Accessories Belt -pulleys or not

[ekkathewrekka]

I have 135i N55 and wanted to do some preventive maintenance as I have a 100000km on it.

Likely suspects are radiator flush, auto transmission flush and filters and accessories belt.

Locally (Oz) it’s about $300 for the tensioner and pulleys For the accessories belt so would prefer not to change. But I do want to change the belt.

Interested in the forums thoughts is this false economy not changing the pulleys, there are no problems, squeaks or concerns.

[dtla1]

I would say no need to change.
Maybe buy a set anyways, especially the tensioner to have on hand if you start hearing some noises, but otherwise, no need.

Prob no need for belt yet either, but wouldn't hurt. More important to keep an eye on Oil Filter Housing Gasket to make sure no leaks onto the belt.

[Olgeezer1]

I'm coming up on the same mileage and thinking also that it's time for a change of belts and pulley/tensioner. The way I look at it is that belt is 10 years old and a failure, though unlikely, can be a very bad thing. For the pulley/tensioner it's a "while you're in there" thing. That tensioner is also 10 years old and if it's something I only have to do every 10 years then I can live with the one-time cost. Our parts costs here in Canada are quite high but looks like you've got it even worse. Still, it's only every 10 years.

[ekkathewrekka]

Thanks guys

[zx10guy]

I did this service myself. On the mileage thing, personally, I'd just get the belt changed. While a small chance, there is a chance if the belt breaks that it could get sucked in through the front main seal. This is a known potential problem with the N54 and N55 engines. While there hasn't been a lot of reported issues where a broken belt did get sucked into the motor, it can happen. If it does and you don't recognize it has happened to shut down the motor immediately, you're looking at a whole new motor.

I personally know of one person with a N54 motor that this has happened to. Luckily he recognized the belt had snapped immediately and shut down the engine immediately. Ended up saving his motor.

On the pulleys and tensioner, yes it's more or less a while you're in there thing. Even though I didn't notice any weird noises, observed any abnormal vibration/movement, I decided to replace all of mine. To me it's not worth the headache of having to go back in there again to replace those items.

[MightyMouseTech]

Do it right, and replace everything.