Screaming noise on ignition

[chis101]

Bought a car a last month and was getting an annoying engine rattle. I took it back to the dealer under warranty who replaced the alternator belt. Problem solved!

Since then though, intermittently, on ignition there is a short, loud screaming noise which sounds like it could be the belt slipping. I took it back again and the mechanic tightened it for me on thursday but today i noticed the problem persists.
Is there a settling in period for something like this or should I be getting back on to the dealer?

It's a Mitsubishi Colt by the way.

[Zoobeef]

Souds like its still slipping. I'd take it back to them and if they cant get it to stop then they should maybe try a different belt

[chis101]

Cheers, I'll do theat.

They will be sick of the sight of me...

[Pumaracing]

If a belt has been slipping for long enough it may have worn the groove in the pulley out so wide the belt bottoms out in the groove. It will then always slip until a new pulley is fitted so the belt grips on its edges as it's designed to do.

[Pushrod-Power]

Its probably fitted with the Serp drive belt system and the mechanic is not tensioning correctly seen this more times than I care to remember