Nearly put this in the Panda section but then, as it seems to afflict more than Pandas I decided to go here. The primary subject is Becky, our 2010 Panda 1.2 Dynamic Eco (so euro 4 engine with solid cam sprocket).

When we bought her, back near the turn of the year, one of the problems that came with her was, what sounded like, a worn alternator bearing. (although a tensioner or water pump bearing could make the same noise) during my long life in and around "the trade" I've heard plenty of them and was in little doubt. I was particularly interested to see what it turned out to be as my oldest boy's 2012 Punto 1.4 8valve (so variator type cam pulley) was making a similar noise but more quietly.

Investigations (disconnect fan belt) I thought, proved the noise to be something to do with the cam belt/tensioner/water pump on both engines. I didn't investigate further as both engines were getting Gates belt kits with water pump so I thought that would cure it. Both cars were done within short order and my boy went off happily with his after I had tried it out for a couple of miles down the road and back. At first I thought Becky was fine. I did a few trips out of the city to my other boy's house and drove around town - all seemed well. Then my wife started driving again after her eye operation so I was now outside the car listening to her drive down the road and on her return. Damn! Isn't that the bearing noise I heard previously. I removed the fan belt. Noise still there! Oh B****r! The noise is not noticeable in the car, although once you know it's there you can just hear it - Mrs J heard nothing! Standing in front of the car, especially with the bonnet up, it's really quite obvious. Most noisey from 1200 to around 1600 rpm. Much quieter at tickover and lost in general engine noise around 2000 rpm.

I really couldn't understand what was going on here so decided to have a listen to the Punto next time my boy called round. In the meantime I bumped into a fellow mechanic who I hadn't seen for some time and, in conversation, mentioned it. "Don't know about Fiat's but Fiestas do it and they have the same engine don't they?" Then the Punto turned up and there was the noise, not so loud as Becky but, definitely and quietly, there! Completely inaudible from the driver's seat.

Yesterday I went up town to try to find something to buy with the book token my brother gave me last Christmas! Standing at the bus stop I suddenly heard the noise! Turned round expecting to see Mrs Jock. But no, it was a young woman parking against the traffic with her cars nose in the bus stop, so right behind me. The car? A Ford Fiesta!

Well, I just couldn't wait to get stuck into Becky and find out what this phenomenon is. So I was up early this morning and, after taking Mrs J her cup of tea and ginger nut biscuit (our morning ritual) I got stuck in - to Becky! First off did an engine scan with MES - All OK! Ran her with fan belt removed, noise still there! Ok, engine mount, crank pulley and belt covers off (getting really good at doing that engine mount now!) So I'll run her with the drive exposed and go looking, only trouble is, SHE CRANKS BUT WON'T START! Oh Gawd! What have I broken? Probably one of those wires that are so difficult to get out of the groove in the plastic belt covers. Started looking for broken wires. Then, brainwave, plug in MES! Maybe it'll give me a clue! Oh yes! Crank position sensor! Great, at least I know what wire I'm looking at now! Oh! Wait a minute! It can't work without the reluctor ring on the pulley can it? Put the damn pulley back on YOU PRAT! Of course she then started right up!

Just standing hanging over the OSF wing the impression I get is the noise is in the area of the tensioner. I have two favourite tools when going looking for noises like this. A "proper" mechanics stethoscope and a leangth of nylon "listening" tube. A nice long screwdriver does the job just as well as the stethoscope but is rather more dangerous to use because you need to have the handle in your ear with the blade on the thing you're trying to diagnose so it's hard to see where you're poking it and if it slips - well!

