Alternator Fire! Any ideas on the cause?

[UKcelicaman]

Hi,
I have a 1990 Celica 2.0 GT-i 16 (ST182R)

Everything's been great with it till yesterday when the alternator caught fire!!

Luckily I manged to put the fire out before any major damage was caused...

Being a person with about 5% knowledge of auto electrics, I wonder if anyone has had the same problem and known what the cause was?

I guess it could be just the alternator seizing up, or possibly something else?

Maybe the regulator malfunctioning? Is the regulator built into these things?

When I first drove off, the oil light came on, then the battery warning light, they both went out, and just after that I smelt the fumes and saw smoke coming from the bonnet (hood). PANIC!!

I will be getting a replacement alternator, but wondered if there should be anything else I need to check?

Next problem: How do I get the big plastic wire block off? its the circular one holding 3 cables at the front of the unit.
Maybe its melted? Or is there a knack to removing it?

Update:

I have managed to get the connector off, yes, it was burnt and had fused onto the housing!!





I'm not sure if these pics will shed any light on the cause?

Ask me about 1950's Ford Anglia engines, no problem, but modernish Toyota?

[ximporttunerx]

Originally Posted by UKcelicaman

Hi,
I have a 1990 Celica 2.0 GT-i 16 (ST182R)

Everything's been great with it till yesterday when the alternator caught fire!!

Luckily I manged to put the fire out before any major damage was caused...

Being a person with about 5% knowledge of auto electrics, I wonder if anyone has had the same problem and known what the cause was?

I guess it could be just the alternator seizing up, or possibly something else?

Maybe the regulator malfunctioning? Is the regulator built into these things?

When I first drove off, the oil light came on, then the battery warning light, they both went out, and just after that I smelt the fumes and saw smoke coming from the bonnet (hood). PANIC!!

I will be getting a replacement alternator, but wondered if there should be anything else I need to check?

Next problem: How do I get the big plastic wire block off? its the circular one holding 3 cables at the front of the unit.
Maybe its melted? Or is there a knack to removing it?

Update:

I have managed to get the connector off, yes, it was burnt and had fused onto the housing!!





I'm not sure if these pics will shed any light on the cause?

Ask me about 1950's Ford Anglia engines, no problem, but modernish Toyota?

could it possibly be that your alternater was goin out and surged too much electric for the battery and making that electricity catch fire? not too familiar with that happaning

[toyomoho]

The cars electrical system draws off the battery, the Alt output does to the battery. If too much power is asked of the Alt a fuse going to the battery will blows. Typically the regulator is built into the Alt.

The Alt could have had an internal short or the output wire shorted to something, perhaps the case.

Separate the wires, check all fuses including fusible links.

The harness plugs into the Alt via a socket. You can find another plug, perhaps off a junker. Cut the plug off leaving extra wiring then splice into your current wires.

The back of the Alt case may also have individual output studs that can be wired directly to, look at what ever is left of the case.

[UKcelicaman]

Thanks for your help guys!

I'm just trying to track down an alternator and connector, then will attempt to refit and try again!!

Give me a PC, a mouse and Photoshop and I'm the biggest knowitall around, but auto electrics?...... ARRGH!!

Cheers
Ron

[toyomoho]

The AutoZone website should have info on how this cars charging system works plus wiring diagrams.

[bpodskalny]

mine did the same thing last week. with the engine off and the keys out of the ignition. the only thing i could come up with was the insualtion on the windings gave out, grounding battery voltage to the case and getting it mighty hot. melted my brushes, i found carbon tracks on the regulator. just replace it, it has an internal regulator, you shouldnt have any problems.