Technical Is it REALLY necessary to change the timing belt?!

Currently reading:
Technical Is it REALLY necessary to change the timing belt?!

Basic answer YES if I bought a car with no sh at that mileage I would definitely change the timing belt as soon as possible, i might risk it till 60k ? I think the fire engines make people feel safe ?? almost like well if it does snap at least my engine will be ok....hmm I wouldn't rely on that, to do a timing belt isn't that expensive on its own, to save money buy the timing belt kit yourself along with the water pump + fanbelt, think I paid under £80 for them off ebay (£30 timing belt kit, £40 water pump and £10 fan belt) then just pay labour price that's what i do to save money, no VAT why would i pay that,? cash always then you can negotiate better price. Everyone will say do the water pump and fan belt at same time as timing belt but you don't have to, lets say you cant afford to do it all right now the main thing is the timing belt I'd say, you can always do the water pump + fan belt at later stage, if money is no issue then yes do it all at once. Depending on what kind of labour rate you can get I'd say 4 hours labour roughly so if you buy the parts yourself maybe £200-300 for whole job. Hope this helps
 
yeah, I think I paid about just over £300 for the Timing Belt replacement by Fiat Dealer garage. Wasn't cheap for my pocket, but I went ahead because at the time I believed it was an important service for the car.
 
Basic answer YES if I bought a car with no sh at that mileage I would definitely change the timing belt as soon as possible, i might risk it till 60k ? I think the fire engines make people feel safe ?? almost like well if it does snap at least my engine will be ok....hmm I wouldn't rely on that ...

Sod's Law says an old cam belt will go titsup on the motorway fast lane at 5pm on a Friday. For something that will have to be done soon enough and will probably outlast the car why take the risk?
If you don't feel able to do the whole job yourself, you can remove the various covers, saving the mechanic's time and reducing your costs.
 
Could it be done by home DIYer?

I would give you a cautious yes on that. Not because the task is in itself of extreme difficulty but because the consequences of getting it wrong on an interference engine are ruinous. However as our earlier type Panda engines are supposed to be non-interference we should all be OK even if we get it timed up wrong? All that should happen is it won't run!

In the Grande Punto section there is an absolutely excellent guide on how to do it, by Andy Monty, in the Guides section (top left of page) and Charlie (Veresecrazy) has another very worth reading in this Panda section (see Guides).

I had a bit of a stab at describing it when I did Becky's back at the beginning of last summer - to read search back to 09/06/2018 (page 17 at this time) in this Panda section - It's entitled "Becky's timing belt - the ongoing saga". On older simpler engines the manufacturer would cast or machine timing marks into the pulley/sprockets (shall we just call them pulleys?) with corresponding marks on the front of the engine against which these marks were lined up. This made life simple with no special tools required. The pulleys would be mounted to the crankshaft and camshaft using keys or dowels so could only be installed in one position. So, as long as you lined up the pulley marks with the corresponding marks on the front of the engine whilst installing your new timing belt, you really couldn't get it wrong. (but, unbelievably, people still did!).

Newer engines are now tending to have at least one of the pulleys with no key! So if you slacken the retaining bolt the pulley will spin freely on the end of the shaft. The result of this is, of course, that the timing relationship between the crankshaft and camshaft is lost. To set this "phasing" relationship up correctly again requires a kit of timing tools because with no key on the cam drive there's no fixed point of reference any more! You can buy them on eBay at around the £40 mark (I bought the "Nielsen" branded kit, Pictured in the post). On our Panda 8 valve "FIRE" engines it is recommended to slacken the cam pulley retaining bolt - just by half a turn or so, enough to free the pulley on it's shaft. It's not splined or anything, as soon as you slacken the bolt it will be free to spin without driving the camshaft - However I couldn't see why it is necessary to loosen the bolt in the first place if you make your own timing marks. Which was a common way to do it in my "workshop days". Oh, by the way, from what I've read, it's very very tight! - another good reason not to undo it. Of course it then needs to be done up again, very very tight! (I'm a great believer in letting "sleeping dogs lie")

