Cam belt - a vehicle's Achilles heel?

[Jo May]

Took our camper in today for a cam belt. It's 5 years old and the van has done 'only' 16,000 miles.
It'll cost £600 - 700.
What a horrible, poxy, inadequate, weak link this thing is in a complex vehicle, one that, touch wood has run fine to date.
Of course, £600 would be 'cheap' if it did happen to snap. But it's scant consolation for a piece of kit that is basically not up to the job. I know they have chains now - are these changed periodically?
But whatever, the majority are rubber and integral to the just about every vehicle. You'd think that by now they'd have come up with a better system than something that needs to be changed after so little mileage?

I ponder this conundrum, and resultant hit to the wallet, on my 3-mile walk home having dropped the van off. It's a walk I normally thoroughly enjoy along the canal towpath. But my mood is rather dark, summed up when my tracky bottoms are muddied by two passing dogs that jump up - 'he's only playing', said one owner, 'sorry, he's just learning,' said the other. Learning?!
To put the tin lid on it, as it were, I got soiled by a passing duck as it crapped on my anorak!

Ruddy cam belts.

 

[Coolcats]

Chains don’t stretch, the pins could possibly wear.
Wet belts, why would you.

Are you sure about that? Bicycles have chains and they stretch, you can get a gauge to tell you by how much and whilst it may be pins and thier holes that elongate it’s those elements that make a chain.

CC-4 Chain Checker

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[tonyidle]

Ford used to do an engine with neither a cam belt or chain, I think it was the Essex V6 iirc.
The cams were driven by a gear cog.

Which used to lose it's teeth on occasion.

 

[Dolmen]

I appreciate every one has a different risk profile so I am not advocating this, however, I wouldn't even dream of changing a cam belt at 5 years with only 16,000 miles on the clock. I know many will say it is age not mileage and many will point to horror stories of not changing, so just saying what I would not do, not recommending anything to anyone.

 

[68c]

What's wrong with push rods. My Moto Guzzi revs to 8,000 rpm with push rods so not a problem for a diesel. Push rods can enable valves to be set at angle for peak efficiency. The cam can be gear driven or driven with a shorter chain.

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[dunnah01]

Ford used to do an engine with neither a cam belt or chain, I think it was the Essex V6 iirc.
The cams were driven by a gear cog.

I had a Sierra Janspeed XR4i Turbo back in the day with a V6 Cologne engine that used the gear driven cam. Absolute hooligan ..

 

[ivorantony]

Ford used to do an engine with neither a cam belt or chain, I think it was the Essex V6 iirc.
The cams were driven by a gear cog.

Indeed they did, But the fibre gear would strip it’s teeth so still leave you stranded,
But worse is the hexagonal drive shaft to the oil pump failing, oil light comes on,
Driver ignores it the you have one seized engine,
So old wasn’t always best,

 

[meanders]

Which used to lose it's teeth on occasion.

The early ones had fibre cogs. They were later replaced with nylon that was better but still failed occassionaly. In the same timescales, the 1600E gearbox was initallily fitted with some nylon gears that would strip under some circumstances. I think Ford gave up experimenting with nylon after that.

 

[PaulW2]

I appreciate every one has a different risk profile so I am not advocating this, however, I wouldn't even dream of changing a cam belt at 5 years with only 16,000 miles on the clock. I know many will say it is age not mileage and many will point to horror stories of not changing, so just saying what I would not do, not recommending anything to anyone.

This is a slightly different angle, but I was travelling through France recently and wanted to top up my LPG.

So fitted the little dish to my external filler, attached the nozzle and ... all hell broke loose.

I hadn't even started anything, but the gas in the garage's hose was under pressure. This caused an eruption for maybe a minute or two, during which the handle also wouldn't budge (!) so I couldn't stop it.

Once it had all settled I put everything back in order, to discover that the little rubber o ring on the dish had cracked and that this let the gas escape.

Changed the o ring and all was good on my second (nervous) attempt.

The (low mileage) o ring had simply perished due to age. Today I fitted a newly purchased set of o rings to all my adaptors.

