Air Con question - help required please

Hi all

Hope this is in the right section.

My air con has started to make a noise when I put it on - it sounds like a belt slipping or bearing going....hard to tell which. It tends not to do it if the vehicle is stationary, but when the engine is under load, there is an audible squeal from the dashboard when the unit is turned on e.g. if i trun it one when driving above 40mph. It then goes, but when the engine is under load, it returns sometimes e.g. when going up a hill or overtaking.

My initial thought was the drive belt (assuming the air-con is belt driven?), but the noise is from the dash rather than the engine....so I wondered if it was a fan bearing or similar?

Having just spent a load of cash on the MOT, this is the last thing I needed, so I'm hoping that one of the experts can point me in the right direction for diagnosis and hopeful fixing.

Thanks very much

Nick

I had this, it was the belt and was only cured by a new belt.

New belt and the correct tension!

If yours is a 2.8ltr 3L engine , like mine, the adjuster is got at by removing the underseat section - drivers side. 14mm socket to get the seat & seat belt anchors, 12mm for the offside inspection hatch. The adjuster is down near the offside rear of the radiator. !4 mm - undo the idle pulley then 14mm for the adjuster. Sometimes needs a tap to release the belt tension.
On mine I found that sometimes the idler pulley near the Air Con unit screams a bit if the bearing lacks lubrication. Also if the tension is wrong (loose) it rotates after the engine is turned off.
I think the noise "from the dash" is actually the belt slipping, it is a very long belt that goes round the crank pulley, over the adjuster pulley, over the air-con unit then over the idler pulley.
Takes about an hour to change - don't know what the belt cost is currently.
Good Luck!!

In my case the correct tension made no improvement and it started squealing once more in a matter of hours, I think the belt becomes glazed. As i said probably a new belt needed.

Wasn't there something you could spray on the belt to 'lubricate' it without making it slip? I had some ( years ago ) and seem to remember it worked well.

thanks very much for taking the time to reply- very much appreciated

i'll have look at the weekend

incidenlty - in case it needs the belt, did anyone have the parts number, by any chance please

thanks very much

nick

I had a similar problem on my old petrol hiace but the sound wasn't from the dash, it sounded like the motor had done a bearing. My mechanic sprayed some spray lube on the belt and that did the trick.