigger) one

^^^this. I drove for 4 hours no trouble. Stopped for fuel and that was it. Had to be pushed out from the bowser to try and jump start. Took RACQ in Gin Gin to get it going again, wouldn’t jump start from a car. He tested it out on the side of the road and everything was good. Off I went to Gladstone, turned off and that’s all she wrote new battery sorted and it’s all good.

[Crazy Dazz]

Ok, so fitted Brand New Century battery.

A few days later, we're right back where we started.

[73 4V XB]

Originally Posted by Crazy Dazz

Ok, so fitted Brand New Century battery.

A few days later, we're right back where we started.

It must be drawing power from somewhere. Something like a glove box light or similar.

[hayseed]

Originally Posted by Crazy Dazz

3) Some weird power drain

Time to get the Multimeter out.........

[marty351]

Do the accessories turn off when key is in off position?

My old corolla did this for 3 months for no reason, would flatten battery within 18-24 hrs, then fixed itself. Gremlins.

[aussiblue]

Check for shorted rectifying diode in alternator e.g. https://www.youtube.com/watch?v=2x0o4-bNCvY
https://www.youtube.com/watch?v=dhf6IdBbE3Y&t=120s

i.e. check the alternator with the diode function of your multimeter in both directions with alternator completely disconnected from the wiring harness between the case (ground) and the connector (thickest wire) for the battery charge. You should not get a reading in one director, or the same reading in both directions (when you swap the location of the positive and negative multimeter probes).

Does battery warning light go on with all the other warning lights as it should with ignition on engine off? If not, that's also usually a good indication you have shorted an alternator diode to earth.
__________________

[Citroënbender]

A weak alternator can just be poor brush contact, eventually this risks stressing the regulator but you can probably catch it in time.

Any chance you can share a picture of the battery terminals/posts as assembled?

[Crazy Dazz]

Oh, forgot to mention, damn annoying thing is that the Alternator is probably less than a year old.

And just to expand on the problem; driving after a normal start, with headlights and fan running, loses so much power that gauges stop working.
Nixed the lights and fan, and after a couple of minutes gauges back up.

So its either some massive short/ power drain, or the alternator is flakey (again.)

Originally Posted by aussiblue

Check for shorted rectifying diode in alternator

Ok thanks, I will have a look.

[Itsme]

Originally Posted by Crazy Dazz

You'd think, after all these years, I'd be able to nut this out...

Old Skool set up in a Nissan Patrol diesel, so no sophisticated electronics.

Battery is flattish after sitting for around 10 days. There's power, but not enough to crank.
Jump start with difficulty, and take it for a long drive.
Following morning, dead again. Roll start and take even longer drive.
Few hours later, dead again, Roll start and long drive, during which speedo and gauges stop working.

Today:
Battery reads 10.6V. Power but no crank. Jump starts easily.
At modest revs, alternator putting out 14.6V.
At idle, alternator putting out 13.6V

Usual Suspects:
1) Battery is stuffed. (It's "sealed" type, so no checking fluids.)
2) Alternator not charging (perhaps intermittent??)
3) Some weird power drain (but there's no alarm, minimal electronics, etc.)

After reading all the posts here I think an auto sparky is what you really need!

[Franco Cozzo]

Charge up battery (with a battery charger) then disconnect it, multimeter into A switch and connect it in series with the earth terminal on the battery (negative terminal to negative probe on multimeter, positive probe to negative terminal on battery) so the earth is connected THROUGH multimeter.

With the car off it should be under 0.05A draw.

If it's above you got dramas with something staying on - first thing to check is interior lights, glovebox light, then any aftermarket crapola.

Aftermarket stereo is a common problem.

If that's not it, you go through the fuse panel and pull out fuses one by one looking to see if anything effects the reading.

Also with the new alternator, make sure battery is fully charged, start car, all accessories on, fan on full, multimeter on 20V, hazards, AC if it has it, stereo up loud, and measure voltage at battery under load at idle and at 2000 RPM.

Check the condition of the battery terminals and the body and engine earths while you're there, if the wiring is green or the terminals don't fit well then replacement time - VT-VZ Commodore battery terminals are the best in the business.

That new battery is likely halal if you've ran it down to 10V a few times but get it on a proper charger - the alternator won't be able to charge that properly.

From what you describe with the car losing gauges it sounds like bad engine and body earths, you've got very high resistance somewhere there.

While car is running repeat voltage test at B+ terminal on alternator and earth to alternator bracket/engine and compare with readings at battery terminals.

[LTDHO]

Originally Posted by Crazy Dazz

Ok, so fitted Brand New Century battery.

A few days later, we're right back where we started.

I went through 3 Century batteries in one year, each had a cell that failed dropping to 10v
Changed brand and issue gone!

[ebv8]

you said the alternator is 1 year old, In the last 3 years i have been through 6 alternators in my holden adventra.
first intermittently overcharged and cooked the battery and killed globes and all that great stuff
then i got chinese alternators off ebay and after a few that didn't charge i got a good one and it lastest 3 months
then i got an expensive (chinese)one from an auto elec and that lasted 3 years, thought f'it i'll get genuine and works great

anyway there must be a pretty big current draw to kill the battery that quick, get a volt gauge so you can view it as you drive and do all the current draw tests

[Crazy Dazz]

So ok, I think I have found a culprit...