I set out to check this on both our 1.2 euro 4 Panda and my older boy's 1.4 Euro 5 Punto - both of which needed belts done. Before slackening anything off I made marks (Tippex) on the crankshaft sprocket and corresponding marks on the old belt and oil pump casing then, up top to the cam sprocket, belt and cylinder head/cam cover. Then I removed the old belt, leaving the cam sprocket bolt fully tightened and transferred the marks from the old belt to the new one, replaced the old water pump with a new one (don't believe in doing a belt, where the water pump is part of the drive train, without renewing the pump) and fitted a new tensioner before fitting the new belt so that the transferred marks all lined up as they had before the old belt was removed.

If my theory was correct that should be the job done. So, just to be sure, I removed the cam cover and fitted up the cam locking tool to the right hand (passenger side) end of the camshaft and offered up the crank locking tool. Guess what? it all lined up absolutely millimeter perfect! The same worked on the Punto, which I thought it would but was less sure of because it has the VVT cam sprocket. Of course, and it's a big OF COURSE, if you do it without the tools and rely on your tippexed marks then you are setting it all up to be as it was before you started work. The problem with this is that you can't be sure the sprockets were set up correctly before you started. Unless you know for sure that this is the engine's first belt change (surely the factory will have set it up right when they built it) or you have worked on it yourself before and know, because like me you used the timing tools to check, that the timing is originally correct.

So, for future belt changes on our cars, I won't need to remove the cam cover and other "awkward" ancillaries when we get to belt change time which should save a considerable amount of time. I would not like to do an engine whose history I did not know without using the timing tool kit.

Apparently it is not unusual to perform a "Phonic Wheel Relearn" after renewing a cam belt on these engines. Our local Fiat main dealer said they always do as a matter of course. I used a Gates All-in-one kit which includes the water pump and has quite a good fitting guide included. It stated that an "ECU Relearn" will be needed on completion. So another thing I was interested in checking out was whether a "Phonic Wheel Relearn" would be necessary if you didn't disturb the sprocket bolt. For those who don't know (and I had never heard of a "Phonic Wheel" until we bought Becky - There had never been any reference to it with Felicity - our older 1992 Panda Parade) These later engines have a sensor reading on the crankshaft pulley which mainly tells the ECU where the pistons are and what RPMs the engine is turning so it knows when to fire the plugs but they also have a sensor reading on the camshaft pulley which feeds signals to the ECU enabling it to decide which plug to fire when and, I believe, small trimming adjustments to the timing to take place. - maybe does other "stuff" but I wouldn't know about that. The ECU learns the expected relative position of these two shafts (crank and cam) and if it sees something unexpected it will flag up a DTC (Diagnostic Trouble Code) and store it as an Error which you can read with the likes of MULTIECUSCAN and light up the check engine light on the dash. It can detect minute changes in this relationship. (by the way, I have read that it often mistakenly interprets this as a misfire code which can really fool people who don't know about it! There are posts in our forum about people who have spent substantial amounts of money renewing plugs, plug leads, ignition coils, etc trying to rectify this when what is actually needed is a "Phonic Wheel Relearn" performed using either the genuine Fiat dealer computer or Multiecuscan. By the way, there is a bit of an obvious "give away" clue on this one. People who have experienced it say that although the ECU was logging a misfire code there was no detectable misfire when driving!

If you have had the cam sprocket bolt slackened, as is recommended, during the replacement of the timing belt then I can see that there may be a very slight difference in it's angular relationship with the camshaft which will likely be picked up and cause a DTC to be stored and the check light lit. I wondered though that if you don't touch that bolt - so don't alter the relative position of the cam pulley to the camshaft - and with the exceptional accuracy with which modern synchronous belts (that's another name for the kind of toothed belt used as timing belts) are manufactured, they say that they don't really stretch either, then surely there would be no detectable difference between the old and new relative running positions of the two pulleys so timing would be spot on and so no error detected by the ECU so no EML (Engine Management Light) lit either.

