Saturday, 29 September 2012

My cooked altenator stator

Well I didn't want to have to rip it out, and it wasn't until I was totally sure that it was this part (cos its damn annoying to get to).

The final clue in my diagnosis was that there was continuity to ground from each of the stator ouptut points. Since they are floating, this should not be.

After pulling it out I can see the problem clearly.

So its time for a new stator.
You can read about the install here.


Noons said...

Is this the one from the scooter?

obakesan said...

sadly. And it seems also more common for Yamaha to do this too

Noons said...

Bad ventilation or just plain under-engineered are the usual two reasons.
I do recall you mentioning something about it being hard to reach, perhaps that causes less cool air to go past it?

obakesan said...

Nope, its embedded in the engine. So it sits in the oil of the engine. Seems well known and decades ago with another Yamaha was told it was symptomatic of poor oil change regime way back then.
Probably the same thing now too

Benny Huang said...

I'm having the same problem as yours now. So may I check, any idea if the 09 model Tmax stator/generator fit in the 01-03 model? Since the engines are relatively similar? I'm having problems finding the stator. Did you change original or afrermarket stator?

obakesan said...


my choice was to go original or get the stator rewound. The rewind was quite cost effective at $150 vs the $500 for the stator. However due to a few other issues (like time) I chose to buy an OEM one. I also had trouble finding an aftermarket one which was significantly cheaper than the original. I also felt that the coils may be 'cooled' better with them being more exposed than some of the aftermarket but I have no evidence to back up that feeling.

If I was doing it again, I'd pay for a rewind.


obakesan said...

I just tossed out the original part so I can't even measure it for you. Yamaha should be able to tell you if the other models fit.