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yoda_me07
2008-12-06, 04:53
so my dad went to get his toyota tarago car serviced.


and his car is around 115 000km.

so i told him to get his belt changed.

he asked the mechanic, and he said that it had a 'timing chain', and didn't need to be replaced.

i googled 'timing chain',
and apparently it will last as long as the engine/car.

is this true?

what im afraid of is the chain will break, and with it the whole engine.

MunkeyQ
2008-12-06, 12:14
You need to check the timing chain for tension and wear to the chain and sprockets, but you do not need to replace it as part of a service routine.

If the chain/sprockets are worn, you then need to replace either one.

MasterYoda210
2008-12-06, 12:17
What he said ^^

Chains are generally used where reliability is a factor. Belts are used where comfort is a factor as belts are a lot quieter than chains. But yeah, generally as long as it all looks good, a chain will last forever man.

Mr Smith
2008-12-06, 13:19
you were under the impression the car had a timing belt...

then you found out it had a chain... which should be fine at 115 xxx.

but still you think your advice is better then the mechanics?


relax, the chains fine, and even if it isn't a broken timing chain isn't the end of the world.

Hung Like Christ
2008-12-06, 17:38
a broken timing chain can mess up your valves royally, to the point that the repair isn't worth it.
Timing chains last quite awhile, but most manuals say to replace them at 80k miles.
I have had 2 fail for me. One on an Oldsmobile V8 and one on a Volvo 240.
Actually, they just stretched too much and jumped a few teeth on the sprocket, thus throwing the timing off so far the car stopped running.
In my case, no valve damage resulted.
Anyway, they do not last forever.

DORITO
2008-12-06, 21:21
a broken timing chain can mess up your valves royally, to the point that the repair isn't worth it.
Timing chains last quite awhile, but most manuals say to replace them at 80k miles.
I have had 2 fail for me. One on an Oldsmobile V8 and one on a Volvo 240.
Actually, they just stretched too much and jumped a few teeth on the sprocket, thus throwing the timing off so far the car stopped running.
In my case, no valve damage resulted.
Anyway, they do not last forever.

Buddy of mine has a crf450 the chain jumped the sprocket and the piston slammed into the valves they broke off and went to work on the cylinder head like it was warm butter. Worst case scenario.

I would say depending on the overall price (labor, parts). If it's relatively cheap, go for it. If not, listen to your mechanic.

Rocko
2008-12-07, 09:08
Timing chains generally last a long time, I'd go for changing one at about 90-100k miles. If you take the front of the engine apart any time before then, it's a good idea to just go ahead and replace it anyway.

Mr Smith
2008-12-07, 09:11
the cars only at 70k miles.

yoda_me07
2008-12-07, 10:44
k thanks guys.

what's weird though is that i looked under the hood, and there was something that resembled more of a timing belt, than a chain.

is there another part of the engine that would resemble this?

im not an expert, just took some basic classes in 'automotive mechanical'

MunkeyQ
2008-12-07, 10:50
k thanks guys.

what's weird though is that i looked under the hood, and there was something that resembled more of a timing belt, than a chain.

is there another part of the engine that would resemble this?

im not an expert, just took some basic classes in 'automotive mechanical'
If you just opened the hood and looked inside and saw a belt, you're probably looking at the fan belt. This drives the alternator, water pump, AC compressor and power steering pump in most cases.

The timing chain is under a sealed, lubricated metal cover on one end of the engine. You can't see it without taking the cover off.

If it had a timing belt, it would also be under a sealed protective cover, although it would not be immersed in oil,

yoda_me07
2008-12-07, 11:25
If you just opened the hood and looked inside and saw a belt, you're probably looking at the fan belt. This drives the alternator, water pump, AC compressor and power steering pump in most cases.

The timing chain is under a sealed, lubricated metal cover on one end of the engine. You can't see it without taking the cover off.