Well I'm pleased to be able to report that, more than half a year later, neither car has lit it's EML. For which I'm very glad as I still only have a sketchy idea how to perform a Phonic Wheel Relearn with my Multiecuscan program!

By the way, on the Panda, probably the most difficult bit is slackening the two (of four) engine mounting bolts which hold the mounting to the front of the engine and "hide" under the mounting itself. the mounting on the Punto is almost identical but easier to tackle as access is better (more room between the inner wing and "front" of the engine).

So, Theleman, You sound to me like the sort of chap who could do this! Read all the guides and have a very good look at the engine first. If you're feeling good about it have a go! It may well take you longer than you think so prepare for what you're doing for transport if it takes more than a day - don't rush it! Often ends in disaster if you do. Also worth thinking about who could help if it goes wrong and you can't complete the job? The first one I did gave me tremendous pleasure when it fired up and idled nicely - I had a smile on my face for days! Last word of advice? On any engine, particularly if you know it to be an interference design, Remove the spark plugs so you can turn the engine over easily and slowly and gently turn the engine - spanner or socket on the crankshaft pulley centre bolt - through two complete revolutions feeling all the time for any resistance (which you will feel if a piston is making contact with a valve) You need to do this slowly, stopping the instant you feel any resistance, because if you do if fast the flywheel will contain sufficient energy to bend a valve head before it stops. Do this BEFORE even thinking about hitting the starter. The engine turns so fast on the starter it will ruin it if you've got it all wrong! By the way, always turn an engine in it's normal direction of rotation - turning it backwards can de-tension the tensioner and make the belt (or chain on chain cam engines) jump teeth and put your carefully set up timing out of synch!

Well, that was another of my lengthy posts wasn't it! Hope it's been of use to some.
Stay well all
Jock
 
Last edited:
Just to reiterate what is posted many times on here:
A failing bearing..

Waterpump or idler.. will allow enough 'slack' on the belt..( due to the fixed tensioner..)

For the belt to jump MANY teeth..
My record is 7 teeth..

Obviously on the early FIRE it can just be retimed..once the dodgy parts are dealt with.

However.. the motor WILL NOT RUN .. so you risk a potention accident.

Choice is yours.. but £60 ON A TIMING KIT seems well spent VS a NEW PANDA.
 
This explains what has to be done.



It's an annoyance having to remove most of the front wheel arch undertray just to remove the little engine cover but most of the job is ok.

The video shows the non aircon version. If you have aircon, the auxiliary belt is removed by slackening the tensioner from under the wheel arch.


He uses a special beam to support the engine. A 3x2 wood batten with some blocks at each end would be enough. I did my Punto with axle stands under the engine sump flanges - not the sump pan itself.

He does an excellent job of draining the coolant, but if you have a big enough tray, just loosening the water pump will drain the coolant though less gently. Note where the bleed points are.
 
Good morning Charlie. Felicity, our old '92 Panda Parade had exactly that type of "old school" tensioner. The tension was applied (I think I used a pair of right angle circlip pliers if I remember) then the securing nut was tightened and that was that. As you will know, getting just the right tension on the belt with this design is quite difficult - very easy to under or over tighten - and once the securing nut is tightened that's it - there is no provision to take up any clearance which develops as the belt settles in. I always rechecked the tension after a couple of thousand miles and, more often than not, there would be a small adjustment to be made.

So I was very pleased to find that Becky has the spring loaded type where all you need to do is rotate the fixing until the pointers line up, tighten the fixing nut and the tensioner spring ensures the correct tension is maintained for the life of the belt. I was even more pleased when my boy's Punto turned out to have the same arrangement!

In theory, if a bit of wear occurs in either water pump or tensioner bearings, the sprung tensioner might be able to take up the slack - which the "solid" tensioner would not - In practice I wouldn't be risking it, which is why I always change both tensioner and water pump when doing a belt.

