A question re: car engines/timing belts

NIMAN

Sorry if its a stupid question.

Cars have timing belts, that need changed.
Some cars have timing chains which afaik don't need to be replaced.

So why aren't all cars made with chains?

Lellostag

LIGHTNING wrote: »

Chains are louder, heavier, more expensive, more complicated and if they need replacing costs a shed load more to fix.

Exactly, and stretching timing chains aren't unheard of either, although probably not a big problem nowadays.

JohnBoy26

NIMAN wrote: »

Sorry if its a stupid question.

Cars have timing belts, that need changed.
Some cars have timing chains which afaik don't need to be replaced.

So why aren't all cars made with chains?

Tell that to any n16 almera owner out there, or anyone with an early diesel accord. You can also include anyone with a twin charged 1.4 petrol vw or 1.2 polo from the early-mid 00's

Special Circumstances

JohnBoy26 wrote: »

Tell that to any n16 almera owner out there, or anyone with an early diesel accord. You can also include anyone with a twin charged 1.4 petrol vw or 1.2 polo from the early-mid 00's

Bee emmm diddle you x20d can be added to the list.

JohnBoy26

Special Circumstances wrote: »

Bee emmm diddle you x20d can be added to the list.

Indeed! :eek:

Lellostag

LIGHTNING wrote: »

Tell that to my mate who had to get his Honda S2000 chain replaced. That was pricey.

Well, thats a bit of a bummer, didn't think it was a problem on such modern cars, really. I know some older 70s and 80s engines suffered from stretching chains, particularly the ones with a simplex chain.

gctest50

Lellostag wrote: »

Well, thats a bit of a bummer, didn't think it was a problem on such modern cars, really. I know some older 70s and 80s engines suffered from stretching chains, particularly the ones with a simplex chain.

BMtroubleU : £4475 (sterling)

.... and it's at the back of the engine anyway ( so the front of the bonnet can be low and pedestrian friendly )

vandriver

My wife's Fabia needs a new chain.The same place that did my timing belt for €300 is looking for €700 for the chain.
Btw,is that a good price?

projectgtr

LIGHTNING wrote: »

Tell that to my mate who had to get his Honda S2000 chain replaced. That was pricey.

Is that a common problem with the S2000`s F20c ?

biko

vandriver wrote: »

My wife's Fabia needs a new chain.The same place that did my timing belt for €300 is looking for €700 for the chain.
Btw,is that a good price?

Are you sure it has a chain? What year and model is it?

Lellostag

gctest50 wrote: »

BMtroubleU : £4475 (sterling)

.... and it's at the back of the engine anyway ( so the front of the bonnet can be low and pedestrian friendly )

Ah yeah, I remember now having read about the N47 engine issues. Not much technological evolution since the 1970s Triumph Stag then it seems, at least not regarding the chain setup and quality...

vandriver

Its an 07 1.2 htp

Seweryn

Lellostag wrote: »

Well, thats a bit of a bummer, didn't think it was a problem on such modern cars, really. I know some older 70s and 80s engines suffered from stretching chains, particularly the ones with a simplex chain.

The chain wear was less of a problem in '70 and '80 designs than recently.
At the time some manufacturers, like Mercedes-Benz were only making engines with chain driven camshafts.

Lellostag

Seweryn wrote: »

The chain wear was less of a problem in '70 and '80 designs than recently.
At the time some manufacturers, like Mercedes-Benz were only making engines with chain driven camshafts.

This reminds me, doesn't Fiat's twinair engine use the engine oil as chain (belt?) tensioner, leading to failures due to too long oil change intervals? I might be wrong, but seem to remember having read about that somewhere...

Special Circumstances

Lellostag wrote: »

This reminds me, doesn't Fiat's twinair engine use the engine oil as chain (belt?) tensioner, leading to failures due to too long oil change intervals? I might be wrong, but seem to remember having read about that somewhere...

Many engines use oil pressure to keep tension on the chain. Some are very reliable, like the brazilian made engine in the first gen minis. Some are disastrously engineered and will skip teeth if you look at them the wrong way, like the french/german Prince engine in the second gen minis.

Lellostag

Special Circumstances wrote: »

Many engines use oil pressure to keep tension on the chain. Some are very reliable, like the brazilian made engine in the first gen minis. Some are disastrously engineered and will skip teeth if you look at them the wrong way, like the french/german Prince engine in the second gen minis.

Thanks SC, I wasn't aware that was such a common solution nowadays. Goes to show how stuck I'm in the "good old days", eh?!

