Hi guys,

Let me be honest, I've been through 3 fan belts and a brand new replacement tensioner in order to eradicate the constant chirping noise from under the bonnet. Sadly today is the day the noise has returned.

The chirping noise is constantly there, it doesn't get louder (on start up for example), it's a constant chirp that only quickens when increasing the revs of the engine but above a certain RPM the noise disappears. I guess the engine noise becomes louder than the chirp.

- Is this a case of pulley misalignment?

- Contamination of the pulleys? I did clean them last time the belt was off. I also, by hand individually spun the pulleys (except for the harmonic balancer of course) with no noise heard.

The noise is just a constant chirp that doesn't seem to go away and is probably more audible inside the car strangely. I do know that it is linked to the belt, so it's not the blower motor for example.

Any help appreciated,

Matt.

Alternator bearing?
Tried spinning the alternator with the belt removed. Should turn easy & smooth. Sticky spot when turning means bearing problem.

A few details more might help.

Engine? Are we talking 1.2, or the TA or diesel?

For this I'm assuming 1.2.
You've apparently determined that the chirp is from the front end of the engine and are sure it is the alternator belt. But replacement has not effected a cure, so we have to consider the belt being an effect rather than the cause.

Aircon, or not?

With aircon, the tensioner is sprung and automatic, so should maintain tension. Would not expect chirps from an aircon car.
Non-aircon, I believe the tensioning is it effected by moving the alternator, so your description suggests an aircon car. How am I doing so far?

It is unlikely that belt alignment would alter, but checking should be easy, just look down on it and see if it lines up between the pulleys nicely, or if it seems to fight as it goes onto any pulley.

With aircon, the aircon pump will kick in and out when the pump is needed. As the electromagnetic clutch engages, there is a high current requirement. If the aircon pump is trying to seize, this may cause a chirp as the belt momentarily slips before the pump turns. To check this, with engine running, aircon switched on, set to a low temp to make it work, and from under the bonnet watch and listen as the pump engages.

With aircon off, the freewheeling electromagnetic clutch might be trying to seize, so that might be the source of the noise.

The aircon electrical demand may also cause the alternator to to cough. But a properly tensioned belt should not do this.

The alternator itself could be about to die. Bearings in either end could be worn or about to seize, which may cause the noise you are hearing.

And in behind all this is the cambelt tensioner. These can chirp when trying to die. Is a belt change due, has it recently been done? Was a new tensioner included last time.

Hope this helps. If not a 1.2, give more detail.

run the car for a few seconds without the belt on and see if the noise stops. if you have changed the belt and tensioner and cleaned everything, then i would suspect it is one of the ancillary items that is being driven by the belt. most likely alternator.

Hi,

Sorry for not giving more information. The car is a 1.2 60bhp Eleganza with climate control and automatic tensioner.

Strangely enough, the drive belt did not chirp for the first 10 seconds when the car was started. I've only ever come across drive belts that chirp or squeak from cold, but this is the other way around, noisy when warm. But as I say the noise kicks in after 5-10 seconds.

The battery is charging fine and the alternator output is good. It's just the chirping noise that's annoying. Especially having been through 3 belts and a tensioner!

1st belt - a Dayco which chirped
2nd belt - a genuine FIAT belt which was quiet for a few months
3rd belt - a bosch belt with a material backing as I thought the belt was slipping on the tensioner.

I had the cambelt and tensioner both replaced in 2015.

Matt.

Does a failing water pump bearing cause a chirp noise on these engines?

I've had cam belt tensioners chirp, chatter or whirr in the past.
(you'll hear it if you run it up the aux belt is disconnected)

And I've had rubber dampers in crank pulleys of other cars start to break down and cause the belt to twang the tensioner so that chatters and squeeks as well, though not sure if the 1.2's pulleys are dampered.

I think it's 100% aux belt related. I could be the tensioner, it could be one of the pulleys or misalignment.

One thing I have noticed though is some people say it's a characteristic and something that should be lived with. I'm not settling for that though, it stopped chirping for a while when the belt was replaced, so something is faulty.