I went for the stethoscope first. With the engine running I probed various parts of the block and cylinder head then stationary parts of the tensioner and water pump. Very strange! I can still clearly hear the noise but not through the tool! Both water pump and idler are running super smooth and quiet! Then I plugged my "listening" tube into my left ear (at my age it's important to use the "good" ear!) I started with the other end of the tube around the crank sprocket, all quiet. Moved up to the water pump, nothing unusual. Started moving across towards the tensioner and started to hear the noise! Ok, it's coming from somewhere around the tensioner/cam sprocket area. Very slowly and carefully (lots of fast moving stuff here) I moved the end of the tube around this area again and again. It's got to be the tensioner hasn't it? Well no actually because the noise is louder near the cam sprocket! But there's only a bushed bearing here so it can't be that (never heard one make a noise like this). So let's move the end of the tube very very slowly. Ok it gets most noisey with the end of the tube exactly opposite where the belt starts to run round the cam sprocket, right where the teeth on the belt are engaging with the teeth on the sprocket.

I never heard a belt do this before, and I've done lots of belts, but all older cars. In a way it reminds me of an over tensioned belt on a car with a fixed (not spring loaded) tensioner. OK let's have a cup of tea and come back to it. So, with tea mostly drunk, let's start again. How's the belt running? Absolutely text book case, not trying to run against the guides on the water pump or anything. Tensioner indicators lining up beautifully on top of one another. You can see them moving slightly with the engine running which indicates the spring loading is doing its job. Go back in with the stethoscope and listening tube - same result. The noise is definitely being produced by the belt meshing with the cam pulley. So why not where it meets the water pump or crank sprocket??. The belt kit was a Gates brand, I've used Gates for years and years and never had a problem. Double checked both on line and with supplier, definitely the correct kit.

So maybe they're all like this? The noise is not raucously loud but, once you've heard it you can't stop noticing it - like the Fiesta at the bus stop. Inside the car it's almost inaudible - out on the open road you don't hear it at all (and you only hear it from the outside on the Punto, and, although the same noise it's quieter than on the Panda). As I can't find anything actually defective, indeed everything looks absolutely A1, I intend to just keep on running both cars and see what developes. I would be very interested to hear if anyone else has experienced this strange effect and, if so, what was the outcome? I think the 1.2 euro 4 is non interference? Although I'm really pretty sure the Punto's in trouble if it's belt let's go?

Any thoughts anyone?
Looking forward to being told not to worry as they're all like this?
Regards
Jock.

You don't say on which side of the cam sprocket pulley the noise is coming from. By side I mean is this side where the belt comes off the tensioner and engages with the sprocket in a clockwise rotational direction or where the belt leaves the pulley on it's run to the crankshaft sprocket?

s130 said:

You don't say on which side of the cam sprocket pulley the noise is coming from. By side I mean is this side where the belt comes off the tensioner and engages with the sprocket in a clockwise rotational direction or where the belt leaves the pulley on it's run to the crankshaft sprocket?

Click to expand...

Thanks for the enquiry S130. Beginning to think everyone had fallen asleep or gone on holiday!

The noise is produced on the "leading edge" of the cam sprocket that is to say where the belt feeds into the sprocket teeth and begins to transfer drive. (after it has run round the tensioner) The sound is definitely nothing to do with the tensioner and is confined, very locally, to just where the teeth begin to mesh on the cam sprocket. There is no sign of it on the other side of the sprocket where the belt is leaving to travel on to the crank sprocket and there is, strangely, no similar noise at the water pump or crank sprockets! This would seem to indicate that the sprocket is the problem however I checked the mesh of the teeth by wrapping the belt right round the pulley by hand before fitting and the mesh was perfect. I also checked the teeth for damage and debris before fitting. The guide flanges on the water pump sprocket determine where the belt runs on the sprockets and I notice it runs quite towards the back of both the cam and crank sprockets, just as it did with the old water pump in place - you can see the "clean" area on the sprocket where the old belt ran. I would have preferred to see it running more in the middle of the sprocket but I notice the photographic illustrations in the Haynes manual show the belt on their car running the same. The belt is fully engaged with the sprockets and not rubbing against engine castings, covers or anything else. As previously mentioned I've carefully checked that the belt kit was the correct one and I'm convinced it is. I'm a bit obsessive about cam belts!

The Punto noise is virtually identical in every respect but considerably quieter. To such an extent that, actually, I'm not all that worried about it and I could be convinced that it was a normally acceptable noise - just. The noise the Fiesta made was also exactly the same but somewhere in between the Panda and Punto in volume. I could hear it quite easily at the kerbside, with moderately heavy city traffic passing by, as she tooed and froed parking it.