The argument about saving the relatively small amount of money involved in doing the water pump (and it will cost a lot more if it subsequently fails and the whole thing has to be then stripped down again to do it!) just doesn't make any sense to me and the whole thing will seem pretty academic when you are sitting in the fast lane with a dead engine on a dark and rainy night with the kids screaming in the back seats!

So, absolutely Charlie, I am of the same opinion as you. Regardless of what type of tensioner your engine has or how many miles you want to gamble on getting out of the assembly, The manufacturer will have tested and made calculations as to what the maximum reasonable running time, under average conditions of usage, it's reasonable to expect and based mileage/time intervals on that. I'm sure a safety factor will have been built in so it's likely that it will last longer, but then it boils down to how confident a gambler you are? (can't help thinking of Dirty Harry at this moment - "Do you feel lucky punk, well do you?")
 
This explains what has to be done.

https://www.youtube.com/watch?v=fxJjFLfVlPM

It's an annoyance having to remove most of the front wheel arch undertray just to remove the little engine cover but most of the job is ok.

The video shows the non aircon version. If you have aircon, the auxiliary belt is removed by slackening the tensioner from under the wheel arch.


He uses a special beam to support the engine. A 3x2 wood batten with some blocks at each end would be enough. I did my Punto with axle stands under the engine sump flanges - not the sump pan itself.

He does an excellent job of draining the coolant, but if you have a big enough tray, just loosening the water pump will drain the coolant though less gently. Note where the bleed points are.
An excellent video Dave, and using my favorite brand of belt too! I watched this quite some time ago before doing Becky's belt. My memory is not good these days but doesn't this show colored markings on the belt and sprockets which are used for the lining up? (I'm off to view it again when I finish with this) I have a vague recollection of looking for these marks on my boy's 2012 Punto 1.4 8 valve when I did it's belt but couldn't find them?

I was shown, many years ago now, to support the engine on a trolley jack under the sump pan with a thick piece of plywood to spread the load. I've never had a problem doing it this way and keep a "special" piece of plywood for the job, although I did hesitate for a moment before proceeding with my boy's Punto which has a very crusty rusty sump! (My thinking was though that if it couldn't take it I jolly well ought to be doing a sump on it anyway! A job which is now scheduled for when (if?) the good weather arrives this summer. Perhaps strangely, because they are usually stronger, I worry more doing it this way with an alloy sump but that's more to do with the potential cost involved in the buying of the replacement.
 
Last edited:
An excellent video Dave, and using my favorite brand of belt too! I watched this quite some time ago before doing Becky's belt. My memory is not good these days but doesn't this show colored markings on the belt and sprockets which are used for the lining up? (I'm off to view it again when I finish with this) I have a vague recollection of looking for these marks on my boy's 2012 Punto 1.4 8 valve when I did it' belt but couldn't find them?

I was shown, many years ago now, to support the engine on a trolley jack under the sump pan with a thick piece of plywood to spread the load. I've never had a problem doing it this way and keep a "special" piece of plywood for the job, although I did hesitate for a moment before proceeding with my boy's Punto which has a very crusty rusty sump! (My thinking was though that if it couldn't take it I jolly well ought to be doing a sump on it anyway! A job which is now scheduled for when (if?) the good weather arrives this summer. Perhaps strangely, because they are usually stronger, I worry more doing it this way with an alloy sump but that's more to do with the potential cost involved in the buying of the replacement.
Yup, colored lines and marks, just as I remembered, Didn't find/use them on the Punto just made my own tippex ones.

Just an observation but one thing I noticed on both our Panda and Punto is that the belt runs towards the back of both the crank and cam sprockets. I mean by that it's not "centred". If you look at this video you'll see it's the same on this engine, the teeth are visible at the front of the sprocket but the belt covers them at the rear. You would think the belt should run in the middle wouldn't you? Of course this positioning is controlled by the flanges on the water pump pulley so there's nothing you can do about it but it has set me to wondering if the original design incorporated a thick gasket between the pump and block face which now a days has been replaced by sealant so moving the pump nearer the block? I really can't remember clearly but I have a vague memory of there being a gasket involved when I did Felicity's ('92 Panda) belt many years ago?
 
