Technical Whirring Noise.

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Technical Whirring Noise.

So your thinking it's a faulty alternator?
You just told us that with the fan (aux) belt removed it doesn't make the noise? and earlier in the thread you told us it doesn't have air con? - So it won't have a tensioner bearing (which might be a source of the noise on air con versions) It's got to be the Alternator. You'll probably be able to hear the noise by, with the belt off, spinning the alternator drive pulley as fast as you can with your fingers. Probably the garage has refitted the belt by now though? In which case you could try listening to the front of the alternator casing with a "Listening Stick" but, as you have no experience of doing this I'd advise extreme caution because there's serious risk involved from the moving parts.
 
You just told us that with the fan (aux) belt removed it doesn't make the noise? and earlier in the thread you told us it doesn't have air con? - So it won't have a tensioner bearing (which might be a source of the noise on air con versions) It's got to be the Alternator. You'll probably be able to hear the noise by, with the belt off, spinning the alternator drive pulley as fast as you can with your fingers. Probably the garage has refitted the belt by now though? In which case you could try listening to the front of the alternator casing with a "Listening Stick" but, as you have no experience of doing this I'd advise extreme caution because there's serious risk involved from the moving parts.
So when I take the belt off. Am I still able to use the clutch and rev the engine a little bit?

Obviously can't change gears whilst the car is stationary.
 
So when I take the belt off. Am I still able to use the clutch and rev the engine a little bit?

Obviously can't change gears whilst the car is stationary.
Taking the fan (aux) belt off will just stop the alternator charging the battery. The important water pump on these, and many other engines, is driven by the cam belt so will continue to work. You could drive the car until the battery voltage dropped low enough the plugs wouldn't fire if you wanted to. Do take the belt right off though, if you just slacken it but don't completely remove it then it might get tangled up in the pulleys.
 
Taking the fan (aux) belt off will just stop the alternator charging the battery. The important water pump on these, and many other engines, is driven by the cam belt so will continue to work. You could drive the car until the battery voltage dropped low enough the plugs wouldn't fire if you wanted to. Do take the belt right off though, if you just slacken it but don't completely remove it then it might get tangled up in the pulleys.
So I can drive the car normally with the fan belt off? How much drain on the battery will it do without the belt on?
 
So I can drive the car normally with the fan belt off? How much drain on the battery will it do without the belt on?
Depends on how good the battery is and what other loads you have switched on ie. lights, heater fan, rear screen, etc, etc. With a good and well charged battery and no "auxiliaries" switched on, you might be able to drive for hours. It's a bit of a difficult question to answer. Expect the ignition warning light to come on and she just might light up the check engine light too, which, if it happens, will probably need to be switched off using a scanner/code reader. She might just light up the ign warning light only though. If she does light up the CEL she might (but I'm not sure) turn it off again by herself after a certain number of restarts with the fan belt reinstalled? Anyone know? some cars will do this.
 
Depends on how good the battery is and what other loads you have switched on ie. lights, heater fan, rear screen, etc, etc. With a good and well charged battery and no "auxiliaries" switched on, you might be able to drive for hours. It's a bit of a difficult question to answer. Expect the ignition warning light to come on and she just might light up the check engine light too, which, if it happens, will probably need to be switched off using a scanner/code reader. She might just light up the ign warning light only though. If she does light up the CEL she might (but I'm not sure) turn it off again by herself after a certain number of restarts with the fan belt reinstalled? Anyone know? some cars will do this.
So I went to my mechanic friend today, and even with the belt off it makes the same noise. He asked his friend in the garage next door for an opinion too and definitely said it sounds like a Cambelt problem :(
 

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So I went to my mechanic friend today, and even with the belt off it makes the same noise. He asked his friend in the garage next door for an opinion too and definitely said it sounds like a Cambelt problem :(
@Adam1984 I think you have confused the issue by earlier saying the noise went away when you removed the auxiliary belt whereas the two videos you posted above seem to pretty clearly indicate the engine makes the same rotational whirring sound with the belt removed.

I don't have the 1.2 cam belt engine but that does sound like something is not entirely happy, be it tensioner or water pump. Is it possible to over tension the belt on this engine or is the tensioner a straight forward spring loaded job? Someone with the engine will know.
 
@Adam1984 I think you have confused the issue by earlier saying the noise went away when you removed the auxiliary belt whereas the two videos you posted above seem to pretty clearly indicate the engine makes the same rotational whirring sound with the belt removed.

I don't have the 1.2 cam belt engine but that does sound like something is not entirely happy, be it tensioner or water pump. Is it possible to over tension the belt on this engine or is the tensioner a straight forward spring loaded job? Someone with the engine will know.
Yup, there's been conflicting info given here. I don't "blame" Adam, he's a victim of his own inexperience. The last videos he posted make it very obvious it's got to be "findeable". I'm guessing idler, but could be water pump. Belt guards off and go looking with a listening stick if it was me.

The idler on the 2012 onward is a normal spring loaded job. You could over tension it when fitting it but it would need to be someone pretty thick as it's got indicators which line up when properly tensioned.
 
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