Alternator Not Charging

[Calum122]

Hello,

I did post this on UKSO but it's a little quiet on the answers.

Basically the story goes.

I took my alternator apart to rebuild the bearings.

Upon installation I omitted the plastic cup on the alternator and consequently the alternator shorted out and the was lots of pops and bangs.

Realising this I disconnected the alternator and refitted the plastic cup.

This is when I saw that the alternator stopped charging.

I took it off agian and bought new internals, thinking that I shorted it out.

Whilst it was off I tested to see if any current was being generated and I saw microamps across the power out.

See video

https://youtu.be/e4_JnyW25Rs

So I am happy that the alternator isn't faulty.

However it is still not charging. I have tested for continuity between the alternator and the fuse box.

http://i.imgur.com/2KTOht8.jpg

Upon investigation I noticed now power measured at the fuse box.

Can someone please help. I haven't had much luck with this car having only driven it 500 miles in the three years I have had it

If anyone has some ideas please let me know.

I tried searching but the search function seems broken, returns 404

 

[dac69er]

if you have no power at the fuse box, has your main fuse gone?

have you done an insulation resistance test on the coil windings?

 

[Calum122]

if you have no power at the fuse box, has your main fuse gone?

have you done an insulation resistance test on the coil windings?

I haven't tested the coil windings, but they were fine before hand.

Which one is the main fuse. I would be inclined to say its that to be fair. Or I hope.

 

[Calum122]

Also why would the car start if the main fuse was gone.

 

[dac69er]

if you have shorted something, then it could cause you an issue with the windings. do you have continuity between the 2 slip rings?

i would look through all your fuses.

you didnt mention the car would actually start. how does it start with no power at the fuse box?


for the cost of it, you might as well buy another working alternator to rule that out, then check all the fuses and go from there.

 

[Calum122]

Funnily enough, I didn't find any continuity through the slip rings (or the brushes)....

 

[Jay]

Firstly, I have very little experience with alternators so don't rely on me for any answers..

I've actually got a weird alternator issue I've been experiencing recently too:

-Driving along and both Cat temp and battery warning lamp come on intermittently
- Fit reconditioned alternator as I figure the original is goosed
- Lights go off
- Few weeks later I'm washing the car and notice a burning smell and smoke from the alternator
- Replace with a spare alternator as I figure the recon has been cocked up
- Driving along and both lamps come on again
- Alternator is definitely not charging the battery as I'm left stranded last Monday (ffs)

I'll be digging into it all next week but I had a quick check of fuses and it all seems grand at first glance.

So along the same lines as Calum's problems has anyone got any basics on how to diagnose the easy stuff? It's the first time I've had this sort of stuff happen so any tips would be awesome.

I'll certainly report back on progress just in case it helps out,

Jay

 

[Calum122]

Damn Jay I was kinda hoping YOU would have the answer LMAO!

I always considered you to be the definitive knowledge to the GT

Umm that's a compliment.

Hey, how hard can it be right?

 

[Jay]

Unfortunately everything I've learned has been the hard way - by experiencing it and having to bloody solve it.

This is just another fresh thing to get my head around so that sort of makes it a good thing.

Okay so I took a gander today.

I start the car and two warning lamps come on (cat temp and battery). To my knowledge these come on when the alternator isn't putting enough power to the battery.

First checked the belt was on and tight - all okay.
Then checked the connections. Plug is secure at the alternator end and both battery terminals are clean and tight at the other.
Then went through my fuses. Removed each one to make sure there was no corrosion hiding in the terminals. The ones that matter (ALT, AM1 & AM2) were good and showing continuity. The clear top on the ALT fuse was missing so I swapped out the fuse for a confirmed good one just in case there was any dampness.

Ran out of time for anything else but I'm thinking it could just be bad luck and I've got another faulty alternator. Will donor a good one and see if the fault migrates next.

There's a few manuals lying about so I'll see if there's anything worthwhile in there too. Research research research!

Does all this sound good so far?

 

[Calum122]

Hhmm, I was looking at the wiring diagram kinda hoping it to be AM1. But alas there is power to the rear cluster

 

[Calum122]

So I've bought another new alternator, shame as I was really hoping to have successfully rebuilt mine and learnt something.

I reckon if I didn't short it out it might have worked lol.

I will continue to rebuild this alternator and get it working mind you. I don't get defeated so easily lol.

But at least if I get a new one I can rule it out.

 

[Jay]

Found a section in a 4EFE manual in English here that explains how to rebuild one if you fancy a few pics?

There's also a bit about testing the charging system and I think I'm sort of on the right track with what I've done so far too.

 

[Calum122]

So that was the idea.

I rebuilt the thing from the ground up.

Either I rebuilt it wrong, can't see how to be fair.

Or when I shorted it I damage something.

the only thing left to replace on the alternator are the coils, and the brushes.

My thinking is I've damage something on the car.

Which I really hope not.

Should get the new alternator this weekend, fit it and fingers crossed.

Cheers Jay

Also there is a really good video on the Tubes for rebuilding the Denso alternator. Just FYI.

 

[dac69er]

does just sound like dodgy alternators. bad ground connections can also cause this issue as the alternator generally just grounds through the block.

sometimes the alternator can be charging ok, but the output to the warning lights doesnt work corrctly due to a bad regulator. have you tested the voltage at the battery whilst the car is running Jay?

 

[Calum122]

Aww man, I still haven't solved this.

To rule the alternator out I went and bought a brand new one, however unfortunately this still hasn't resolved my problem.

So really I am at a bit of a loss as to what the problem is now.

I only have the battery earthed to the chassis.

The new alternator has resulted in the battery warning light to come off.

But the battery, when the engine is running, has only 11.8V, it hasn't been charged for some time.

The fusebox still has no power across it.

I'm sure the fuse box under the cabin should have 12V across the fuse blades.

 

[dac69er]

you will want a ground connection to the engine block too. that wont help.

have you checked through all your fuses to make sure that isnt the issue?

i just had a quick google search and it appears toyota fuse all terminals to the regulator.

 

[Calum122]

It wasn't earthed to the block before but I have ordered a Buddy Club Racing Spec Condensor to see if this helps. It will come with an earth kit.

All the fuses have been checked with no problems.

Which regulator is this bud? The one on the alternator?

The battery light on the dash has gone out now that I have replaced the alternator.

 

[Jay]

Meanwhile I'm no further on. Other cars keep getting in the way - I now have a ruddy RX8 that's in the way..

 

[Calum122]

Love the rotary engine. Never liked the 8, one day I will own an FD3S

 

[dac69er]

It wasn't earthed to the block before but I have ordered a Buddy Club Racing Spec Condensor to see if this helps. It will come with an earth kit.

All the fuses have been checked with no problems.

Which regulator is this bud? The one on the alternator?

The battery light on the dash has gone out now that I have replaced the alternator.

yes, the regulator on the alternator itself.

i would definitaly make sure you have a cable from the body to the engine block. when i first did my 4wd conversion i forgot this cable on the first start up. i only had a very small wire connected and it got red hot after a few seconds running. if you dont have one fitted at all, that might be your issue.