Whining noise from engine compartment

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Pedro_Hilario
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Whining noise from engine compartment

Post by Pedro_Hilario »

Hey guys,

I've been having a little problem i hope someone can help diagnose.
For the last few days, everytime i got and start my polo i hear a whining noise coming from the right side of the engine compartment. It only makes that when the engine is cold and in 20 seconds the sound goes away or if I drive a few meters. I'm guessing it's because the engine starts getting warmer that makes the noise go away. But if i speed the revs up a little bit while cold the whining noise will get louder before disapearing.

I got to searching where the noise may be coming and i think it's either the alternator or the cambelt. It's around there, but i cant quite pinpoint it.

I asked a friend and he thinks it's the alternator bearings. I've looked around to see cracks or something like that in the belts and nothing.

Anyone knows what could be causing this? Because i don't want to end up with a broken cambelt (even tough i still have around 10 000 km before the recommended renew of it). Should i get the alternator out and see if thats the cause?



Thanks,

PHG
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

I would first check the alternatorbelt, if that's getting worn out, it needs te be tightened or even replaced (i'd suggest replacement, since it doens't cost much)

If it's the bearings of the alternator, it won't whine, believe me, I had worn bearings in my mk2's alternator, that's a sound as lound you won't call it whining, it's screaming :wink: :evil:
Pedro_Hilario
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Post by Pedro_Hilario »

Thanks,

I was mostly worried about being the cambelt. But i think the sound comes from beneath, where the alternator stands. I'll have that checked.

But since i'm planning on doing the cambelt in february i'll replace the entire set. Hopefully during that I'll get the 3F camshaft into my polo. We'll see.
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

the timingbelt (cambelt) can't whine, since it's "chipped" , meaning it can now slip on the pulley, if this would happen, your valvelift would be out of timing and the would start hitting the pistons quit soon :evil:
Dee-vub
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Post by Dee-vub »

Could be gearbox, or maybe power steering pump??
Pedro_Hilario
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Post by Pedro_Hilario »

JarnoVWPolo6N wrote:the timingbelt (cambelt) can't whine, since it's "chipped" , meaning it can now slip on the pulley, if this would happen, your valvelift would be out of timing and the would start hitting the pistons quit soon :evil:

Humm, having the alternator belt worn will cause this? I didn't quite understand what you meant by that.

i had a look at it today and it seems like its coming from the tensioner next to the alternator. (I'm guessing thats a tensioner, the thing that rolls with the belt on the left of the alternator?)

But what i dont get is why it only does this for 20 seconds, then goes away until the next cold start...!


Can i drive around with this or i should keep it in the garage until i get the whole belts thing done?

Oh and Vee-Dub i dont have power steering and it makes the sound when i rev it up a little while in the cold with no gear engaged. i dont know if that rules out the gearbox....


Thanks
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

Pedro_Hilario wrote:
JarnoVWPolo6N wrote:the timingbelt (cambelt) can't whine, since it's "chipped" , meaning it can now slip on the pulley, if this would happen, your valvelift would be out of timing and the would start hitting the pistons quit soon :evil:

Humm, having the alternator belt worn will cause this? I didn't quite understand what you meant by that.

i had a look at it today and it seems like its coming from the tensioner next to the alternator. (I'm guessing thats a tensioner, the thing that rolls with the belt on the left of the alternator?)

But what i dont get is why it only does this for 20 seconds, then goes away until the next cold start...!


Can i drive around with this or i should keep it in the garage until i get the whole belts thing done?

Oh and Vee-Dub i dont have power steering and it makes the sound when i rev it up a little while in the cold with no gear engaged. i dont know if that rules out the gearbox....


Thanks

Using an online translation device: worn = usado, when you use someting, over time it will start to wear out, or get worn, which means it is slowly losing quality untill it is broke (in this case until your belt snaps/breaks)

Why it only makes that noise when you start it with a cold engine? When the engine is off, the belt doesn't rotate. when you start it, it starts rotating, but due to that it is worn, it slips on the pulley of the alternator and the crankshaft, when it warms up a bit or is forced to make higher rev's (giving some gas) it stops slipping and stops making the sound.

Can't really bother driving some more miles with it, it will only annoy the sh*t out of you :lol: But does need replacement in nearby future, how long depends on how you use eand how many miles you make a day etc.
Pedro_Hilario
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Post by Pedro_Hilario »

Oh, now i get it.

I guess I'll change the alternator belt now and do the timing belt, waterpump and camshaft in february, as planned. Since you say it shouldn't be very costly.

That won't affect the performance of the car right?Doing this first and leaving it for a few months. Because normally people do the entire thing in one go.

