strange sound

Nizar

Original poster
Member
Dec 7, 2011
65
hello recently i noticed a strange sound when i start the engine in the morning, after 5 mints it goes
what it would be ??:confused:
thank u all :smile:

[video=youtube;cbowAgLAgkg]http://www.youtube.com/watch?v=cbowAgLAgkg&feature=youtu.be[/video]
 

Hypnotoad

Member
Dec 5, 2011
1,584
I'm pretty sure you can even see movement in the fan blades. Maybe it's just the video though.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
I think that amount of runout in the fan blades while running is normal, but you should wiggle them when the engine's off to confirm.

You can listen more closely at the exhaust manifold side, but it may be a crack that closes up when hot. If you restart a hot engine, does it happen or is it quiet? Also could be a idler or tensioner pulley, but they are almost always a lot higher pitched. You can also remove the serpentine belt for a minute and make sure it's something being rotated by the belt, which could also implicate the alternator or AC compressor bearing. I assume you already tried forcing the AC compressor off with the snowflake button?

These sorts of noises would be a perfect problem to troubleshoot with a mechanics stethoscope. Sometimes people use LONG screwdrivers to do the same thing - to transmit noise from a specific area to their ear. Under $20 typically even if you have to buy one - it's cheaper than paying for a mechanic if you insist on a DIY project.

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Nizar

Original poster
Member
Dec 7, 2011
65
the roadie said:
I think that amount of runout in the fan blades while running is normal, but you should wiggle them when the engine's off to confirm.

You can listen more closely at the exhaust manifold side, but it may be a crack that closes up when hot. If you restart a hot engine, does it happen or is it quiet? Also could be a idler or tensioner pulley, but they are almost always a lot higher pitched. You can also remove the serpentine belt for a minute and make sure it's something being rotated by the belt, which could also implicate the alternator or AC compressor bearing. I assume you already tried forcing the AC compressor off with the snowflake button?

These sorts of noises would be a perfect problem to troubleshoot with a mechanics stethoscope. Sometimes people use LONG screwdrivers to do the same thing - to transmit noise from a specific area to their ear. Under $20 typically even if you have to buy one - it's cheaper than paying for a mechanic if you insist on a DIY project.

View attachment 11260

i dont know i think its somewhere around the alternator and yes its just can be heared when the engine is cold just the first 5 mints in the morning another thing but am not sure that there is no relation between the sound and the engine rpm !!
 

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