Jump to content
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Richard10002

Cambelt or chain? Vetus M4.14

Featured Posts

Motivated by one of Tony’s comments on another thread, “don’t buy an engine with a cambelt, always a timing chain”, I wondered what my Vetus M4.14 has... chain or belt?

 

I’ve had a google and can only find references to the alternator belt... even an exploded diagram I found of the timing system doesn’t show the belt or chain.

 

Any ideas? If it’s a belt, how often should it be changed?

Share this post


Link to post
Share on other sites
10 minutes ago, Richard10002 said:

Motivated by one of Tony’s comments on another thread, “don’t buy an engine with a cambelt, always a timing chain”, I wondered what my Vetus M4.14 has... chain or belt?

 

I’ve had a google and can only find references to the alternator belt... even an exploded diagram I found of the timing system doesn’t show the belt or chain.

 

Any ideas? If it’s a belt, how often should it be changed?

Some VW turbo engined car owners may not agree with that statement. The problem is that the timing chain is much longer and of lighter construction on the OHC engines than on the older OHV engines. The consequence is that they are more prone to stretching, and in the worst cases juming a tooth on the cam cog. Furthermore the cost of replacing a cam chain is almost double that for a cam belt.  The belts fitted to earlier engines were prone to premature failure, prompting the introduction of chains. However, technology has moved on and the new belts are far more reliable, and some manufactures have returned to using belts, particularly in their higher performance engines (they are also a lot quieter.)

Share this post


Link to post
Share on other sites
Just now, David Schweizer said:

Some VW turbo engined car owners may not agree with that statement. The problem is that the timing chain is much longer and of lighter construction on the OHC engines than on the older OHV engines. The consequence is that they are more prone to stretching, and in the worst cases juming a tooth on the cam cog. Furthermore the cost of replacing a cam chain is almost double that for a cam belt.  The belts fitted to earlier engines were prone to premature failure, prompting the introduction of chains. However, technology has moved on and the new belts are far more reliable, and some manufactures have returned to using belts, particularly in their higher performance engines (they are also a lot quieter.)

 

But we are talking about engines in boats and even one of those VW engines would probably be far more reliable than a cam belt one. They are sealed inside the engine so and lubricated so no segregation caused by oil/fuel contamination and virtually no chance of the chain rusting to the sprockets. Also no chance of a change down into third at 70 mph giving the chain a snatch with trying to accelerate the camshaft to keep pace with the crankshaft.

 

Now, if you are willing to personally offer a 30 year guarantee against belt failure when change intervals are ignored and while in inland boat use I just might agree a belt is better but until then no, a chain on those few inland boat engines that use then is a far less failure prone item. The vast majority of inland boat engines use gears. The only common ones I know of that use chains are the BMCs and those are twin chains or triplex chains on the 2.2 and above.

 

Anyway, a manufacturer who states an 80,000 mile belt change interval at the point of sale and nthen changes it to 40,000 or every four years once the purchase is complete is not one confident in the technology.

 

 

Share this post


Link to post
Share on other sites
28 minutes ago, Tony Brooks said:

 

But we are talking about engines in boats and even one of those VW engines would probably be far more reliable than a cam belt one. They are sealed inside the engine so and lubricated so no segregation caused by oil/fuel contamination and virtually no chance of the chain rusting to the sprockets. Also no chance of a change down into third at 70 mph giving the chain a snatch with trying to accelerate the camshaft to keep pace with the crankshaft.

 

Now, if you are willing to personally offer a 30 year guarantee against belt failure when change intervals are ignored and while in inland boat use I just might agree a belt is better but until then no, a chain on those few inland boat engines that use then is a far less failure prone item. The vast majority of inland boat engines use gears. The only common ones I know of that use chains are the BMCs and those are twin chains or triplex chains on the 2.2 and above.

 

Anyway, a manufacturer who states an 80,000 mile belt change interval at the point of sale and nthen changes it to 40,000 or every four years once the purchase is complete is not one confident in the technology.

 

 

 

Thanks for the explanation Tony, I was not aware that most boat engines use gears rather than chains, which would be much more reliable than a belt or chain.  I am only familiar with the BMC 1.5 OHV engine, which has a very robust chain, which is far shorter than the much lighter an longer chain on VW turbo petrol OHC engines, with which I am also familiar.

