I have got a belt squeal problem I think.

2005 MCS
28k miles
no mods.

I sprayed some CRC Belt Conditioner on the belt, actually made it worse now. The squeal is worst at cold startup but also squeals when accelerating now that I sprayed it.

It used to only squeal at cold start before I sprayed it. Would go away after warming up.

Question is, will a belt change fix it? Or could it be the tensioner. I can see one full hole on my tensioner.

 

You dont use belt conditioner on modern serpentine belts... Replace the belt and see what happens.

 

It is probably a bad belt, but it may also be a bad tensioner or idler puley.

 

What is the going rate for a belt replacement? My '04 is beginning to squeal.

 

Belt is around $20-40 bucks depending if OEM or aftermarket. BMW Special Belt tensioner tool $75. Labor free if you do it yourself. I would expect no more than one hour of labor at repair shop plus the part.

 

I had the belt replaced on my Cooper S last summer for less than $100 total at an independent BMW specialist. Fixed the squealing issue for good.

 

If you are still useing the belt you car came with, and it is now 3+ years old, the belt is due to be changed....it wears from use, and from age, heat, temp, ozone, etc. If it breaks can cause some very $$$ dammage, and if you are luckey, only leave you stranded on the side of the road.
IMO I would change it as preventive matainance, even if the miles are low.

 

What is this "BMW Special Belt Tensioning Tool"? Is it necessary to change the belt? Mine is making noise now and I need to get under there to change it. I've changed belts in numerous other cars and never needed any special tools.

 

You can check the vendors websites to see the tool. The belt on the "S" is run at very high tension due to the fact it runs the supercharger...and it "consumes" quite a bit of HP. It is possible to do it without the tool.....but IMO ill advised.

I got mine here...
http://www.outmotoring.com/mini-coop...oner_tool.html

The amount of preassure you need to exert on the handle is huge....hense the reason for the long handle. There are a few good DIY's if you search.
If you do the belt change yourself....be careful which belt you get. The belts that the local parts stores will tell you you need is way too long, and will slip resulting in HP loss.... go to the store with the number in hand, or order it with your tool.
You don't actually get under the car to change the belt....just jack it up, remove the passenger side tire and wheel liner, and you have enough access. The first time, give yourself an hour or so....after that it is maybe 30 min or so!! Great way to save money.

One tip...if you bought you car used, check to see if your car has an aftermarket pulley.....the reduction amount is usually marked on the side. Then use this info to determine the belt you need....most vendors will help you, or just do a search. IMO if you have a 17% or a 19%, then replace the belt yearly....15% every 2 years, stock is OK for 3 years...about 30,000+ miles or so. It is much cheaper to replace the belt, than fix several hundred dollars worth of dammage which is common if the belt breaks (can be 1500+ if the car overheats and needs a head gasket!!).