Alternator Overcharging

[Djaniero]

Just a quick update.

My alternator is still randomly squeaking . I can hear it speaking very slightly on idle. But then sometimes it randomly starts squeaking if I'm out driving normally - day time without lights on radio on.

I took it for a long ass drive after I fitted my alternator, but it doesn't seem to have made a difference.
Could I have dirt on the belt, or does it sound as if the belt is too tight?

Thanks

 

[dac69er]

could be a few things. are you sure its not the waterpump squeaking?

could be dry bearings on the alternator, sometimes the brushes make a squeaking sound on the commutator when worn too.

could also be the belt being too tight or too loose. what voltage do you have at the battery while the car is running and what voltage do you have I the morning before starting the car?

 

[Djaniero]

Managed to get this sorted. But my alternator fuse looks like its burning out again...melting :s. Does anyone know what could be causing this. After i installed the new alternator...i checked the voltage and everything was fine. I m going to check it again but kinda confused as to what it could be?

 

[weeJohn]

If it was burning before you replaced the alt then its possible the connectors are a little burnt at the fuse block and are not getting a real good connection. This will cause arcing and causes higher current.

 

[Djaniero]

How would i fix this...just by cleaning the connectors? Also if this was the case, wouldnt i have been getting a higher current as soon as i fitted the new alternator and fuse?The voltage was fine after i installed them both until now.
Thanks

 

[dac69er]

Voltage and current are diifferent. Voltages could be the same, but if there is a bad connection it can create a higher current draw. As the fhe fuse is the built in weak point of the system it can get hot before it blows. Sounds like it's right on the limit before it will blow. What rating is your alternator fuse? Could be as simple as it being the wrong one!

 

[Djaniero]

Ahh right. I get what you mean.
iirc it was an 80amp fuse i bought from here.http://m.ebay.co.uk/itm/231019431406?nav=SEARCH

 

[weeJohn]

Arcing causes current spikes, it takes a little more time than the length of a spike for a fuse to blow. Check the connections, file them flat if the lugs are uneven from arcing, make sure the connections are tight on the fuse legs.

There could also be a short in the wiring somewhere that is causing the high current load, if you connected the battery up back to front this can happen. There should not be a really high current load on the alternator fuse with nothing running but the engine if there is no faults. If the battery is goosed then it will draw a high current, if you can get a clamp type multimeter that measures current you can check the load on the fuse. A lend of a battery would check if this reduces the load.

 

[Djaniero]

Thanks for this guys. My electrician is popping over tomorrow, so hopefully we can get to the bottom of it.
The battery is about 2 months old, but I guess its worth double checking it.

If there is a short in the wire, would this be thr wiring harness which connects to the alternator or the wiring going to the fuse box?

 

[Djaniero]

quick update. Headed to halfrauds this morning and picked up a multimeter.

I've never done this before, so feel free to advise me if I did it wrong.

With the car off I got a reading of 12.7v .

With the engine running I got a reading of 14.5v
With the lights on, inc indicators etc, I got 14.6. When I turned on the heaters and radio it flutated between 12.8 a and 13v.

Do any of these figures seem wrong?

I took both the 50a and 80a fuses out, cleaned up the terminals, then replaced the fried fused with a new one. Took the car for long drive, checked the fuse box again, and no signs of the fuse frying this time?
Would be a good idea to check for shorts in the circuit still?

I'm not sure the cheap ass multimeter I have allows me to test the fuse either....I emember someone suggesting this to.

Also, see the pic of the 80a fuse and the 50a fuse below.



The red 50a one on the left, is an original toyota one, where as the 80a one on the right, is just an ebay fuse, but it has a different terminal. Would that make a difference at all?

Thanks

 

[dac69er]

good lad for having a go. sounds ok to me. if you arent getting any issues at the moment i would just keep an eye on it. could have just been a bad connection that your searching has sorted.

i wouldnt worry about testing the fuse with a cheap meter. it wont tell you much.

as for the new fuse, its probably just made like that to make it easier to fit on some cars, perhaps. i wouldnt worry about it

 

[Djaniero]

I know....6 months ago, I never would have dreamed of doing half of the stuff I've done on my starbo of late...good learning experience though!
Thanks again for the info.....Fingers crossed it was just a bad connection

 

[weeJohn]

I agree, good for you for having a go! The readings you are getting sound fine and so does that fuse. Worth while having a check next time the car is switched on for a time, open the lid of the fuse box and see if the fuse is warmer than others in there. If not I think YOU have sussed it, well done!

 

[Djaniero]

Back with a similar problem again lads. I was driving along the motorway yesterday, and all of a sudden the car lost all electrical power - what an interestimg drive I had back home with no indicators, lights etc!.

As soon as I got home, checked the fuse box, and as I thought the main 80amp slow blow fuse has fried again . The car has recently had a td04 kit plumbed in and I wired the wideband gauge into the cig lighter and wired in a new slimline fan....but surely this wouldnt cause that to happen would it?

I m guessing i need to go back to basics and check the voltage again on the battery?

 

[Jay]

Strange one mate.

The ciggy lighter and rad fan circuits have their own fuses so if those didn't blow I'd imagine they aren't related.

As you say, start at the start again and go with the basics.

Jay

 

[Djaniero]

Strange to say the least mate. I managed to bridge the terminals on the fuse with some wire - So I could wind the elec windowdows up and arm the alarm in the mean time. Can I test the volts with the fuse bodged like this, or shall I wait for the new fuse to arrive.

Totally off topic Jay, but I know you'll be able to advise....My exhaust is knocking in the centre section at the moment (Its a hks hi-power or similar). I took it to a friends garage to get it up on the ramp and have a look yesterday. They said that because the td04 decat is longer than the stock cat, my exhaust is hanging down lower and at an angle.....so I either need to get a custom system made up, or get a fabricator to bend the decat pipe up so the exhaust sits higher?

I thought I would double check though, because surely tonnes of the starlet boys over the years have fitted td04s and just use the same aftermarket system thet were using previously??

Thanks

 

[Jay]

Until you work out your electrical gremlin I wouldn't advise bridging the terminals like that. You could end up with more extreme damage or (worst case) fire damage.

Wait for a fresh fuse imo.

The exhaust issue would be caused by the downpipe of the td04 kit. There's a nunber of different kits, suppliers and fitments out there so it's hard to advise. If it were me I'd get what you have modified as best you can.

 

[Djaniero]

Thanks Jay.

Quick update...order a couple of Fuses and just fitted one. Volt readings are the same as before, but as soon as I turned the lights on the fuse fried again. Any ideas on what this could be?

A friend f mine had just had a look at it, and he said he is certain that this wire going to the 50amp fuse is causing my problem:



He said that the white wire o the left marked with the black marker is a live wire, and it is earthing somewhere. Can anyone tell me where that wire leads to from the fuss box?

 

[Jay]

This thread should assist mate:

http://www.toyotagtturbo.com/wiki/EP82wiring/EP82 Starlet Wiring and Connectors.pdf

It shows what everything looks like and where it leads to on a mk1 GT which should be enough for reference.

 

[Djaniero]

Hey Jay...we re in the mix trying to find out what the fault is. That pdf seems to be different to the wiring of my car...thats for a mk1 where as my car is a 1994 model. We have a thick white wire coming from the the main 50amp and 80amp fuses. Its showing as a earth/ground on the multimeter. Is this correct? My electrician is convinced that this is the problem as you should not have an earth going to a live fuse?

Thanks