What's this noise?

dpgx5 · #1 11-12-2013, 07:10 PM

Hello Forum!

On start up this AM, I started hearing this noise and took a little video.
X5 - YouTube

Is it the belt that needs to be replaced? idle pulley? or something else.

Cheers,
N

KyleNatolix5 · #2 11-12-2013, 11:03 PM

Does this noise go away after a few seconds? I have a sound similar to this I have to get around to figuring out.

admranger · #3 11-13-2013, 01:53 AM

It might be the belt or idler pulleys. Easy check.

Mark the direction the belt turns on the car (use a sharpie or something like that). Take the belt off. If the idler or tensioner pulleys spin with little or no resistance, they are done.

However, you may just want to try a little trick that I found is useful in determining if it is the belt first. Spray belt dressing on the belt. If the noise goes away, it's the belt. Some belts get noisy after a while.

Only other thing I can think of is the crankcase vents are torn or not sealing well when cold. But it sounds too cyclical to be them (those my ears aren't fully calibrated -- seek professional advice on this one).

dpgx5 · #4 11-13-2013, 12:34 PM

Thanks Adam.

Will do a check and try the spray first.. easiest.
Then the rest will follow.
Re; CCV - I just ordered some of the repair kit and I will also change those for piece of mind.

Cheers!

Quote:

Originally Posted by admranger

It might be the belt or idler pulleys. Easy check.

Mark the direction the belt turns on the car (use a sharpie or something like that). Take the belt off. If the idler or tensioner pulleys spin with little or no resistance, they are done.

However, you may just want to try a little trick that I found is useful in determining if it is the belt first. Spray belt dressing on the belt. If the noise goes away, it's the belt. Some belts get noisy after a while.

Only other thing I can think of is the crankcase vents are torn or not sealing well when cold. But it sounds too cyclical to be them (those my ears aren't fully calibrated -- seek professional advice on this one).

dpgx5 · #5 11-14-2013, 01:09 PM

I sprayed some belt dressing and the noise got louder? will that mean its the others?
Belt is original.

bcredliner · #6 11-14-2013, 01:31 PM

Doesn't sound like a belt to me, sounds more like one of the pulleys is bad. In my experience with the belt is removed a good pulley will also be quiet when you spin it by hand, a bad pulley will be loud, you can hear the bearings 'rattling'.

I don't think the belts have been eliminated. Usually a bad belt will have cracks on the side toward the pulleys and likely feel loose, having stretched. To much belt dressing will cause the belt to slip more for a little while but it should quiet down if the belt is good. If you remove the belts to check pulleys be sure to check the water pump and alternator pulleys'.

Does the sound go away or change after you get to operating temp?

Does it get louder when you turn the steering wheel from lock to lock?

dpgx5 · #7 11-14-2013, 09:21 PM

Quote:

Originally Posted by bcredliner

Does the sound go away or change after you get to operating temp?

Yes, the sound did go away/quieter when I got home from work.

RealOEM.com * Diagram Selection

Should I get the water pump and alternator pulley?
Change both while I am there for piece of mind?
Would the tensioner be another to replace?
Thank you.

dpbayly · #8 11-14-2013, 04:08 PM

Ive heard a noise very similar to that before and against my advise the chap carried on driving it and a day later his water pump with the viscous fan on it let go on the motorway and took out his radiator, radiator shroud a couple of coolant hoses as well as the tensioner and it also dented the hell out of the bonnet from under side.

So don't be tempted to delay finding the cause, I'd whip the belt off and give the water pump pulley and good wiggle and spin

bcredliner · #9 11-15-2013, 12:53 PM

Quote:

Originally Posted by dpbayly

Ive heard a noise very similar to that before and against my advise the chap carried on driving it and a day later his water pump with the viscous fan on it let go on the motorway and took out his radiator, radiator shroud a couple of coolant hoses as well as the tensioner and it also dented the hell out of the bonnet from under side.

So don't be tempted to delay finding the cause, I'd whip the belt off and give the water pump pulley and good wiggle and spin

Make sure to tell that guy not to be outside when there is lightning.

What do you think the odds are of that happening? Was that a X5?

dpbayly · #10 11-15-2013, 04:55 PM

Quote:

Originally Posted by bcredliner

Make sure to tell that guy not to be outside when there is lightning.

What do you think the odds are of that happening? Was that a X5?

Not an X5 it was an unloved 540i same engine and he never had much luck when it came to cars.