i was replacing ym water pump the other week, and replaced all the belts (aircon, waterpump, and alternater).

then a f ew days ago one of my mates 7's snaped a belt.
he said he was only running one (he doesnt want the air con) anyway.

but i went out and bought two belts (alternater and waterpump).

put them all on good and proper and now it works a treat.

my question is, is the waterpump belt redundent?

because the alternater belt runs the pump aswell...

 

No, because the alternator belt only barely contacts the waterpump pulley. If you were to only run the alt belt, it would slip at high RPM.

 

Yeah, it's made that was so that if any one of your belts snap, you won't overheat and kill the engine. But like Moses said, you can't run on just one belt for long.

 

You can run alt belt only IF you have an electric fan. The glancing-blow-off-of-the-slack-side is plenty to drive the water pump if the water pump isn't driving a fan.

If you have the clutch fan, then the air pump should be considered to be mandatory.

 

thanks guys...

ill go and laugh at him now

 

why is the air pump mandatory if you still have the clutch fan? i havnt been running an air pump since owning my 7, and still run the stock clutch fan.

 

He's saying that the water pump will slip if running only one belt and the clutch fan. So you either need to get a dual alternator pulley or retain the air pump.

Another solution I've seen is to get a a short belt that will just slip over the main pulley and water pump.

 

That's what I have done. Just go to your local parts store and ask for a belt that is 22 inches long. I got mine from NAPA.

 

ahh ok, i have the dual pulley setup.