my early 85 is making an intermittent whirring sound. particularly noticable at idle.Ussually noticable after warmup. If I bring the rpm up a little bit then let it settle to idle it sometimes stops.If you have ever heard a sprint car supercharger - that's what it sounds like... kind of a rring..rring. rring sound. HELP Water pump? Belt?

 

It could be Irritable Bowel Syndrome. How often do you move your bowels? I'm good friends with a gastroenterologist, and he's having a Christmas sigmoid endoscopy special.

 

sounds to me like SARS

 

whirring c'est parfaitement naturelle!

 

Could it possibly be the cooling fans? If you have the older style 3-blade fans, they're particularly loud / noticeable. This is normal.

 

Cooling fans sounds like a good tip. Check if the sound starts when your engine temp is high.

 

I'd be looking at the balance shaft idler pully as well. Your description sounds exactly like a mis adjusted pulley. Don't worry, its an easy and cheap fix if thats it.

Regards,

 

That sound may also be from the balance shaft belts that are tensioned too tightly. Manual recommends 2.7 for the balance shaft belt, which is quite loose in reality. SOme mechanics like putting it on ~3.5+ for safety..........

 

Mine's always made a whine, but it seemd constant at idle, would go away at higher RPM.

I would check the tension, and if that's good, than not really worrya bout it. If you haven't changed your belts, rollers, or waterpump in a while, I would suggest it. It could be waterpump on its way out.

 

If a so-called "mechanic" is tensioning the balance shafts to 3.5, I'd rap them upside the skull with a crescent wrench. Tensioning the belt tighter than factory spec will NOT help and can in fact break things with catastrophic results. As the engine heats up, things expand and the already too-tight belt can run the risk of snapping. If it does, you can almost bet that shards of it will mess with the cam belt and if THAT happens, you just bought eight (or sixteen) new valves, possible head machining, possible piston replacement, possible BLOCK resurfacing / boring or replacement due to busted valve fragments scoring cylinder walls, etc, etc, etc. DO NOT OVER TENSION YOUR BELTS!!!

Let me say that again:

DO NOT OVER TENSION YOUR BELTS!!!

Is that clear enough?

Tell that "mechanic" he / she is an idiot and take your business elsewhere. Or better yet, do it yourself.