So far I've only one theory in mind, and it's a pretty tenuous one. Observing the run of the belt in relation to the sprockets I find myself wondering "why would you design it so the belt runs almost on the back edge of the sprockets and not use the full width?" Then I started thinking "what controls the run of the belt?" answer, The guide flanges on the back and front of the water pump sprocket. This engine has been around a long time, I wonder if, in its original form, it had a gasket on the water pump? that would have jacked the pump out from the block and made the belt run more in the middle of the sprockets wouldn't it? then when they started using sealant on the pump instead (so it would be a little nearer the block) they just let the belt run more towards the block?

Oh well, it was a good theory. Just remembered I've still got Felicity's Haynes manual in the garage (Felicity was our 1992 Panda Parade). She had the old engine with the narrow, course toothed, belt. I did 4 belts and one water pump on her over the many years we had her but couldn't tell you if it was fitted with a gasket or sealant - This getting older really is a pain! - Hauled it out and there are very clear pictures showing the pump being fitted with a bead of sealant - no gasket! It also very clearly shows the belt running right on the back of the sprockets - no mistaking it - so these belts all run like this, very strange?

Well I think we may have a narrowed down possibility.

Lets take these in stages/steps.

1) The cam shaft/sprocket is a major drag/load by definition and function.
2) The crank shaft sprocket has to pull hard on the belt to drive the cam shaft sprocket
3) 1) & 2) together would/do mean the cam belt is under significant tension and thus there is less free play for the belt to vibrate / shimmer / etc on the "down side"
4) The "up side" tension is regulated by the tensioner and the belt will never be under the same tension as the down side run
5) 4) suggest more ability/latitude for belt ability vibrate, whip, shimmer etc.
6) Anytime a belt or chain engages with a sprocket the engaging edges have to align and settle "into the grove". Chain drive sprockets have shallow entry angles and deep troughs and the chains have inbuilt rollers. However typical cam belt drives have more vertical engagement surfaces that are also less deep.
7) Given 6) then engagement noise of belt to sprocket will I guess be louder. Couple belt materials, tolerances of tooth dimensions, tensions, etc. then increased noise is a distinct possibility.

From my experience (I've done many a cam belt change) the only "noise" issue I have encountered are:

1) Some belts "groan" even when tensioned correctly. *Fractionally* releasing the tension solves the problem (manually adjustment belts)

2) Dynamic / Sprung loaded tensioners when incorrectly set will "knock" against their end stops. Normally only noticed on engine start-up and when cold (i.e. more lumpy running)

Belt "Groan" can sound just like a bearing issue so this may be a starting point. However if you have no manual adjustment of belt tension then there is nothing you can really do other than try a different make of belt and/or tensioner.

Not sure what else to add.

The later Ka was a 500 in a cheap frock, so used the 1.2 FIRE engine. I'm not aware of any other Ford using a Fiat engine.

So if the noise is apparent on the Fiat and a Ford, we are probably hearing a 'normal' noise for belt meshing. I've never experienced a completely silent belt, they all make some sort of noise.

You need to stop listening, you'll only worry, and it'll grow. Then I'll have to try and spell paranoia.

Thanks very much for that S130. It all makes a lot of sense! Having tried and checked out everything else the tension is the only thing left to play with. At this time the tensioner, which is an automatic spring loaded type, is set so that the pointers line up when the engine is dead cold (overnight). During my checks I noticed that the pointers move out of line towards the "tight" side by a fair amount when the engine is fully hot (fan running) - no doubt due to expansion of the head and block increasing the centre distance between the crank and cam centre lines. I think I'll try setting up the tensioner so the pointers overlap with the engine hot. This should slightly reduce belt tension. Then we'll see if it makes any difference to the noise. If it does some serious thinking will need to be done! Although I'm now thinking that actually it's probable that nothing is really "wrong" and the noise may well improve if I just leave it alone to settle in some more (it can't have done more than 2 or 3 hundred miles since fitting at most)

Many thanks for your excellent reply which has helped "the little grey cells" to think outside the box they had confined themselves to!
Kindest regards
Jock

Thanks PB that's cheered me up no end! I'm not joking, it really has! Oh, and can I join your gang? - spelling was never my strong point and guess what? My youngest boy is mildly dislexic and they say it's passed through the male line! Of course dyslexia wasn't invented when we were young!
Kindest regards
Jock.

