Reading several threads reently on cambelts gets me thinking..... with a low annual mileage, about 6000, and recommended belt change at 4 years or 40,000 miles, is it realy necessary? How long could I go before changing the belt - not really stretching things (no pun intended) but as the cost of changing one is going to be over £300 (ouch) and this is about the total I would usually pay for 2 years of maintenance, it seems an excessive cost for a part that would not appear to wear unduly.
Now, if some belts can be lifed at 72,000 miles or more, would I be reasonably safe to go for, say 6 years and 36,000 miles before changing? Car is garaged at night, so no frost damage or excessive condensation to worry about. What is/are the time-related factor(s) to consider?
Any thoughts?
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Cambelts aren't changed because they wear out, they're changed because IF they break they cause a lot of expensive damage. Ignore the manufacturers recommendation, at your own peril (and expense).
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£300 belt change? What car you got????
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£300 must be the main dealer price I guess...
Experienced people on this site strongly recommend regular cambelt changes, at at least the frequency specified by the manufacturer (and some of those have chaged since the manual was published...)
When I spoke to a local independent (Ford specialist - and he DOES seem good) he thought 40k was too soon for a Focus belt.
But given the potential damage of leaving it a little longer, I am going to go with HJs regulars and get it done. At the end of the day it's all part of the running costs, and I'd sooner pay a known amount than suffer a huge unexpected expense (and inconvenience) due to cambelt breakage (see the current Modeo thread...)
It's your choice really, if you choose to take the risk you may be quids in...or out...
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It's not only the mileage that will deteriorate a cambelt. Heat, cold, & general polution will also attack the rubber. That is why manufacturers recommend either mileage or age for the belt interval change.
As for "the cost of changing one is going to be over £300"; that is a lot cheaper than having to replace the engine should it let go. There are some things that you can get away without changing at service time, plugs or an air filter for instance, but don't neglect the cambelt. There are plenty of other threads relating to cambelt failures, some because people thought they could get away without changing it. Don't become another Backroom statistic.
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Is it an interference engine - ie can the valves hit the piston if the cam stops?
Can't be that difficult to do it yourself, surely? Then it only costs the price of a belt - £30 max?
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Thanks for feedback so far but I still don't see any technical info relating to deterioration with time.
2 cars in family: Renault scenic and Ford Galaxy, both with 1.9 turbodiesel engines. On both, the job involves removing one or more engine mounts, apparently, and this is why the cost is so exhorbitant. Local garage also quoted similar amount and said it would probably take them longer than main dealers as they don't do many cambelt changes on these vehicles. Engine-mount removal means that it's out of my DIY skills-range and I don't have the equipment to support the engine (hoist needed? bonnet removal?)
Previous car I had was a Honda petrol engine with very long cambelt change on mileage, and from memory no time-related change. Had belt changed after about 4 years and mechanic told me that the old belt looked "as new" and probably didn't need changing. Left it for about another 6 years before changing it again, then left that replacement on for about 7 years and sold the car with it on.
So do I really need to keep my fingers crossed if I want to get 6 or 7 years' life out of cambelt on present cars?
Incidentally my parents' car is 8 years old and on original cambelt at 54,000; change not due by mileage yet and again no guidance offered on time - except their local mechanic suggests that they get it changed soon!
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IET - one dilemma is that a belt is usually a bit inaccessible, so if you say 'check the belt' answer is usually 'if we check it, may as well change it'. So many people toss a coin and say 'it'll probably do another 6 months', and usually it does. When it fails, preventive maintenance suddenly looks like a good idea, despite the cost.
The rail network is going through a serious bout of that kind of thinking, I suspect.
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My wife has a Peugeot 106 diesel.. 9 years old and 40k miles from new. In theory it should now have a new cambelt but had one after 5 years - only 25k miles.
The reasons were obvious - it was relatively cheap at £110. The cost of a new engine is £00s or £000s.
Some makers have very good quality cambelts - Ford and most Japanese makes are noted for the quality of their rubber based parts.
Based on my experience of French and German manufacturers I would replace all moving belts at 5 years or 50 k miles whichever comes soonest. (and that includes Vauxhall, BMW and especially VW/Audi.
After 4 years most alternator drive belts are getting tired.. and belt tensioners fail..
If very expensive as you suggest, why save £500 when you can buy a new engine for only £5,000? :-)
madf
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If I had the money I would get the work done every 3 or 4 years as per manufacturers' recommendations! I don't have the money and am therefore trying to cut out things that I think are unnecessary - with some mechanical knowledge (BSc in Engineering, and I am a "practical" person) I'm trying to get advice on which I can make a considered judgement.
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IET,
Manufacturers (i.e. VX) have changed the life expectancy on empirical evidence, and there is plenty of that here. Consider the advice given as practical, and change at no more than the stated maximum for your engine. Be aware that the nearer to that maximum you get, the greater the risk of failure. Even new belts run the risk of infant mortality, whether through faulty materials or workmanship. The maxim 'if it aint broke don't fix it' only works on none maintenance items. Belts don't count.
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IET:.. What is/are the time-related factor(s) to consider? .. >>
The rubber is likely to deteriorate over time based on the environment (chemical + physical) that it is exposed to.
