Hello everyone! Can someone help me?

[Brigand]

Hello, everyone,
I'm new at the forum, and I must say I'm glad there was such place where you can meet people who can, and want to help. That's why I'd like to thank you all in advance, and I hope that i can learn some useful stuff here, and if can, i`ll help (as much as I can). This is fantastic place.
This is my first post, and already, i have a question for you guys.

I bought six months ago, a BMW 525d, e39 2002, Manual, sedan. The car was in perfect condition. Imported from Germany and maintained to the max. The engine, the interior and body, everything in perfect condition. I inspected the car very thoroughly and did a test ride..., not one strange sound in engine, not one in transmission, and not one in suspension, all in all the car was great. (what especially intrigued me, was quiet, nice and steady sound of 6 cylinder engine, that he'd been so quiet, that even some peoples asked me "is that a gasoline engine".. haha

Namely 15 days ago, I noticed, some vibrations on the engine cover, plastics, and cabin filter housings. The vibration was somewhat loud, weird, secluded and show up only when the car was cold, it wasn't steady and appeared at random intervals.
I immediately suspected that the vibration dampener (harmonic balancer) should be replaced and I replaced it with the new one. Loud vibrations disappeared and could only be heard only after minute or two after i started the engine and last only for 10 seconds and then disappear completely. But again, I was not satisfied how the engine works because I noticed another sound, (it's pretty quiet, but it's constant) and it seems to me, that it comes from the rear part of the engine (at the point where the engine is connected to the transmission), but I'm not sure again, I also notice when I'm in the car and when i test shifter, engaging in first speed without the clutch pressed, the sound changes slightly, also, when I drive, and when I press the clutch, I hear some quiet "rotating sound" ..In all likelihood, I think the flywheel is cause, or maybe a whole clutch with a flywheel.

What is your opinion?

Can these two types of vibrations be connected? What do you think?

(Thank you guys in advance!)

[JimLev]

Welcome to the forum.
No E39 diesel engines on this side of the pond.
Your clutch noise could be the throw out bearing.
We have a number of UK and European members that have diesels, hopefully one of them will chime in.

[philly98540]

Welcome to board. Post up a video of noise. That may spark something.

[geargrinder]

I'm with Jim - the on/off w/ the clutch rotating sound under the car etc. sounds like clutch throw-out (also called release) bearing. Sometimes they are noisy only when loaded (push pedal in), sometimes they are only noisy when unloaded (pedal out).

The other noise.. sounds like there's still a problem. Starts after 1-2 minutes then goes away after 10 seconds or so... Sounds like something loose where temperature and sympathetic vibrations / resonance just make it rattle for a short time. Unless there's some function on the diesel motor that activates like an air pump or something? I know ZERO about BMW diesels like Jim says tho'!

[Brigand]

Yes; I also doubt on the clutch release bearing, and most likely it is (cause of noise when i engage clutch pedal), but I doubt that there are still some problems with the clutch set and flywheel.

As for the vibrating sound that occurs when the car is cold; Is there a chance that a "bad shape" of serpentine belt tensioner can cause vibration that is further transferred to rest of the engine? (when I was changing harmonic balancer I noticed that one of the serpentine belt tensioner is in somewhat bad shape)

And can you tell me, how to make sure that the problem is in the whole clutch set and flywheel... whether there is a specific test and check that i can do, and how you do it?

[geargrinder]

As for the vibrating sound that occurs when the car is cold; Is there a chance that a "bad shape" of serpentine belt tensioner can cause vibration that is further transferred to rest of the engine?

Could be. They usually are more likely to make sound than a heavy vibe, but they can be noisy when cold then quite down as they warm up if they are starting to go. My wifes car just had that in fact. Silent as a lamb on cold start now...