I think I won't be taking chances on an old cam belt.

 

[Dave and Jen]

Why does it need all that for the auxiliary belt snapping?

Hmmm I was thinking that too-
Cheers, Dave
Ah have seen the reply.
I once had a Plymouth Barracuda (v8 )
One day it just wouldn't start.
Eventually found that the timing chain had "jumped" a tooth on the sprocket.
Replaced it with a new one and it ran better than it did before .
No idea what the mileage was, it's a long time ago!
Cheers, Dave

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[Grummyb]

apparently its good luck if a bird poos on your car but im not sure if that works for anoraks aswel

 

[headlight]

Which used to lose it's teeth on occasion.

Once they swapped from the original nylon toothed cog to a metal cog, stainless steel normally, I think they were pretty reliable.

 

[meanders]

I think you will find it's only lucky if it poops on your head.

 

[tonyidle]

Once they swapped from the original nylon toothed cog to a metal cog, stainless steel normally, I think they were pretty reliable.

Ford only went to nylon. Aftermarket timing wheels were available in steel (noisy) or aluminium.

 

[meanders]

Once they swapped from the original nylon toothed cog to a metal cog, stainless steel normally, I think they were pretty reliable.

I think you will find it was an aftermarket upgrade, often using aluminium alloys. IIRC the very latest builds had steel with nylon teeth. That followed on from the original fibre ones, then the all nylon.

Edit. tonyidle types faster than me!

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[headlight]

Ford only went to nylon. Aftermarket timing wheels were available in steel (noisy) or aluminium.

Yes sorry I didn't mean Ford swapped to metal but owners fitted stainless or ally cogs which proved to be far more reliable.
Back in the day, a long time ago, I used to rally and I knew a couple of people who rallied V6 Ford's and I can't remember any of them having the cams drive cog fail (plenty of other problems though lol). Just seemed to me at the time to be a better answer than belts or chains.
Although I've never had a cam belt or cam chain fail touch wood.

 

[SVMC15]

Took our camper in today for a cam belt. It's 5 years old and the van has done 'only' 16,000 miles.
It'll cost £600 - 700.
What a horrible, poxy, inadequate, weak link this thing is in a complex vehicle, one that, touch wood has run fine to date.
Of course, £600 would be 'cheap' if it did happen to snap. But it's scant consolation for a piece of kit that is basically not up to the job. I know they have chains now - are these changed periodically?
But whatever, the majority are rubber and integral to the just about every vehicle. You'd think that by now they'd have come up with a better system than something that needs to be changed after so little mileage?

I ponder this conundrum, and resultant hit to the wallet, on my 3-mile walk home having dropped the van off. It's a walk I normally thoroughly enjoy along the canal towpath. But my mood is rather dark, summed up when my tracky bottoms are muddied by two passing dogs that jump up - 'he's only playing', said one owner, 'sorry, he's just learning,' said the other. Learning?!
To put the tin lid on it, as it were, I got soiled by a passing duck as it crapped on my anorak!

Ruddy cam belts.

Yes there are engines that do not have camshafts. I have no experience on car sized engines without them but have sailed with MAN B&W engines that uses actuators to open the valves and inject the fuel.

Not sure why they haven't become mainstream for cars!

 

[Grummyb]

This bit is probably going to be contriversial but why is the OP moaning about having to have the cam belt changed surely he knew that would have to be done when he bought the van.

 

[Bertilak]

So everyone on here believes you should change your rubber tyres at 5 years but not your rubber timing belt... I'm very aware a Golf owner will spend more on belts than tyres...
My wife's 1.4 Citroen didn't have a specified age, so with the approval of the local specialist, had it's original belt at 16years old, but only 90k.

As asides, I remember the early timing belt engines (Ford Pinto and GM J series) were designed with the clearance in the combustion chamber if the belt failed it did no damage. A friend had Cavalier's snap en-route the the Lakes, and he drove in about an hour late...

Obviously you can't do this with diesels, as the combustion chamber is too small.

