freewheeling tensioner pully

I recently changed the oil and filter and noticed when I shut off the engine there is a pulley which keeps spinning above the other belts and doesn't appear to be serving a function. Is this set up wrong?

How big? All pulleys are driven off the crank shaft so all should stop with the engine?

it's about 10 cm. it's the uppermost pulley just above the crank. Is it the air conditioning pulley? Or maybe that's further down and has a hole in it. I know it serves a purpose and last time I did the oil, I don't remember it continuing to spin after I shut the engine off. I'm thinking the guy who did the timing belt last in May perhaps, maybe- he did not tension the belt right. I need to have another look at it. The engine is running fine and I have not used the air con since 2010 so...I dunno right now.

Not sure how your engine is set up, but it sounds about the right size for an adjuster pulley. If it is spinning then the belt is not tight enough, and if that is the case I'm surprised the belt has not broken causing damage interference with the other belts/fan/rad.
Get you A/C in use, helps no end with clearing the screen in the cold and frosty winter.

ok when it's light out I'lll take another look. That's right you are in foggy old Bristol...similar weather as to here doesn't mean we feel affectionate about it...the air con could chill out the windows nicely and there are certianly enough of them

looks like the drivers seat has to be taken out to make the pulley rest on the belt

I would not worry about this pulley.

It is free wheeling beacause the belt is not touching it once the engine stops- the belt is the Air Con drive belt and it is the longest belt on the engine.

Mine does it and my belt tension is to spec, the pulley stops the belt from whipping and therefore stretching.

Ypu will see that if you tighten the belt even more i.e. over tighten it, it will not touch the pulley when the eogine is running.

LEAVE IT ALONE!!

So the pulley only touches the belt sometimes. Such as when the belt tries to whip. What is the spec tension of this belt?

Most of my Toyota A/C pumps have a free spinning pulley that is directly run from the crankshaft pully, with a standard adjuster pulley. The Belt tension is the same all the time. The A/C is engage by means of a clutch on the pump pully.

Other Toyota pumps have been cog driven.

If you are talking about the wheel John refers to please don't worry. Its just a idling wheel to stop the belt bouncing.
The belt will only whip badly when the tension is loose.....when any long belt gets loose you will hear the loud ticking noise as it 'whips'.
Tension is usually that you can twist the belt 90 degrees without using mega force, but you don't want it too tight or bearings will wear prematurely

thanks for your answers. I'm going to have fun with my air con this winter and see if I can keep the windows clear

So this leads me to another question. I have the hot/cold box between the front seats. have any of you managed to make ice? Mine has ice cube trays with tiny ice cubes spaces (probably about 2 cm) . maybe enough to chill the little box for a couple of hours...you know what I'm thinking....

With the A/C fully charged the ice is ready after about 20 minutes. Used it once just to check, sold it with the same water in the ice packs.

The kettle on the other hand got used a lot and one thing I really miss with the Townace.

a town ace is for sale here (1989 w/114 km for 4600 loonies) with a hot cold box. I imagine it has the kettle too. I always forget to put on the kettle and when I get to where I'm going (for a take out coffee) I go, " oh ya?... next time."

No kettle in the Townace. No hot/cold box in my current Townace either, but it starts the best I've ever had, it runs just lacking the extra oomph of a SC, and stops when I want it to.