Squeaking Noise Under My Hood

[40belowceo]

I recently noticed a squeaking noise coming from under my hood. Some days the noise is low on others its very noticeable. One day I turned the car on the noise was extremely loud but went down after a few minutes. When I open the hood and the noise points to one of the main belts on the right side of the engine. I also noticed the sound increases at times when I turn the steering hard left or right.

I have heard this sound before on many cars driving around with it and its quite common. I hear it mostly on working vans and mini vans but I cant have my M driving around with this sound.

Any ideas on what this can be? I want to be prepared and possibly buy the part myself so my mechanic wont try ripping me off. When I went to him without the car he said it might be the "bearing" but have said he will have to look at it. Last time I needed my thermostat and radiator replaced he hit me for $380.

Thanks all,

[elwesso]

Sounds to me like the belt or the tensioner (or both). If he suspects one of the tensioners is bad, I would definitely replace those. If you have a tensioner go out, you are DEFINITELY up a creek without a paddle because the bearings will seize up in the tensioner pulley and usually fry the belt, and then you're definitely getting a tow.

How many miles on the car, and have you ever replaced the belts? If I was doing it, I would buy a complete set of belts and tensioners and then know your good for a long time.

Also, it looks as if the bearings could be pressed out of the existing pulleys, that would save you a little bit of money. I've replaced the bearings in idler pulleys before on my Q45, and it worked great.. The pulley itself is made out of metal so they don't wear out, but the bearings are what fails. I think I was able to get a set of bearings cheaper than one idler pulley.

If you haven't replaced the belts yet, I would try and source the bearings and do everything at once.

BTW, $380 for a radiator and t-stat and the labor to install them doesn't sound unreasonable at all.

[40belowceo]

Sounds to me like the belt or the tensioner (or both). If he suspects one of the tensioners is bad, I would definitely replace those. If you have a tensioner go out, you are DEFINITELY up a creek without a paddle because the bearings will seize up in the tensioner pulley and usually fry the belt, and then you're definitely getting a tow.

How many miles on the car, and have you ever replaced the belts? If I was doing it, I would buy a complete set of belts and tensioners and then know your good for a long time.

Also, it looks as if the bearings could be pressed out of the existing pulleys, that would save you a little bit of money. I've replaced the bearings in idler pulleys before on my Q45, and it worked great.. The pulley itself is made out of metal so they don't wear out, but the bearings are what fails. I think I was able to get a set of bearings cheaper than one idler pulley.

If you haven't replaced the belts yet, I would try and source the bearings and do everything at once.

BTW, $380 for a radiator and t-stat and the labor to install them doesn't sound unreasonable at all.

Thanks Elwesso. How much would a job like this cost for parts and labor. I just recently purchased my M so I dont know much of the history on it. The milage is 115k

[elwesso]

I'm not 100% sure how much parts would be, but I'm estimating labor to be about 2-3 hours especially if you were pressing the bearings out. Looks like the pulleys themselves are about $80 each (there are 2), belts are usually about $20-$30 each (there are 2).. So whatever you're paying per hour plus those parts looks about right. For comparison, a bearing for the idler pulley should be about $10 each, so there's quite a bit of savings. Unfortunately I don't know what the bearing numbers for this car are, and you won't be able to look them up by make/model since they're standard bearings.

Belts are supposed to be changed at 60k miles, so even if they were replaced at 60k miles like they were supposed to (probably best to assume they weren't) you're pretty much due for the next service interval.