Woah! Thought yesterdays "mucking about" had cured it (the noise) for a few minutes this morning! After quite a spell of dry weather we have had quite persistent and heavy rain through the later part of the night and it's only starting to tail off now (mid morning). Just went out to check on Becky's incontinence problem (water leak in boot) which I have been trying to resolve, but had to move her to be able to open the garage door (she's outside on the hard standing). Jumped in and started her up. WOW! I don't hear the noise! Jump out and open the bonnet, Oh well, it's still there but a LOT quieter! Great, Yippee! Wonder what I did that's caused this improvement? Oh damn, and another expletive, and another expletive, I've forgotten to put my hearing aids in!!!

Pugglt Auld Jock said:

Oh damn, and another expletive, I've forgotten to put my hearing aids in!!!

Click to expand...

A great way to 'cure' all unwanted noises. An alternative to increasing the radio volume.

So I gather you adjusted with engine hot and it got quieter?

Or was it the moist lubricated air smoothing the belt/sprocket meshing?

Not tried this on a cam belt but on other belts (eg fan & auxbelts) when they are new they are often super clean, dry etc. and sometimes noisy. Their newness/cleanness also tend to clean the pulleys they go round. On occasions I've had this I've just given the belt (when running) a quick one second mist spray of Holts Wet Start. SILENCE!

I bet you if you rub the old cam belt teeth and grooves it will deposit grime on your cloth. New belt wont. So old well run belts pick up self lubricating contamination over time and thus run quietly as opposed to "squeaky" clean new ones.

s130 said:

So I gather you adjusted with engine hot and it got quieter?

Or was it the moist lubricated air smoothing the belt/sprocket meshing?

Not tried this on a cam belt but on other belts (eg fan & auxbelts) when they are new they are often super clean, dry etc. and sometimes noisy. Their newness/cleanness also tend to clean the pulleys they go round. On occasions I've had this I've just given the belt (when running) a quick one second mist spray of Holts Wet Start. SILENCE!

I bet you if you rub the old cam belt teeth and grooves it will deposit grime on your cloth. New belt wont. So old well run belts pick up self lubricating contamination over time and thus run quietly as opposed to "squeaky" clean new ones.

Click to expand...

By the time I got round to reading your excellent advice I had already reassembled it all and Mrs J was planning some shopping. I made no changes so the belt and tensioner is as when I fitted it some weeks ago - that is with engine dead cold after having stood overnight and tensioner set with pointers overlapping as recommended. At that time I thought I had a bearing problem and, as the tensioner was set as per the recommendation, I wasn't thinking about belt tension perhaps being the culprit.

Now though, I have the advantage of knowing that there is nothing wrong with the installation, bearings, belt itself, alignment, sprockets, etc and the tensioner is adjusted as recommended and is not spring bound. I also like your suggestion that it may be the very newness of the belt itself which is giving this noise. So I've decided to let the belt "run in" for a while and see if it quietens down.

I would be a little reluctant to spray the belt with anything, although many years ago I recollect seeing a spray can of "anti slip belt dressing" which was used on V drive belts on an industrial electric motor's pulley drive. In this instance if the noise persists I will first try blowing chalk powder on it whilst it's running (had success with this in the past when diagnosing squealing V belts. After that I may try setting up the tensioner with the engine fully hot. However it may be that it will settle down by itself after a while. I will soon be visiting my brother who lives in the border country (historically our family are borderers) so I think that if I take Becky that will give her a nice run to settle it down.

Thanks to you all for your contributions which have been very helpful in getting me to think about this with a broader take on it all.
Regards
Jock.

