[Ozzy93]

Hi All,

My serpentine Belt Disintegrated whilst driving, has anyone experinced this on the M2's?
Seems to be a known issue with the N55 engines.

My M2 has modifcations so i did not bother going down the warranty route, so i bought a belt from the dealers for £35 and fitted it my self. (Big mistake)

Could i have caused any internal damage?
I read that parts of rubber from the belt could have got into the engine.
As a result i am Sh**ng my pants, the last thing i want is a blown engine.

I have done 300 miles and there are no oil/coolant, issues, yet.

Thanks in advance.

M2 2018 LCI Auto

[chmura]

Watch this video. Yes you could have internal damage. Do you have any oil leaks? Usually oil leaks from the filter housing will cause the belt to break and it breaks the seal from the crank hub and pieces of belt material can get inside the crank case. There is an oil pump in the crank case and it can become clogged.

Make sure the crank oil seal is intact before putting on a new belt.

[Drop the hammer]

My belt blew up on my n55 m2. Was leaking oil all over from the front pulley. Belt cords were wrapped around crank pulley and damaged the seal causing the leak. Warranty covered mine but it was a big job as have to remove the sub frame to remove oil pan to clean out debris and then reseal the engine crank seal. All runs good since the replacement. I did shut car off as soon as the belt blew (was very loud when it happened). I lost very little oil but it did make a fine spray of oil mist around via crank pulley distribution and made a mess under there by the time I got pulled over and shut it off.
Anyways if it isn’t leaking and you can’t see any cords around the pulley I wouldn’t worry about it too much. When belt failed were cords wrapped around pulley? Or was belt in a couple pieces and all pieces accountable?

[dvas]

This happened to me a few years ago on my 135i. I had noticed that there was oil pooling up on the oil filter housing due to a leaking gasket, $40 part and a couple of hours to replace. I had scheduled an appointment to have this addressed, but in the meantime drove the car. Because the oil filter housing sits right above the serpentine belt, oil dripped onto the belt causing it to slip off the pulley and become shredded. There was some minor damage to the fan and some hoses, but the greatest fear was that parts of the shredded belt could get inside the engine through the main seal. Luckily, this didn't seam to happen as I drove the car for another few years after this happened. But I had to pay for towing and was ultimately out about 4 x as much money to get it all fixed.

I did not know this was also an issue with M2 N55. Nevertheless, I have been trained to keep an eye out for oil leaks and get them addressed immediately. Have not noticed any leaks on my M2, nor does she ever require having to have oil added in between oil changes, thankfully.

What mileage did you have on this car when it happened and did you notice any oil leaks before that could have caused the belt to slip? I would check for damage to radiators, hoses, and fan. Also, check to make sure there are no remnants of the belt remaining that could be pulled into the front main seal. Also check for leaks at the seal.

[Ozzy93]

Thanks All.

A new belt has already been put on. To be honest i did not check if the seal on the crank has split.

I have done 300+ Miles and there is no drop in oil (measuing via I drive)

Its probably worth me having a look around the oil housing to check for leaks.

Will try getting some pictures up this weekend.

[Vallaha]

I'm new to this bare with me. I bought a 2016 M235i last July, had the 50K check up done. They only filled some of the fluids and it was good. With much reviewing and asking advice about getting extended warranty since it ran out after 50k, I decided not to get it. It now has 52k and my serpentine belt shredded, had a Mobile mechanic replace it and drove it for almost a week approx 100 miles, it at times it would idle real low almost to the point of cutting off but it never did. It then gave an error: very low oil pressure. Thats when I took to a trusted mechanic and found out there are peices all the way up to the oil cap. It still sounds fine when running. My question is: can I ever trust even the best mechanic to clean it and have a guarantee or is it basically from here on going to be a money pit... my last question is: with having my 50k maintenance done could that had some signs of wear and tear to it that the dealership should catch. I thought that these belts are only good for about 50k. How is this an acceptable defect by a reputable car makers? Thank you