Big 3 Shorts Out - Toyota Nation Forum : Toyota Car and Truck Forums

s1138 · 08-07-2007, 12:29 PM

Like many I decided to upgrade the "big 3". The car is a '90 camry.

I used all 0 gauge wire.
I ran it from the Positive Battery through a 250A fuse and connected it to the positive on the alterator.
I then ran a cable from the chassis to a mounting bolt on the alternator. The long one on the front pointing towards the ground.
Finally I ran a cable from the chassis to the negative battery terminal.

I went to reconnect the negative terminal on the battery and all I got were sparks and a crackling sound. The 250A fuse blew, along with the smaller stock 80A fuse.

I've rechecked the wiring. Made sure the chassis points are bare metal.

What am I doing wrong?

Mr Marv · 08-07-2007, 02:10 PM

Quote:

Originally Posted by s1138

Like many I decided to upgrade the "big 3". The car is a '90 camry.

I used all 0 gauge wire.
I ran it from the Positive Battery through a 250A fuse and connected it to the positive on the alterator.
I then ran a cable from the chassis to a mounting bolt on the alternator. The long one on the front pointing towards the ground.
Finally I ran a cable from the chassis to the negative battery terminal.

I went to reconnect the negative terminal on the battery and all I got were sparks and a crackling sound. The 250A fuse blew, along with the smaller stock 80A fuse.

I've rechecked the wiring. Made sure the chassis points are bare metal.

What am I doing wrong?

Can you post pictures of how everything is connected?

Buurin · 08-07-2007, 02:39 PM

Quote:

Originally Posted by s1138

Like many I decided to upgrade the "big 3". The car is a '90 camry.

I then ran a cable from the chassis to a mounting bolt on the alternator. The long one on the front pointing towards the ground.

...

What am I doing wrong?

This is highly suspect.

Mr Marv · 08-07-2007, 05:51 PM

Quote:

Originally Posted by Buurin

This is highly suspect.

That's what I was thinking

s1138 · 08-07-2007, 07:26 PM

Where would be a good place to run that wire to?

edit:

Ok, I found an engine picture online and MSPainted it.
The Blue is the positive from battery to alternator.
The Green is the negative battery to chassis.
The Red is the mounting bolt off the alternator to the chassis.

http://img61.imageshack.us/img61/1434/big3ro4.jpg

Corollacrazy42 · 08-08-2007, 01:25 AM

Looks right to me.. but the only way those fuses are popping is if the wires are flipped...

s1138 · 08-08-2007, 10:10 AM

wires flipped?
I am not quite understanding that.

Curry · 08-08-2007, 11:08 AM

dissconect the one from the alternator mounting bolt and see if it still shorts.

[SMAN] · 08-08-2007, 11:33 AM

This is why it is allways good to meter your connections. I would get a multimeter and check the connection between your alternator and ground. If you see +12V, you know you shouldn't hook it up to there. In the long run, this will save you time, blown fuses, and a potentialy deadly hazard.

Corollacrazy42 · 08-08-2007, 06:31 PM

flipped... as in reversed polarity. Negative on the postive, positive on the negative nonsense.

Quote:

Originally Posted by s1138

wires flipped?
I am not quite understanding that.

Corollacrazy42 · 08-08-2007, 06:34 PM

Also.. I think you should connect your engine ground to the actual engine block and not the alternator. You may have a bad grounding point putting it on the alternator.

s1138 · 08-08-2007, 09:19 PM

Is there a specific place I should put the wire on the engine block. Or would any bolt do?

I did notice one thing today when I was looking. Originally, there was the positive to alternator. And then there were 2 wires running off the negative terminal. One went to the chassis, and the other mounted on top of the transmission.

Could I disconnect the negative to the transmission, and run a new wire from the transmission to chassis?

atobe · 08-09-2007, 02:34 PM

i think your blue wire is shorting out... only reason i would see a 250A fuse blow... your alternator only puts out 70A. also your red wire does basicly nothing.

there's a few grounding wires on the car.. battery to tranny,chassis as u stated... if you look near the alternator.. there's also another going from engine head to chassis. there's also another below the battery that connects the tranny to chassis.

what i did in my car was get a battery terminal and got 2 4 gauge wires.. ran one to chassis.. one to tranny... replaced all the other ones with some left over 10 guage wires. never did the alternator+ to battery+ though.