... am therefore trying to cut out things that I think are unnecessary - with some mechanical knowledge (BSc in Engineering, and I am a "practical" person) ... >>
As a qualified Engineer, you will know the concept of MeanTimeToFailure(MTTF) and will understand that the manufacturers initially based their predictions on belt-life on a combinationation of Theory and Lab Tests. When empirical evidence showed that the failure rate was higher/earlier than expected, the affected manufacturers alterd their recommended change periods. To be on the safe side, the normal practice should be to set a change interval long before the new empirical MTTF. Your particular car (given its usage pattern) might exceed the new MTTF by a long period; on the other hand, you might be unlucky and have a failure in the next mile!
As your problem arises from a lack of funds, perhaps you should consider Insurance as a way out. You may wish to look at the following options to see if they are suitable for you:
www.aamembership.co.uk/breakdowncover/join/parts_l...p
www.theaa.com/services/mot_insurance.html
www.motoreasy.net
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IET:
postscript - Many contributors here are practical mechanics with day to day real experience of broken cambelts.
Thier advice is just as invaluable as going to a forum to ask a Heart Transplant Surgeon "when is the best time to get a new heart or do I need a new heart at all?" - to give a considered reply, he/she would need to examine you and (enter all the caveats you can think of).
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IET,
Take your point that you are being prudent about maintenance, and eMBe makes a valid point about the statistical likelihood of the belt breaking. Everyone would agree that you (all of us) want to get the belt changed before it breaks.
Also accept that the 'time based' reasons for changing the belt are quite wooly - 'emissions / temperature / ..'. I fear that the reality is these are not well known, but my assesment of the discussion is that time and mileage are both factors; you ultimately must weigh up what your personal "risk:reward" preference is.
My only other comment is that my father (aged 67) does all the maintenance on his S plate Mondeo himself. He always runs cars until my mother says they are too scruffy (!) and always works on them himself. This year, at 47,000 on the clock and five years of age, he paid someone to change the cambelt. His view was that he had pushed it as far as was 'reasonable'. Even for him - never one to waste his cash - he thought the risk at this point was worth the cost of replacing the cambelt.
All the best
Jono
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Last year, for the missus to drive as her first car and not have to worry too much, I purchased a nine year old Pug 306 1.8 Sedan, with genuine fourteen something thousand miles from new, and in amazing nick. (MOT guy called all his mates to come and oggle earlier this year!)
Despite the extreme low mileage, and total absence of any oil weeps to contaminate the belt when I removed the timing belt cover, I decided to replace the belt.
I am glad I did.
The rubber had started to perish, and many teeth were torn at their root, just waiting to become fully detached...
£137.02 for parts and labour (I was having a lazy moment!) well spent.
Over a year on, I'm still amazed how £2601 purchased a car totally devoid of grandeur, but which is totally reliable and can be such fun to drive. It's a hoot. The thing's a veritable Tardis inside, too, especially rear passenger leg room, and boot. Just a bit short from seat squab to roof lining, as I find applies to so many cars these days.
(Tip: the £1 is what secured the car for me in a blind auction of the deceased former owner's estate! "Never bid round numbers" was Dad's advice, and how right he was.)
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Ah, this is getting more interesting and helpful now. I am fully aware of the concept of MTTF and MTBF, but the cynical side of me also says that manufacturers and dealers want to take more of my money from servicing since that they have reduced margins from new vehicle sales. For instance, how can they justify charging £70 or £80 per hour for labour when the poor bloke doing the job would be lucky to get £15 per hour?
Anyway, looks like I'll use the credit card next year to get a cambelt change done.
Now why do manufacturers design the engine installations in such a way that so much labour is required to perform a change? (or maybe that's for a whole new thread).
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I'm trying to get advice on which I can make a considered judgement. It is the considered judgement of all those who contribute here that it simply isn't worth the risk to 'stretch' the belt change interval. Remember: the DFMEA on the Space Shuttle put the risk of fuel tank O ring failure at 1 million to one - the risk was extremely low but what this doesn't tell you is whether it is likely to fail first time or millionth time. The rest is history.
try using a trolley jack to support the engine - no hoist required. I made a simple wooden cradle to put between my jack and the sump.
Now why do manufacturers design the engine installations in such a way that so much labour is required to perform a change? Manufacturers design the installation so it is easy for them to assemble the car in the first place, thus cutting the assembly cost. Most cars will only see one or two belt changes in their lifetime and these will be way out of the warranty period probably. It is unlikely that the first change cost will be bourne by the first owner so therefore the cost of the change does not feature in manufacturers "cost of ownership" considerations. So not the manufacturers problem.
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All this talk of cambelts has reminded me - my mum's Clio (diesel) is 9 years old. It's done 40,000 mies but has never had a belt. I reckon it's about time this was done. The problem is that she only does about 500 miles a year now and keeps the car going on her pension. A belt change on the Clio diesel is said to be expensive. I was wondering how easy it would be to do myself. I've replaced(older)engines and suchlike before but never actually done a belt. Is it quite straightforward? My worry would be getting the teeth out of sync - although I do have a Haynes for the Clio. I'm not bothered about taking off an engine mount and supporting etc - got plenty of good tools.
Anybody got experience of the 1.9 Renault diesel (1994) ?
Any advice gratefully received.
Graeme
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If you are at all unsure, then please leave it to the experts. You will probably need special locking/locating tools; without these the job is very fiddly if not impossible.
My advice? Shop around for quotes.....you might be suprised.
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