Perhaps the biggest problem nowadays is our extremely high expectations of our cars reliability, long gone are the days when engines needed full rebuilds well before hitting 100k miles...

Seweryn

Lellostag wrote: »

Perhaps the biggest problem nowadays is our extremely high expectations of our cars reliability, long gone are the days when engines needed full rebuilds well before hitting 100k miles...

Yeah, and at the same time the new engines do not reach mileages we used to get from quality older cars. A couple of my friends covered over 1 mln km in their cars without engine (or cam chain) problems.

John T Carroll

Special Circumstances wrote: »

Many engines use oil pressure to keep tension on the chain. Some are very reliable, like the brazilian made engine in the first gen minis. Some are disastrously engineered and will skip teeth if you look at them the wrong way, like the french/german Prince engine in the second gen minis.

The twin charger VW 1.4 TSI engine (now discontinued?) chains were prone to stretching, the hydraulic tensioner does its job and gets fully extended and trouble follows. Here are two pictures, courtesy of a George Dalton post that graphically illustrates the problem but I don't think that we should return to the old gear driven push rod engines.

Lellostag

Seweryn wrote: »

Yeah, and at the same time the new engines do not reach mileages we used to get from quality older cars. A couple of my friends covered over 1 mln km in their cars without engine (or cam chain) problems.

Yeah, it is a bit ironic really, isn't it? I wonder whether perhaps the late 80s and early 90s essentially hit the sweet spot in terms of reliability and general efficiency, ie not too complicated to make them fragile again and not too thirsty either to make them somewhat economical to run... What I mean is manufacturing quality had improved significantly since the 70s while emissions requirements still hadn't affected the overall engine designs too much.

Seweryn

Lellostag wrote: »

Yeah, it is a bit ironic really, isn't it? I wonder whether perhaps the late 80s and early 90s essentially hit the sweet spot in terms of reliability and general efficiency, ie not too complicated to make them fragile again and not too thirsty either to make them somewhat economical to run...

True. Especially the reliability / longevity of some engines that were in production at that time hit the peak.

Surely, the newer engines are more powerful and with the DPF filters, EGR valves, high pressure injection systems, etc. that are unreliable and very expensive to repair are "cleaner to the environment" (well, only at the exhaust pipe, but that is another story).

wendell borton

Lellostag wrote: »

Yeah, it is a bit ironic really, isn't it? I wonder whether perhaps the late 80s and early 90s essentially hit the sweet spot in terms of reliability and general efficiency, ie not too complicated to make them fragile again and not too thirsty either to make them somewhat economical to run... What I mean is manufacturing quality had improved significantly since the 70s while emissions requirements still hadn't affected the overall engine designs too much.

The Austin A-series engine was designed in the early fifties and was in production until 2000.

ofcork

Afaik most mercedes need their chains replaced around the 80k mark which is crazy really.

wonski

ofcork wrote: »

Afaik most mercedes need their chains replaced around the 80k mark which is crazy really.

Checked every 80k maybe, not changed?

Lellostag

LIGHTNING wrote: »

Sorry but serious rose tinted glasses going on here. Modern engines are so much cleaner,fuel efficient and powerful to those from the 80/90's. You want everybody to be driving around with air-cooled pushrod engines? I have had many a cars from the 80's and they can be a real nightmare engine wise.

Not surprisingly you are completely missing my point; Modern engines are obviously much more efficient, frugal and powerful, that's not in question. My point is that all this evolution to squeeze more out of the engines while substantially improving fuel economy and emissions has also introduced many weak points that never existed before. In other words modern engines have so many more things that can go wrong, and will unless a very strict maintenance regime is adhered to.

There are plenty of early 90s engines which will do 500k miles without too much trouble while only needing normal levels of maintenance.

No doubt modern engines would be even better if they weren't so loaded with emissions and fuel economy solutions.

Voodoomelon

In fairness, relative to the number of chain driven engines out there, very few have issues and virtually all will last the lifetime of the car. Belts are more of a pain in the ass in my book, usually requiring changing twice over 120k miles.

John T Carroll

Voodoomelon wrote: »

In fairness, relative to the number of chain driven engines out there, very few have issues and virtually all will last the lifetime of the car. Belts are more of a pain in the ass in my book, usually requiring changing twice over 120k miles.

Would agree, single charger 2008 Passat 1.4 TSI in my family has 188.6 K Kms up from new with no issues.