I think I'll take the belt off and give everything a check as this time it might not be the belt, it could be the alternator this time, who knows?

Matt.

I dont know if you tried this (read your thread a few hours back) but my first thing would be to put wd 40 on the belt, if the squeel goes away its the belt, then try each component - its not a permanent solution, but it helps troubleshooting without using a wrench

To test that I'd rather spray some water. Rubber and WD40 is not a good combination.

gr J

You could get belt-liquids as well, my thought is if its squeeling its on its way out anyway, if I take it off at some point Ill swap for new since its so cheap anyway, but wd40 is easily appliable with the spraynossle... I have a belt squeeling a year on after I wd40'ed to verify where the squeel came from... I have a new belt sitting in case it snaps, but cant be bothered to lift the car and take off the wheel just because of a squeel... but sure water might be fine (just dont get tapwater in electrics)

FFS do not put a lubricant like WD40 onto the belt. The belt drives using friction, lubricating it will make the problem worse, and may take a very long time to wear off. Water at least will dry out quickly.

Now we know it has aircon. Turn the aircon OFF. Now try it. The chirp shortly after startup suggests this is when the aircon pump engages. If the alternator was trying to seize, I would expect the chirp to be immediately on startup.

Hi,

This morning, I jumped into the car, started the engine and the rhythmic chirping began and once the engine settled down to idle speed (once warm) the noise went away.

So I put the air con on to see if the noise came back, no noise. Then I decided to put strain on the alternator, all lights, heated window and it was still quiet.

So the belt slips now and again and not always from cold.

Are you absolutely sure the belt slips? The noise could be nothing to do with the belt, just in that area.

The noise goes away as the engine warms up. Could be something internal not being lubricated as it expects? Has anything been done to the engine recently? Is it due an oil change? Might be worth taking the cam cover off and checking it is all as oily as it should be.

Cambelt tensioner can be noisy but settle when warm, usually a sign of impending doom. Although not too bad on the 60hp, as no engine damage occurs.

this was a toyota, but i had an intermittent squeaking noise. it mostly related to the temperature/humidty outside as sometimes it wouldnt do it. i replaced everything and then gave in and replaced the waterpump, that was the issue in the end. it took me 2 years of faffing about to find it.

you could spunk a bit of wd40 on the waterpump shaft, behind the pulley and also a bit in the leakage hole (if it has one). i would only do this if you suspect that it is the waterpump.

i have also had some random squeaks from the alternator when the bearing got dry. on a dry day it would squeak a bit. again, temp fix is some wd40 in the bearings to soften up the dry grease. this bought me some time to get some new alternator bearings.

Hi guys,

The noise seems have gone away for now. I changed the oil and engine filter myself about 2 weeks ago and all is well regarding that.

I bet it probably is the water pump, even though it and the cam belt (with tensioner) were replaced back in 2015. Funnily enough, the engine was chirping around that time too.

I remember taking it back to them a day later for them to say everything was fine and that these engines being old tech can be quite noisy.

Matt.

Alternators can corrode internally. The winding cores expand and eventually crack the casing causing the rotor and stator to rub. Noise is generally worse when cold as the stator expands when warm. Eventually the thing will seize solid.

Get an inspection mirror and look around the whole casing. Any cracks are a bad sign.

Hi

I guess with the alternator being fitted below the windscreen scuttle drain, it's not located in the best place from the elements. I think the Punto has the same problem too.

Matt.

Hi,

The noise always get worse when the engine has got up to temperature and has been on the motorway for at least 30 minutes. And I thought I'd capture the noise on video for you all to hear.



Your help is always appreciated.

Matt.

Update,

Took the aux belt off the Panda and spun each pulley and found the alternator pulley to be the culprit.

I've seen loads of videos on stripping the alternator and replacing the bearing, but chances are being a 2009 car, the alternator would die shortly after. So I ordered a new one and it's due on Tuesday.

I've never heard of the manufacturer before - RTX alternators but I'm hoping it'll be up to the job.

Matt.