First, I tested for phantom current draw. There is minimal, .013A.

Next I tested this car, with my TTG charging system. Even loaded up, Highbeams and fan running, my TTG at idle supplied 13.5V (via jumper cables).

THEN, I tested this car with the good battery, and using the hand-throttle to keep the revs up. Loaded up, with battery connected, registering about 10.5V.
Disconnect the battery and the output drops to 9.8V

I don't know precisely how it works, to explain why it appeared better with a crap battery.
But this would seem to support the theory that the Alternator (despite being rated at 120A) simply cannot support any kind of load, and hence running lights and fans, even whilst driving is draining the battery.

And yes, to my shame, this is a POS ebay Alternator. Lesson Learnt.

Can anyone recommend a good brand and supplier of an Alternator?

[Citroënbender]

Hang on, you unhooked the only battery with the alternator spinning and motor running?

[11ford11]

Check for battery voltage at main heavy alternator wire

[Crazy Dazz]

Can anyone recommend a good brand and supplier of an Alternator?

[Franco Cozzo]

Genuine is good, go with what ever the genuine unit is.

Alternative OEX brand from Ashdown Ingram or JAS Oceania's own brand.

Avoid Jaylec from Cooldrive Distribution - they're junk.

[Citroënbender]

OEX is a bit hit-and-miss for me, some of the AC evaporators are less than ideal. Good relays.

What model Patrol, which engine?

[coo]

Also, check your battery and earth cables between the battery and alternator. Plus the 'fuseable' link.


If there is bad crimp/ join/ connections, there will be a voltage drop.



Or add a temporary heavy duty cable from the alternator output to the battery. The will bypass the possible suspect wire.


Never disconnect the battery when the alternator is turning. It will kill the internal electronics because it looses is sense voltage and cranks up to max.... letting the smoke out.

[roKWiz]

Originally Posted by 73 4V XB

It must be drawing power from somewhere. Something like a glove box light or similar.

One of my trucks had a parasitic drain from the alternators, took a lot of messing about to realise it.
Ended up replacing it with a JAS Oceania. (Jap truck ones need the vacuum pump on the back for exhaust brakes.)

[Citroënbender]

Yes, it’s not uncommon. A shorted diode, melted solder that’s bridging connections, thick heavy oily carbon residue that conducts, a cocked brush from wearing to nothing.

I’m one for rebuilding them if a name brand to begin with - Bosch, Denso, Mitsubishi, Valeo and Delco are all well supported in aftermarket and genuine parts from the front pulley through to the SRE bearing and back overcap.

[roKWiz]

Yep name brands are better, but did have a good experience with auto8 stuff (ebay) fortunately their distribution/retail store is in Wangaratta.

As Mr Franco mentioned that chinese, Jaylec guy on ebay sells junk, I didn't know and bought an alternator which overcharged at 19 volts. he wouldn't accept return once used.

[Citroënbender]

Are they (Auto 8) for real? That’s shifted my impression.

I’d always assumed due to price it was counterfeit stuff with a PO Box in Wang but probably shipping from Malaysia.

[roKWiz]

Yep I was there a couple of weeks ago buying a new starter motor for the van they sold me a genuine Bosch but could have bought a slightly cheaper Auto8. They have a large fully stocked warehouse retail store.
Sinclair drive, Wangaratta (google them in Wang)

[Franco Cozzo]

Originally Posted by roKWiz

One of my trucks had a parasitic drain from the alternators, took a lot of messing about to realise it.
Ended up replacing it with a JAS Oceania. (Jap truck ones need the vacuum pump on the back for exhaust brakes.)

The vac pump alternators are always low on amperage and high on cost, its common on some older Jap 4x4s as well.

I wonder if an electric vacuum pump like some Euros have fitted would work rather than the crapola mechanical pump on the back of the alternator?

Jaylec is Cooldrive Distribution's house brand - they're cheap and nasty, I've had multiple DOA.

[Crazy Dazz]

Unfortunately, the problem is not that unusual.
What misguided me originally was my presumption that "FMD it can't be the alternator AGAIN", followed by some misleading tests that seemed to show it was (at that time putting out reasonable voltage.)

And the battery was old.

Being a (oldskool) Diesel, it has negligible current draw and runs fine, until I put the headlights on. When the Alternator simply can't supply enough current.
Now yes, that could be down to dodgy wiring somewhere between the alternator and the lights.
However this alternator is rated at 120A. There's no way it's pulling that, even with bad connections.
Also, I was able to run it all, via jumper cables, from my own car, with a miniscule drop from 13.6 to 13.5, at idle.

And as I said, we've had the problem before, instantly fixed by new Alternator. Just our bad buying POS Alternator off eBay.

[Crazy Dazz]

Originally Posted by roKWiz

Yep I was there a couple of weeks ago buying a new starter motor for the van they sold me a genuine Bosch but could have bought a slightly cheaper Auto8. They have a large fully stocked warehouse retail store.
Sinclair drive, Wangaratta (google them in Wang)

ok, scratch that, Auto 8 have genuine Bosch, with 5 yr warranty for $289
sold!