WOW great posts Jock and Thanks for the vid Dave.
Thanks.

Yes, I would love to tackle the work DIY, but my Panda has new timing belt since last year, so it will be another 50k miles or 5 years until next one?
So we have some time until due for another timing belt replacement for this Panda if we still kept the car of course.

If I managed to get hold of a beater old Panda or any very cheap simple old car to run around in town and fiddling about learning, and then I will have a go on that one.

I will be re-reading the posts a few times repeatedly to soak in all the points and details as much as I can meanwhile :)
 
Last edited:
With the Panda 8V its really a case of swapping the belt and keeping the timing marks correct. There is no interference on the 60HP versions so not a biggie if you mess it up. But even on the later "contact" engine its only a case of checking the alignments before turning the engine. If/when that is done, do it very carefully by hand with plugs removed and stop if there is any resistance coming up to top dead centre.

After fitting the new belt, I'm not entirely convinced it's necessary to turn the engine at all. If the pulleys have not been removed, the timing marks on cam and crank are not going to change. Tensioning the belt could pull it out of line or the belt could jump a tooth but you would be able to see the miss-match from the timing marks.

Assuming all was fine with the old belt it should be just as good with the new one.
 
Thanks for the post
I've been quoted £275 by a Leeds indy to replace the belt, pump, pulleys etc - seems a bit toppy but is that OK do you think?
 
Thanks Dave,
Yep, seems about the going rate for parts and around 4 hours labour?
Has anyone used Walkers in Northallerton for those in N Yorkshire, they are my nearest Fiat indy I think.
I wish I had pressed for the belt to be done before I bought it, but he has put a couple of new Continental tyres on the front wheels and it was £1300 so didn't think it was a bad deal in all!
Thanks again for everyone that replied.

Still need to see if the sun blind retaining clips are replaceable as think the sun in summer (if we get another like last year) blazing through the sky dome with no shade might become tiresome!!
 
Open the bonnet and locate the oil filler cap. Is it a square rubber pull out thing? If so this is an older engine and, as far as I know, safe, - our old Panda Parade was like this. If you have a round "twist to remove" cap then look to the rear of the cam cover and just to it's right and if you see a small (maybe 2" long) cylindrical device with an electrical connection on it's rear end then this is the VVT camshaft sprocket actuating solenoid. This means it is an interference engine Euro 5 (introduced I believe around 2011 on the 1.2 - the 1.1, I believe, was always "safe). Our 2010 1.2 is Euro 4, has the round filler cap but just a blanking plug in the cam cover where the Euro 5 has it's solenoid and no VVT and is "safe" as far as I know. The "safe" 1.2 is 60hp and the one with the VVT sprocket (thus "unsafe"?) is rated at 69hp Your owner's manual - is it on the V5? - may quote which engine you have so it may help to know this.
Hi Jock
Finally got the car to look and yes, it's the square rubber plug thing so seems I'm 'safe'!
Being a total non mechanic, can you see the belt to see if it's cracking/perished?
To the left of the bay towards the rear?!

Thanks again for the info,
 
Hi Jock
Finally got the car to look and yes, it's the square rubber plug thing so seems I'm 'safe'!
Being a total non mechanic, can you see the belt to see if it's cracking/perished?
To the left of the bay towards the rear?!

Thanks again for the info,
OK Yours is a bit older but probably still identifiably like mine. Looking at the driver's side of the engine It should look similar to this?

