engine knocking noise when idling

Hello everyone I'm new to the site and I own a 2006 freelander td4 hse auto . It has just developed a knocking noise which gets louder when heaters are put on but goes off when revved up.both belts were worn so replaced but noise is around crankshaft pulley. does this pulley wear and is this a common fault as it seams to wobble when revved up also. does it have some sort of damper effect. thanks Paul.

Yes - its a common fault that they delaminate and need replacing.

Sounds like its your bottom pulley. If you shine a torch on it you should see some fairy dust/glitter in the area.

is it ok to use for a couple of days till replacement arrives

I wouldn't like to say - if you can actually see it wobbling - then its in a very bad way!

I wouldn't drive it. If the pulley detaches completely. It could cause damage and leave you without drive to the water pump, power steering and alternator.