My complaint is not that they need doing, but they are messy and expensive to do. eg. have the engine mounts bolted on in the middle, the lack space to access all the ancillaries you have to remove first, the need to change all the "lube for life" rollers, including the water pump.

More recently, VW did duck the belt /chain issue with the 5cyl 2.5 engine from all quicker versions of the early T5. This has a massive array of gears instead, but ISTR was considered too thirsty to be the new future for all the crafters too. I'm sure it will have been expensive too. Even these fail if the bearings or seal in the water pump goes, which again is not an easy "planned maintenance" task.

 

[Silver-Fox]

The flip side is our ancillary belt snapped, took the cambelt with it whilst in Spain.

Can I ask how it took the cambelt with it.
Normally they snap and fall on the road.

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[Phill D]

The flip side is our ancillary belt snapped, took the cambelt with it whilst in Spain. Engine out etc €5500 which included a new clutch. £700 I’d snap your hand off. Sit down have a cuppa, all is well!!

what engine was that on? most cambelts are covered , if only by a plastic caseing.

 

[CazPaul]

Every vehicle I buy I ensure it has a chain, Iveco 3 litre Motorhome and Honda Civic 1.8 current car, belts are a can do without expense.

 

[Coolcats]

Of course the other option is buy an EV

 

[DandJ]

I do wonder how many of the cambelt issues with Transits are due to very low mileage and being sat for weeks on end?

 

[Silver-Fox]

We do of course have the improved efficiency of engines with belts, compared to the pre cambelt systems of the 1950s.

I don’t think using a belt has made the engine more efficient from the 50’s some how

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[Neilh]

I understand totally the engineering behind your statement, that the links don't stretch, (although that itself is debatable), but we are talking about the "chain", not it's component parts. If the component parts had worn, but the "chain" is longer than it was when new, then factually the 'chain' has stretched. It hasn't worn longer. That would be an engineering impossibility.

Even so, if you put anything under constant tension it will stretch. You might struggle to measure it, but it's a well known fact of metallurgy, physics and chemistry... Or at least was when I studied.

The chain doesn't stretch, as it doesn't get to it's yield point, so not an impossibility, it could expand with heat!
Chains wear out over time due to a natural process of elongation, commonly referred to as “chain stretch”. While the plates don't actually stretch, the pins and rollers inside the chain wear down with each rotation allowing the plates to sit further apart and increase the overall length of the chain.

I just couldn't let in lie

 

[Silver-Fox]

This bit is probably going to be contriversial but why is the OP moaning about having to have the cam belt changed surely he knew that would have to be done when he bought the van.

Think the op was more upset about the dog jumping up

 

[Silver-Fox]

A friend had Cavalier's snap en-route the the Lakes, and he drove in about an hour late...

Happened to a mate with an SRI, non interference engine.

As you said about a hour to re belt it.

 

[Fdhadi]

Just had my daughters Ford Fiesta 63plate Cambelt changed with 57k on the clock. This is the 1.3ltr engine and not the Ecoboost. A lot don’t realise (me included) that this engine also needs its belt changing after 10yrs or ex amount of miles.

 

[Barchetta47]

Can I ask how it took the cambelt with it.
Normally they snap and fall on the road.

It shredded and pieces caught the cambelt. Well that’s what it looked like. Whatever it was it was a mess.

what engine was that on? most cambelts are covered , if only by a plastic caseing.

It was a 2.8 JTD, although it’s an interference engine it was only the valves that were affected

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[dunnah01]

The chain doesn't stretch, as it doesn't get to it's yield point, so not an impossibility, it could expand with heat!
Chains wear out over time due to a natural process of elongation, commonly referred to as “chain stretch”. While the plates don't actually stretch, the pins and rollers inside the chain wear down with each rotation allowing the plates to sit further apart and increase the overall length of the chain.

I just couldn't let in lie

The pins and rollers are constantly lubricated with the engine oil so there should be negligble wear. The plates will creep over high miles but the weak part is the nylon sliders on the tensioners and guides which wear out fastest even though they are lubricated.