Pugglt Auld Jock said:

Thanks to you all for your contributions which have been very helpful in getting me to think about this with a broader take on it all.
Regards
Jock.

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You are welcome Jock.

I would never ever claim to be an expert, let alone absolutely correct/definitive UNLESS I state so when pressed on any given point.

All I have, like many others here, is many years of experience, some based on trial and error (the best way to learn) and a good general engineering background etc.

You nailed the most important issue/fact - THINK ABOUT THIS ......

In the heat of the moment even the best of us fail to step back and THINK / REASON/PONDER/etc. I'm dead guilty of this when my back is against the wall and time is not on my side. It is plum easy for me/others to chip in when we are not in the hot seat.

This/your thread has raised an issue I've never encountered before so it is a WIN / WIN for everyone.

Keep us all posted when hopefully the belt beds in or the chalk comes into play.

Ummmm, experts. A dangerous word! I know people whose depth of knowledge about a particular subject is so deep I would automatically defer to them in an argument but when you start calling someone an expert then their "take" on a problem is treated like a pronouncement from a religious deity and tends to then stifle lateral thinking. In legal situations it can be downright dangerous!

"In the heat of the moment" can be a very "dangerous" time! When something goes wrong, for instance my recent non start incident (see above) I find I have a tendancy to always assume the worst! As in the above incident where I immediately assumed that I'd damaged the wiring loom when actually all I'd done was deprive the crankshaft sensor of the ability to generate a signal by failing to reinstall the pulley! Wisdom comes with age they say, and I've learned, in these situations, to put the tools down, make a nice cup of tea - in my earlier years I would have lit a fag too, but I gave that filthy habit up many years ago - and have a quiet sit down for a minute while you think about it. Charging on heedless often causes more damage!

I will certainly post again when I've got enough mileage on her to be able to judge an outcome. All is not disappointment though as the repair to the rear hatch water leak, which I have a thread running about in the Panda section, is staying dry! WhooHoo!

@Pugglt Auld Jock this thread is almost identical in relation to an issue which I'm currently experiencing, the only difference being that the engine in question is a 1.2 8v 69hp Fire in a 2011 plate car.

I was wondering how things turned out? Did things quieten down as time went by and the belt(s) got ran in?

Thanks

Nige1975 said:

@Pugglt Auld Jock this thread is almost identical in relation to an issue which I'm currently experiencing, the only difference being that the engine in question is a 1.2 8v 69hp Fire in a 2011 plate car.

I was wondering how things turned out? Did things quieten down as time went by and the belt(s) got ran in?

Thanks

Click to expand...

Apologies to all, I was going to post when I'd got some running under her belt wasn't I. Well, here we are just over 5 years later but only having done around 10,000 miles - the car is Mrs J's shopping car (and my hobby project). The noise really hasn't changed to any degree sounds exactly the same, possibly very very slightly quieter if you really insist on splitting hairs.

When I was originally diagnosing this I spent quite a while very carefully pinpointing the source of the noise. It sounds very much like a worn tensioner or idler bearing and I checked both with my automotive stethoscope and my listening tube. This was done before the belt guards were replaced so with no fan belt on and alternator and air con pump undriven. The stethoscope, which picks up noises via a probe which you place in contact with the metal casting of components - so engine block, cylinder head, alternator body, water pump body, etc I've found to be very good for isolating worn ball/roller races - many of us will be familiar with the technique of using a screwdriver or metal rod resting on a casting/casing with the other end stuck in your ear, vibrations through the castings of the engine will be loudest when the end of the rod is nearest to the worn bearing. In this instance there was really no unexpected noises detected, certainly none related to worn bearings.

Next I brought out my listening tube. A listening tube is used by sticking one end in your ear and moving the other end around the area where you think the noise is coming from. Almost any tubing will do but something like heater hose will be too cumbersome. I prefer something like fuel piping or screen washer tube. I'm actually using a length of nylon tubing which seems particularly good at transferring the noises with out loosing volume, probably due to the rigid nature of the tubing. You don't touch any component part with the open end of the tube, as you would with the stethoscope/screwdriver, just move it around where you think the origin of the noise is. It was while doing this that the noise was easily heard and was at maximum volume whenever the open end of the tube was hovered over the area where the belt fed into mesh with the camshaft sprocket. I'm absolutely sure it's the teeth on the belt meshing with the teeth on the pulley which produce the noise - similar principle to a siren?