P1080297.JPG

The two aluminium pipes are to do with the air con. So if you don't have air con you won't have these pipes. If you look at the upper right hand part of the image, behind the air con pipe, you can see a plastic cover with a label stuck to it (I can see a 2 on the label). That is the top cover for the cam belt - the cam belt (timing belt some call it) can only be seen if you remove this cover. To change the belt itself that engine mounting, in front of the cover, has to be completely removed - so the engine has to be supported to stop it dropping on the ground - and the bottom fan belt pulley and bottom plastic cover also have to come off. Not really a very hard job for an experienced mechanic Then the tensioner bearing has to be unbolted so the old belt can be removed and, if the water pump is being renewed as well (which I would always do because if you leave it and it subsequently fails you will be taking all this to pieces again - you will be paying twice!) but, understanding what has to be done, may help you understand when we say the price quoted to you seems reasonable.

If you look to the left of the image you can see two small hex bolts which are holding on a plastic molding - just below the clutch fluid reservoir. Just below these bolts you can catch a wee glimpse of the smooth back of the fan belt, which, of course, has to come off too! Here is a rather better view of it:

P1080296.JPG

The fan belt on earlier engines (like our '99 Panda Parade) was a simple "V" belt. The older "V" belts were just that with the belt section being in the shape of a "V". As they aged they would often crack and break up due to the flexing so there was a bit of a redesign where they relieved the inside of the "V" to reduce this problem. Many people think that this kind of belt drives by engaging like a chain does, but no, it's only a design improvement to enable longer belt life. Here's one of each type:

P1080302.JPG

P1080301.JPG

Later models and just about everything I can think of today, use "multi V" belts. This is the one that came off Becky when I did her Cam belt (I would always do a fan belt at the same time):

P1080298.JPG

Looking at the inside you can easily see the difference to the old belts:

P1080299.JPG

These types of belt transmit drive on the sides of the "V" So you can see, it's obvious that the "multi V" design can transmit a lot more torque before it will slip. Alternators now a days have to provide much more electricity than in the past (just think of all the electrical/electronic "stuff" on modern cars and it takes a lot of effort to drive them. Now you know how it transmits drive it's worth being aware, when checking these, that apart from looking for obvious physical damage to the belt look also to see if the belt is seated so far into the pulley that it is touching the bottom of the "V". Often this will be easy to see from the "witness marking" on the pulleys. If the pulley sides are polished right down to the bottom of the "V" then the belt is bottoming out and, even if it looks almost new (someone may have fitted the wrong belt) it's not going to transmit drive properly. Rather more difficult to see on the "multi V" set up but still possible. Because the belt transmits drive on the sides of the "V" it's the sides which wear and as it does so the belt will drop deeper into the "V" until the inner diameter of the belt bottoms out in the pulley. Once it does that the sides of the belt can no longer grip the "V" sides of the pulley and it will slip!

Timing belts are synchronous belts and drive using molded in "teeth" - as you can see here on Becky's old one:

P1080300.JPG

Generally speaking it's not all that not easy to tell if they are about to "GO". You might be lucky and catch one just as the teeth start to crack up at the base of the tooth form or witness some other defect. In my experience though they look serviceable until the day they suddenly go "bang" usually with virtually no warning. If you've just bought a car and are checking the belt, if it still has the writing clearly visible on the smooth side then I would feel happy it had been changed probably within the last one to two years. If the writing has virtually worn off I'd be doing a belt on it asap. From then on I would follow the manufacturer's recommended interval.
 
The Punto HGT cam belt that let me down (or more accurately the one I stupidly chose to drive) was showing cracks between the timing teeth. These were clearly visible where it went around the tensioner. Some stripped away, wrecking the valves.

However (sort of) in my defence, the whole lot was so well hidden it wasn't possible to see the timing belt at all. A big percentage of the job was simply extracting (and replacing) the belt cover.

BUT the flat auxiliary belt was also showing cracks across the V ribs. As these are usually replaced with the timing belt it was likely cracks in one indicated cracks in the other. Cam belts are not worth the risk of taking beyond their service life. Some cost a fortune to replace but its still better than a new engine/car. I wont make that mistake again.
 
Last edited:
Back
Top