I have a second car i can use, so the polo can do very few miles, if necessary. After i get some prices i'll make up my mind.

Thanks for the input
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

Pedro_Hilario wrote:Oh, now i get it.

I guess I'll change the alternator belt now and do the timing belt, waterpump and camshaft in february, as planned. Since you say it shouldn't be very costly.

That won't affect the performance of the car right?Doing this first and leaving it for a few months. Because normally people do the entire thing in one go.

I have a second car i can use, so the polo can do very few miles, if necessary. After i get some prices i'll make up my mind.

Thanks for the input
Haha, no, can't do any harm to the engine, replacing worn parts can only do good :wink: so just get a new one and put it on, job of couple of minutes 8)
warrmr
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Post by warrmr »

JarnoVWPolo6N wrote:
Pedro_Hilario wrote:Oh, now i get it.

I guess I'll change the alternator belt now and do the timing belt, waterpump and camshaft in february, as planned. Since you say it shouldn't be very costly.

That won't affect the performance of the car right?Doing this first and leaving it for a few months. Because normally people do the entire thing in one go.

I have a second car i can use, so the polo can do very few miles, if necessary. After i get some prices i'll make up my mind.

Thanks for the input
Haha, no, can't do any harm to the engine, replacing worn parts can only do good :wink: so just get a new one and put it on, job of couple of minutes 8)



jarno isnt the Auxillery dive belt the one that drive the Water Pump and Power Steering pumps and possibly the oil pump ( im not sure on that one)

so if this belt were to snap or slip off then it will cause the engine to over heat as the water pump will stop and you will also loose power steering at the same time.

if you want a cheaop fix untill you can get it done you could spray some hair spray on the belt or some of that really weak 3m spray clue( tack and stick i think its called. this will stop the belt slipping for a 100 miles or so till you can get it fixed. it depends on how worn it is.
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

warrmr wrote:
JarnoVWPolo6N wrote:
Pedro_Hilario wrote:Oh, now i get it.

I guess I'll change the alternator belt now and do the timing belt, waterpump and camshaft in february, as planned. Since you say it shouldn't be very costly.

That won't affect the performance of the car right?Doing this first and leaving it for a few months. Because normally people do the entire thing in one go.

I have a second car i can use, so the polo can do very few miles, if necessary. After i get some prices i'll make up my mind.

Thanks for the input
Haha, no, can't do any harm to the engine, replacing worn parts can only do good :wink: so just get a new one and put it on, job of couple of minutes 8)



jarno isnt the Auxillery dive belt the one that drive the Water Pump and Power Steering pumps and possibly the oil pump ( im not sure on that one)

so if this belt were to snap or slip off then it will cause the engine to over heat as the water pump will stop and you will also loose power steering at the same time.

if you want a cheaop fix untill you can get it done you could spray some hair spray on the belt or some of that really weak 3m spray clue( tack and stick i think its called. this will stop the belt slipping for a 100 miles or so till you can get it fixed. it depends on how worn it is.
nope, timing/cambelt drives both water- and oilpump, so won't cause the engine to overheat. Yes, powersteeringpump is on same belt as alternator. But when that belt only whines, it still has some life in it, but like a said earlier, just replace it to be sure, sucks getting a snaped belt --> no powersupply for your sparkplugs+injection etc. untill your battery runs out :evil:
Pedro_Hilario
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Post by Pedro_Hilario »

I still need to get some prices on this but i'm considering doing it myself. I'm into that DIY wave, before taking it to the garage. The only thing i wont mess around with is the timingbelt. Unfortunately i'm still don't have the mechanical skills to do that.

I'm going to read about how to do this, and if it turns out it's a couple of minutes job like Jarno said i'll do it over the following weekend.

Thanks for helping out, guys.

PHG
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

How-to change your alternator belt:

-1) the belt is tightened by a spring on the alternator, use for instance a steel pipe or crow-bar as a lever to push the alternator towards the engine, now the belt will come "free"
-2) take the old belt of and put the new one on
-3) now release the pressure on the alternator and let it "swing" back away from the engine, making it tighten the belt again
-4) no go back inside your house, wash your hands and go to UK-polos.net to leave a messege how easy it was :lol:
iggy350
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Post by iggy350 »

haha that seems like a nice quick and easy guide. or you could do what i did, take it for a service and let them do it for u :) altho it did cost a lot imo
JarnoVWPolo6N
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Post by JarnoVWPolo6N »

iggy350 wrote:haha that seems like a nice quick and easy guide. or you could do what i did, take it for a service and let them do it for u :) altho it did cost a lot imo
costed me 10 euro for the mk4 and 12 euro for the mk2 :wink:
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