 

With regard to belt change intervals, my garage explained to me that deciding when to change a belt is a bit of a black art, and needs to take into account driving style and environment. They suggested that my driving regime of mainly low speed local journeys in light traffic would permit a longer interval, but that someone who drove on a lot of journeys at speed with numerous gear changes, and long idling periods in traffic would need to change the belt close to the lower mileage. They suggested that the mileage figure is a poor indicator and that using engine hours (as on a boat) would be far more reliable.

Edited by David Schweizer

Share this post


Link to post
Share on other sites
1 hour ago, Tony Brooks said:

 

 

 

Anyway, a manufacturer who states an 80,000 mile belt change interval at the point of sale and nthen changes it to 40,000 or every four years once the purchase is complete is not one confident in the technology.

 

 

That would be about 1000 hrs then

Share this post


Link to post
Share on other sites
53 minutes ago, David Schweizer said:

With regard to belt change intervals, my garage explained to me that deciding when to change a belt is a bit of a black art, and needs to take into account driving style and environment.

The point remains that a cambelt change is routine servicing (on a car) and should not be neglected. It is false economy to stretch the interval (see what i did there?). A change of water pump at the same time is also a good idea.

I understand that on certain models of German car fitted with a timing chain, it cannot be replaced without taking the engine out. Bit of a bugger if you have to do something four times less often but it costs well over four times more to do it.

Share this post


Link to post
Share on other sites
1 minute ago, Machpoint005 said:

The point remains that a cambelt change is routine servicing (on a car) and should not be neglected. It is false economy to stretch the interval (see what i did there?). A change of water pump at the same time is also a good idea.

I understand that on certain models of German car fitted with a timing chain, it cannot be replaced without taking the engine out. Bit of a bugger if you have to do something four times less often but it costs well over four times more to do it.

 Especially for the garages profit.  We used to get 12,000 miles  plus out of a carbon ring seal water pump yet today they recommend with the cam belt. So much for advances in technology!

Share this post


Link to post
Share on other sites
41 minutes ago, Tony Brooks said:

I agree, but every four years?

 

It depends on how many miles you do. With my annual mileage and my type of driving, it would be every 15 to 20 years

Share this post


Link to post
Share on other sites
44 minutes ago, David Schweizer said:

 

It depends on how many miles you do. With my annual mileage and my type of driving, it would be every 15 to 20 years

No because they would do it when they change the belt, 4 years so a lot less miles. Our service is due every year or 12000 miles it actually gets serviced at about 8 to 9000 miles because that is all we do in a year.

Share this post


Link to post
Share on other sites
Just now, ditchcrawler said:

Our service is due every year or 12000 miles

A lot of car drivers/owners don't realise it's "whichever comes first".  The Memsahib has a four-year-old car (bought new) with about 7000 miles on it. AFAICR it is still on its original cambelt.

Share this post


Link to post
Share on other sites
1 minute ago, Machpoint005 said:

A lot of car drivers/owners don't realise it's "whichever comes first".  The Memsahib has a four-year-old car (bought new) with about 7000 miles on it. AFAICR it is still on its original cambelt.

I had the same discussion with a boater who changed his oil one every three years as the service schedule said annually or at XXX running hour, so he chose the running hours.

  • Haha 1

Share this post


Link to post
Share on other sites
16 minutes ago, ditchcrawler said:

No because they would do it when they change the belt, 4 years so a lot less miles. Our service is due every year or 12000 miles it actually gets serviced at about 8 to 9000 miles because that is all we do in a year.

 

Both Jan and I have driven VW Audi (petrol not diesel) cars for nearly forty years, and have never changed the cam belt every four years, unless tha mileage dictated it be done. We have always been guided by somewhere between the lower and upper mileage figure. We never had one fail.

 

Edited by David Schweizer

Share this post


Link to post
Share on other sites
43 minutes ago, David Schweizer said:

 

Both Jan and I have driven VW Audi (petrol not diesel) cars for nearly forty years, and have never changed the cam belt every four years, unless tha mileage dictated it be done. We have always been guided by somewhere between the lower and upper mileage figure. We never had one fail.

 

There is at least a chance that the petrol engines will be "safe" in that if a belt brakes the valves will not hit a piston so all you risk is the inconvenience of recovery and repair. I don't think I know of a "safe" diesel and as belt drives are usually on cars and light vans where performance  has some importance (in many customers' eyes) the moving parts are likely to be made a slight as possible so a piston hitting a valve will do lots of damage. Diesel engines in cars really should not be equated to diesel engines in boats.

