Weeeee noise. Only sometimes, when starting

[FordyStyle]

Hi all fellows!

This is my first thread and I'm glad to join your community. I'd like to share experiences with you about Ford cars and in particular my old Ford Fiesta, that I call my "baby"

Well, let's go to the point: this noise is driving me crazy (uploaded to google drive)!

It deals with my 2001 Fiesta MK4 1.25 16V gasoline.
It started on last January for the first and lasted only 3-4 days and then stopped, then it appeared again a couple of months ago for 2-3 days and stopped and last time it appeared last week.
It's a sort of weeeeee and it happens only when I start my car and for the first 10-15 minutes then stops and it's louder when accelerating. I guess it comes from the right part of the hood and in my car there's the timing belt and the auxiliary belt in that area therefore my bet it's caused by a faulty pulley, but wich one?

I've already tried to put off auxiliary belt to make some pulleys to spin by my hands and hear:
- A/C pulley spins very well and doesn't make any noise;
- idler pulley spin very well but it make this strange noise and I don't know if it's normal;
- alternator's pulley spins quite good and doesn't make any noise to my hear.

I'd like to ask you if you've ever experienced a sort of noise like mine and anyway if you can help me to identify what's its cause.
Thanks in advance

 

[Handy Andy]

Usually a "squeal" noise on acceleration usually means a sticky bearing, so by your troubleshooting - it looks like your Water pump bearing has gone out. The spindle goes into a cavity in the motor and the impeller on the shaft, turns, if the bearings are worn, the spindle and shaft tilt, which can jam the impeller agaisnt the cavity - making it stall and you hear a squeal from the belt dragging itself across the pulley until it can release and start to spin again.

Might also indicate time to change the serpentine belt and the timing belt too...

 

[FordyStyle]

Thanks for your contribution, indeed there're many parts involved with my aux belt: water pump, tensioner, alternator, power steering pump, idle pulley, crankshaft pulley.

and you hear a squeal from the belt dragging itself across the pulley

Do you mean when this noise happens it's expected to see the water pump's pulley not spinning? Can this be a proof?

By the way, do you think the idle pulley must be changed? Consider it's still the original one from 2001, it spins very well as you could see from my video but I'm afraid the grease among its bearings is now almost dried out.

What about alternator? It was my first suspect because this noise is very similar to this other one of a failing alternator due to its bearings. Anyway I think we can exclude its pulley is the culprit because it spins smoothly and without noise as you could see from my other video but I think there's still a possibility that this noise is caused by its inner bearings that now are quite worn; consider it's the original alternator from 2001.

 

[SyntheticAtmosphere]

Hi all fellows!

This is my first thread and I'm glad to join your community. I'd like to share experiences with you about Ford cars and in particular my old Ford Fiesta, that I call my "baby"

Well, let's go to the point: this noise is driving me crazy (uploaded to google drive)!

It deals with my 2001 Fiesta MK4 1.25 16V gasoline.
It started on last January for the first and lasted only 3-4 days and then stopped, then it appeared again a couple of months ago for 2-3 days and stopped and last time it appeared last week.
It's a sort of weeeeee and it happens only when I start my car and for the first 10-15 minutes then stops and it's louder when accelerating. I guess it comes from the right part of the hood and in my car there's the timing belt and the auxiliary belt in that area therefore my bet it's caused by a faulty pulley, but wich one?

I've already tried to put off auxiliary belt to make some pulleys to spin by my hands and hear:
- A/C pulley spins very well and doesn't make any noise;
- idler pulley spin very well but it make this strange noise and I don't know if it's normal;
- alternator's pulley spins quite good and doesn't make any noise to my hear.

I'd like to ask you if you've ever experienced a sort of noise like mine and anyway if you can help me to identify what's its cause.
Thanks in advance

Check all your sheaves and clean them with brake cleaner or a solvent and a wire brush. Small brass brushes can be found at hardware stores that work great. Also consider replacing your belt as well. This ensures you have good belt "traction" eliminating possible slippage.
The idler pulley in the 2nd video sounds horrible, I think the bearings are dry. I would consider it for replacement.
The Alternator sounds fine as long as it keeps spinning after you let go. An alternator has a lot of rotating mass inside.
Power steering can be checked by putting a load on the pump (turn steering wheel with engine running) and listening for changes in sound. There will be a slight whine.
The water pump shaft should spin free, but have no in/out movement and should rotate smoothly with slight drag. You cant free spin a water pump like an alternator.
While spinning any pulley, vibration, grinding or howling noises indicate bearing issues. No pulley should be hard to turn either.
If you decide to replace the idler or tensioner pulley with just a pulley/bearing the bolt can be reverse thread so be careful. This wont be an issue if you replace the whole assembly.
If you cant resolve the issue within these parts, it is possible you have to look deeper.

 

[Handy Andy]

When you get squeals - the Serpentine belt is the "USUAL" cause for this because something on the route of the belt is hung up, frozen or unable to get enough friction to spin whatever it's threaded over. So the belt will also develop spots of wear that can be seen when the motor is not running.

Just open the hood - you can find some indications...


A seized belt oftentimes will lose it friction on the area it rubs

• - Because it rubs, it gets burnished and causes a loss of rubber
• - so it makes a "squeak spot" that can cause this "chirp" or even "stop completely" and squeal until the friction can be restored and the speed of the pulley driving it is reduced - so the belt can continue to turn.
• IT can "heat set" the bend in the belt so that went you take it off - it retains the shape of where it seized at and the longer it is left there to spin - the hotter that spot gets to a point it can burn off the belt completely.

So you said the water pump pulley / idler - seems ok, can you take a moment and post a pic of the motor? Fiesta motors from the different countries - their motors have changed or morphed into what we have as a Sigma - which seems to be Ford's Final effort in refining this motor (or cheapening it up.) to what we in the USA have to work with.

So I can only guess - since you're is 2001 circa - that means this motor you have is going to be a earlier version (MK4) so it may be a different type of line being more of a Zetec line or something more exotic.

By Vauxford - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=97384238
....From Wikipedia...​

So to say idler pulley seems OK, the concepts here are the same - they use the serpentine belt to turn the water pump - so my guess is once all other pulleys are checked - and the only thing questioning to making the noise still; is the Alternator - then change the Alternator.

But if you find the vehicle seems to overheat more - the serpentine belt will use it's upper smooth face to turn the idler pulley for the water pump because it usually does not need a lot of effort to spin because of the level of torque is not there - it's spinning a fluid - if it's not bent or binding.

But if you hear that squeal chirp or "EEEEEE-eeee" when you turn on an electrical load - then suspect the Alternator is showing it's wear and the belt and that part (the pulley it turns) is causing this binding noise. So replace it - this can also apply to the AC compressor too - it can show it's wear and make noises like this as the solenoid engaged the pulley and a load is on the motor for it.

 

[tabijan]

Maybe it’s an onomatopoeia thing but what I hear in the video is more of a whir than a whine or squeal. The idler pulley needs to be replaced even if it’s not the source of the sound, even if it feels like it spins smoothly.

With the engine idling try a quick spray of lubricant at the face of the idler pulley. If the sound changes, it’s likely the source of what you hear. Try spraying between the pulley and body of the other items driven by the belt except the crank pulley.

Sixto
2014 SE 1.6 hatchback 136K miles