The Current Driveway...

[TrabbieRonnie]

Hello all,

Question for the hive mind...  We've had a bit of trouble with the old Hilux Surf, specifically the brand new alternator.  My youngest was driving home and got a dash full of lights, shortly followed by a slight temperature increase (the alternator belts run the waterpump/fan also).  

On inspection, the alternator pulley was lying on the sump guard, it's retaining nut nowhere to be seen.  He wasn't far from home, so we let things cool down and drove on home.

A bit annoying on a new (and expensive) part, but we'd kept the old one so had a spare M14 fine pitch nut, and resecured it.  Bit of a hard thing to do up, you can't get to the front with an impact gun, so resorted to jamming a screwdriver in the front of the alternator and torquing up with the socket wrench...  No Woodruff key(?!) or taper to help keep the pulley on, strange but as per the original.  

Anyway, I didn't have any thread-lock, which will be applied when it arrives, so put a witness line across the nut and shaft, and instructed youngest to check periodically. 

He did so this morning before heading for work, and found that the nut had moved slightly.  I was summoned for a look, and assumed it had undone by nearly a full rotation, almost lining up again.  However, I couldn't get any torque on it, it is 'kin tight... therefore it appears to have very slightly tightened itself up?  I assumed that as the engine and belts rotated clockwise, the inertia of the pulley would effectively be trying to 'undo' the right-hand-thread nut over time, but apparently not?

Happy it's ok, just a bit puzzled.  And Toyota, just use a bloody Woodruff key would you please?  I know the original lasted 30-odd years, but still!