1 hour ago, David Schweizer said:

 

It depends on how many miles you do. With my annual mileage and my type of driving, it would be every 15 to 20 years

As aid above, the words are WHICHEVER COMES SOONER. Ignoring that increases the risk of a very expensive failure. With such a low mileage I suspect you have a petrol car and many petrol engines will suffer no damage if the belt snaps, they just stop.

Share this post


Link to post
Share on other sites

Done several millions of miles in many Citroen PSA diesels.

Only had one belt let go, my fault, thrashed it too hard, too old, too long.

Never changed cam belts to any mileage or age though none would have been older than 8 years.

Inspected them at every 5K miles service. Checked that the writing could still be seen on the back and that no tooth cracking apparent, checked tension and left alone if all OK.

Never changed a water pump or a tensioner bearing. Most of these vans did 400K miles plus.

 

But in the bowels of a boat is a different story, would not have a belt driven OHC engine in one.

 

When these rubber bands first appeared in the UK on Vauxhall Victors they were warranted for the life of the vehicle, that very quickly changed.

We had hundreds let go due to cam seizing on start up before oil pressure built up. Having the oil filter at the top of the engine didn't help!

Share this post


Link to post
Share on other sites
47 minutes ago, Tony Brooks said:

many petrol engines will suffer no damage if the belt snaps, they just stop.

Yup, I had a Mondeo that did that. 

Share this post


Link to post
Share on other sites

The service schedule for my Lombardini 1404 cam belt change states every 2500 hours. When mine was changed at precisely this (a very straight forward job as the access was good) you could not visibly distinguish between the old and the new one.

Share this post


Link to post
Share on other sites
25 minutes ago, WotEver said:

Yup, I had a Mondeo that did that. 

 

23 minutes ago, rgreg said:

The service schedule for my Lombardini 1404 cam belt change states every 2500 hours. When mine was changed at precisely this (a very straight forward job as the access was good) you could not visibly distinguish between the old and the new one.

Diesels stop very quickly, and noisily!

 

That's precisely why we inspected them rather than waste money. Saved time too when you are servicing many high mileage vehicles every 2 weeks.

Share this post


Link to post
Share on other sites
6 hours ago, Stilllearning said:

Think these engines have pushrods, so no belt just a timing chain inside the front engine cover?

Pushrods only operate the valves in a OHV motor with mid motor height cam shaft you still have to have a connection twixt crank & cam shaft either gear or chain drive for ohv or the same +belt for O HC (over head camshaft ) suspect the op's motor would be gear

Edited by X Alan W

Share this post


Link to post
Share on other sites
2 hours ago, Tony Brooks said:

There is at least a chance that the petrol engines will be "safe" in that if a belt brakes the valves will not hit a piston so all you risk is the inconvenience of recovery and repair. I don't think I know of a "safe" diesel and as belt drives are usually on cars and light vans where performance  has some importance (in many customers' eyes) the moving parts are likely to be made a slight as possible so a piston hitting a valve will do lots of damage. Diesel engines in cars really should not be equated to diesel engines in boats.

As aid above, the words are WHICHEVER COMES SOONER. Ignoring that increases the risk of a very expensive failure. With such a low mileage I suspect you have a petrol car and many petrol engines will suffer no damage if the belt snaps, they just stop.

 

I didn't change the belt on my first Passat until after the (then) recommended 80,000 miles, my garage then suggested that I changed the belt on the next two at 60,000 miles, and then on my fourth Passat it had been reduced to 40,000, but apparently this had very little to do with the belt but the belt tensioner, which had been changed from metal to plastic, and it simply wore out. As there is almost the same amount of labour involved with a tensioner change as there is with a belt change, it was sensible to change the belt at the same time. By the time I got my last Passat,  the tensioner had been re-designed and was made of metal, so the belt change interval was longer, and I got it changed at 78,000 miles. Unfortunately not long after the new cam belt had been fitted, the car was written of by a careless "White Van Man", by which time VW were no longer importing petrol Passats, so I got a Golf 1.4TSI estate (as rare as hen's teeth!) which is very economical and very lively, but it isn't a Passat!😢😢

Share this post


Link to post
Share on other sites

I do wonder if frequent cambelt changing is a "rip off Britain" thing. 

 

I had a 2005 Ford Focus 2.0 diesel, and the recommended cambelt change interval was 10 years or 100,000 miles. It got to 100,000 without an issue.

 

My current VAG 2.0 diesel requires a cambelt change every 5 years or 140,000 miles according to VAG UK, but a German friend has an identical engine in his car and VAG Germany say 10 years or 100,000 miles.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.