1985 190E loud squealing sound and smoke from my belt
 

I just had the belt tensioner replaced a few weeks ago. The belt is tight.
when i turn the car on i get a loud squealing sound and smoke from my belt.
It started this morning out of nowhere as i was pulling into a parking lot. i havent moved the car since. Any ideas what could be the problems, and any solutions?
Thanks.

It sounds like a tensioner may have frozen up on you. It could be the air pump locked up too. You will have to check the different things the belt drives to try and find the problem & maybe loosen the belt some in order to do it.

thanks, i'll go check it out right now.
Not to sure about where to find the air pump.

If you have the 2.6L you may have to remove the fan clutch up front to be able to see what the problem is. It's pretty well covered up on that model. Since it happened so soon after replacing the tensioner, it can possibly be the suspect here.

No air pump in 1985.

hmmm... could your alternator pulley old and maybe starting to lock up...\

or another pulley where the bearings are going