The garage where I bought the car assured me that some do it and some don't. I didn't believe them so, shortly after I bought her I fitted a complete Gates belt kit, so timing belt, tensioner bearing and water pump and it's made really no appreciable difference at all - which you might expect if it was a bearing. I took her down to my local Fiat Indy and got the same advice, "some do it and others don't and it's not just the Fiats, we've heard it on the Ford Ka too" - same engine of course.

That belt is now 5 years old, although the mileage is very low it's been the worst sort of running for the belt ie. stop/start shopping, so, if she passes her MOT next month, she'll be getting another belt this summer when the better weather returns (I don't do longer jobs outside in the cold any more). I'm going to source a genuine Fiat belt this time just out of interest to see if it makes any difference.

As people who've read some of my other posts will know, I try to get a good walk in every day and this always involves some pavement work where, because I'm interested in almost anything on wheels, I pay attention to the vehicles going past. Every now and then I hear "the noise" and when I look up it's pretty much always a Panda 169 model making it, but by no means do they all do it. Interestingly, maybe? I've not heard it from a later model Panda. These will have the VVT camshaft pulley/sprocket so not the same as our earlier solid sprockets. I'd been wondering if it's as simple as a tolerance problem with the machining of the older type sprocket? However your engine, being 2011 and a 69hp will have the VVT sprocket so that seems to be that theory out the window.

If she passes her MOT - big question mark last year over her rear axle being corroded - then I'll try to remember to post here as to what effect fitting a genuine belt had. Don't hold your breath though as it's not going to be within the next couple of months.

Thanks for your reply.

The description sounds similar to what has recently happened with my daughters car following a belt, tensioner and water pump change.

Prior to changing the belt, pump and tensioner no noise could be heard but on doing so it could, as you did I purchased a Gates kit.

My method of diagnosing the source of the noise is not as good as yours i.e. equipment used, but similar in effect by using a length of metal bar to listen against and this draws me to the same conclusion.

I have held the bar against the pump, compressor and alternator and the noise I can hear appears to be coming from the area which you describe. The belt cover when I'm using the bar but the noise can clearly be heard from that location.

Originally it was a concern but not something which is now, I also did and still do wonder what it would be like with a Fiat belt fitted.

Years ago no my Tipo 1.6SX which I replaced the timing belt on three times. After changes there was a noise/groaning that I could never get completely rid off. Basically the belt was too tight and to reduce the noise you had to slacken the tensioner off whilst checking for excessive "whip" due to a too slack belt.

On the Tipo the tensioner was the old static type and not the more modern sprung loaded ones with the pointer setup.

I did ask a Fiat technician about the noise an he said that some make this noise and it is very difficult to get rid of and keep the right belt tension.

With the modern sprung loaded tensioners then there is not really anything you can do as the belt tension is constant in the "window". If the pointers are set either too low or too high apart then the tensioner will "knock" against it's end stops and ultimately fail.

s130 said:

Years ago no my Tipo 1.6SX which I replaced the timing belt on three times.

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Slightly OT, did the timing marks line up for you?
I found the cam needed back (or forward) 1 tooth ot it ran really sluggish.

vexorg said:

Slightly OT, did the timing marks line up for you?
I found the cam needed back (or forward) 1 tooth ot it ran really sluggish.

Click to expand...

Timing marks were all OK as far as I recall. NOTE! I used the flywheel marks on the flywheel/bell housing to set TDC. Far more accurate.

Also, I can't recall if this was on the Tipo, on some Fiat's the timing for TDC is done on number 4 cylinder and not number 1.

It was a bit of an anticlimax for me, thought I'd found the timing out and it would run better when timed correctly, then had to redo it again back to the 'wrong' timing.