Just noticed a chirping sound on the left side of the engine. It seems to be a little louder near the back by the oil filter but that could be that it is just a little more open back there. Doesn't sound like anything that is going to fall off tomorrow but doesn't sound normal.

This 204 Cooper S has about 125k. I purchased it in 2010 with 38k on it. I have done most of the typical repairs for a Cooper this age but haven't looked at the belt before. Doesn't see to be any cracks in the belt where I have looked at it but it has alteast 100k on it. Could the chirping noise be one of the pulleys? If I am in there to replace the belt, is there anything else I should do?

Replaced the catalytic converter a few weeks back. Much easier job than I expected. Replaced the oil gaskets when I was in there. Thanks everyone for the recommendations. My P0340 code seems to be be gone for good. Also re did the checkerboard roof decals as they were rough around the edges.

It is looking sharp again.

 

I would replace the belt, idler pulley, and belt tensioner. I had a chirpy noise recently. It turned out to be the pulley on the tensioner. I want to say that I got an idler pulley for $35, tensioner for $80, and belt for $20. At 125k it's reasonable that any or all of those need to be replaced. It's not a hard job, though you either have to loosen the motor mounts and jack the motor up a little, or put the car in front end service mode to get the tensioner out. I'd also take a good look at your crank pulley while you're in there and see how the rubber looks, they all fail eventually.

Is it more noticeable at start up? and/or does it go away after it's run for a while? my bearing noise disappeared after the car had run for a bit.

 

If you have (or know someone who has) a hydraulic press, I’ve always had good luck pressing out the old bearing in an idler pulley and taking it to a bearing supply house and simply replacing the bearing.

I’ve only done it on domestic makes though.

You can usually buy the highest quality bearing available for less than changing the whole pulley.

 

I agree at 125k it would be reasonable to replace those. Thank you for the details and cost estimate. If you are going to go in there, you might as well do it all. I noticed the extra noise a couple of weeks ago but haven't noticed it the sound changes depending on run time and conditions.
To replace the belt, I understand you need a special tool to unload the tensioner?
I put the mini in front end service mode, can I get to the sensor gasket that tends to leak on the front? I also have on my agenda replacing the valve cover gasket.

 

This one. Available a number of places on line including all or most of the vendors on this board.

Don't worry about the price; think of it as an investment, as you'll be using it again.

 

If filter side for 1st Gen that would be RIGHT side not left.

 

If the MINI was purchased used....check the SC pulley and see if its still stock before buying new OEM size belt...

 

Good point I was looking at it with the hood open <grin>

I did purchase the MINI used and it did have several enhancements that were done by DINAN so upgrade of SC pulley is not out of the question. How would I verify before ordering belt?

 

The idler pulley is a likely candidate for "chirping." That's also the least expensive repair (around $35 aftermarket). Go there BEFORE you replace an expensive belt tensioner assembly.

 

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Hi, newbie here. Would you recommend buying an engine jack/hoist to do this job, or just put it in front-end service mode? I don't have a big issue buying some tools because I know I'll need them again, but wanted to know which way is easier to get the job done. If you do recommend buying an engine jack, do you have any that you recommend for the r53? Thanks!

 

I bought a 1.5-ton floor jack from Harbor Freight and it works great on the Mini.
https://www.harborfreight.com/15-ton...ack-64545.html

 

Yeah -.What Chief said.
No need to go nuts with exotic tools just yet. As mentioned; A belt tension release is a must have/indispensable tool.
I'm no ace mechanic and don't mean to sound officious; However just removing the inner right wheel liner, removing the top right engine mount, neg ground wire and lower "dog-bone" engine mount. will allow you to jack up the engine with a floor jack to get sufficient access to the serpentine belt and related pulleys.
A note of advice: Use a block of wood between the jack and under the engine/oil pan.

Just my 2¢.... for what it's worth

 

you definitely don't need an engine hoist for this job, a jack and a block of wood under the oil pan is plenty good. I ended up putting the car in front end service mode rather than lifting the motor a couple of inches, so definitely no engine hoist needed.