Toyota Yaris Alternator nut

Channel Hopper

Channel Hopper

Suffering fools, so you don't have to.
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The other half's car came to a stop on Wednesday after the alternator (serpent) belt shed itself into the engine bay.

The cause appears to have been the alternator pulley nut unscrewing and dropping onto the road, disappearing forever. It's a T reg with airconditioning and 1 litre non-VVTi engine.

I think this is all that is needed but does anyone know what nut I should order ? Th thread looks to be about 12mm diameter, pitch unknown. There is about 14mm of thread in total and so I'm not sure whether the nut is held with a locking washer, or is one of those nylock jobbies.

I'm hoping alternators are generic and so the shaft size/composition is similar to others.

Thanks in advance
 
I wouldn't have thought it mattered; nyloc plus plain washer or lock washer and plain nut. Is it a simple pulley or multi V type? It's a while since I had cause to get my hands dirty there, but, should there also be a woodruff key to couple the pulley to the shaft? If you have an auto electrician anywhere close he may liberate one from a scrapper for a few beer tokens
 
Is the pulley still in place/available? If so, then I'd just go with a nylock type nut with thread locking compound. If not... hmm... probably easier to buy a new alternator. Also, some alternator pulleys are clutch pulleys - means they are free to spin one way on the alternator shaft but "grabbing" it when going the other way. This is used for reducing alternator belt vibrations.
 
The pulley is there (though it was a close call), no woodruff key that I can see, just from the nut to hold her on the shaft.
 
Found a nut that fits, but only after an hour of non access (the Yaris alternator is at the rear of the engine) I found it was the wrong diameter thread.

I found another in the parts bin earlier tonight, but it took about three hours to fit, one hour to check/clean/reassemble the serpentine through the right path of the pulleys, an hour to screw in the nut on the alternator and tighten (using a drill key to lock the alternator whilst tightening the 22mm nut, then finally adding a 10mm spanner on the shaft when it became visible) and an hour to scrub off the grease.

It is probably the only nut of its type on the car and the other half managed to lose it a few hundred yards from home.
 
Back again

The nut is still on the shaft, but what happened six months ago was probably a precursor to total failure of the alternator, as its seized solid. Thenut is still on the shaft, but the pulley has been working its way around until it has worn a groove in the shaft. The other half did notice the noise but decided not to do anything about it until the battery went flat.

I've managed to get the alternator off the engine mounting points and disconnected the wiring, but I cannot fathom how to get it out from under the bonnet without disconnecting a lot of other pipes or the drive shaft on the offside, there is no cavity it can come through.

Any ideas ?
 
Channel Hopper said:
The nut is still on the shaft, but what happened six months ago was probably a precursor to total failure of the alternator, as its seized solid. Thenut is still on the shaft, but the pulley has been working its way around until it has worn a groove in the shaft. The other half did notice the noise but decided not to do anything about it until the battery went flat.

I've managed to get the alternator off the engine mounting points and disconnected the wiring, but I cannot fathom how to get it out from under the bonnet without disconnecting a lot of other pipes or the drive shaft on the offside, there is no cavity it can come through.
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I've had a bit of success recently with how-to vids on youtube (removing and cleaning EGR valve in Clio II, replacing air filter of Scenic II). Sometimes the audio is in languages I can't speak but when all you need is the pictures this isn't really a problem.

In the distant past have resorted to Haynes manuals :)
 
And, off, without taking the exhaust apart.

I'll have a go at freeing it off first as the exchange ones start at over 100 pounds.
 
Oh dear, the nut I put on the shaft last time has got so hot it has more or less welded itself onto the shaft. The pulley has been loosened underneath but has been spinning for a while (the battery in the car is virtually flat), meaning the shaft is a good couple of mm less in diameter on one section. Even if I freed off the nut there would be virtually no chance of centralising the pulley before retightening.
 
Ebayd an alternator from a dealer ooop north, arrived and fitted

About forty pounds lighter, but at least the wife is no longer ordering taxi's to the supermarket.

(squeals a bit on starting, but I'm good at ignoring her when in that sort of mood......)
 
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