If it had a timing belt, it would also be under a sealed protective cover, although it would not be immersed in oil,

ah there we go =].

at tafe, we just see the engine without the covers.

actually we saw a falcon, with an exposed belt, and the teacher said that was a 'timing belt'.
now it looks like it was a fan belt eh?

or is it that on engines with timing belts, that belt will drive the peripherals as well.

Rocko
2008-12-07, 11:31
Some engines have timing belts that also drive the water pump, but I don't think you see that too often.

MunkeyQ
2008-12-07, 11:37
or is it that on engines with timing belts, that belt will drive the peripherals as well.
The timing belt/chain sometimes drives the oil pump, and on a very few engines, the water pump as well (my old VW had this). Accessories such as the AC compressor and alternator are pretty much always driven from the fan belt though.

yoda_me07
2008-12-07, 11:38
http://forums.justcommodores.com.au/attachments/parts-sale/1158d1106387310-wrecking-vn-commodore-brisbane-engine-bay.jpg
that would be a fan belt right?

Rocko
2008-12-07, 11:42
Yeah, that's a fan belt, also called a serpentine belt because pretty much everything has electric fans now.

MunkeyQ
2008-12-07, 11:48
Yeah, that's a fan belt, also called a serpentine belt because pretty much everything has electric fans now.
Be traditional dammit! It's a fan belt! :D

Rocko
2008-12-07, 11:50
Be traditional dammit! It's a fan belt! :D

Traditional? Call em V-belts or drive belts!

ArgonPlasma2000
2008-12-08, 08:14
a broken timing chain can mess up your valves royally, to the point that the repair isn't worth it.

A broken belt will do it too.

One of our Saturns got salvaged with a busted timing belt. All 24 valves are bent, but the rest of the engine is clean as a whistle.

bornkiller
2008-12-08, 10:55
2.4 petrol yah? :confused:
You'll find the chain tensioner will wear before the chain does, however? chains do stretch but will last longer than a belt!
Theres my 2c worth.:rolleyes:

frinkmakesyouthink
2008-12-09, 11:05
Chains don't stretch, the links wear meaning that they go slack... but you knew that already :p

You can sometimes hear worn a timing chain tinkle if you listen carefully to the bottom of an engine, this means you should replace it.

Anyone know any good methods of knowing how worn a belt is? Because I don't know when mine was last changed... it looks pretty easy to get to so I might do it myself, and the timing needs setting anyway... I've never owned an OHC engine before :D

ArgonPlasma2000
2008-12-09, 11:18
Chains don't stretch, the links wear meaning that they go slack... but you knew that already :p

You can sometimes hear worn a timing chain tinkle if you listen carefully to the bottom of an engine, this means you should replace it.

Anyone know any good methods of knowing how worn a belt is? Because I don't know when mine was last changed... it looks pretty easy to get to so I might do it myself, and the timing needs setting anyway... I've never owned an OHC engine before :D

If you have an interference engine, replace it. It's better to spend 20 quid than have a dodgy belt snap. If it's not an interference engine, if the belt looks supple and black and doesn't have any cracks in the rubber or fraying in the cord, you should be good for a while. You should just replace it anyway. You can't fix it when your stuck on the side of the road.

A friend had his Metro serviced and the timing belt had almost no rubber left. It just had enough rubber to keep the cords hard. I love Suzuki engines. :)

bornkiller
2008-12-09, 12:14
Anyone know any good methods of knowing how worn a belt is? Because I don't know when mine was last changed... it looks pretty easy to get to so I might do it myself, and the timing needs setting anyway... I've never owned an OHC engine before :D
Argons right dude, it pays to change em.
(Coming from a person who's only changed his cam belt in his Corolla once since he owned it):(
They are pretty easy to do, they're quite accessible and you have enough mechanical aptitude to do the job.
(Timing marks are on the pulleys - all good)
I like push rod engines too. 5char! :D

frinkmakesyouthink
2008-12-09, 13:04
^ yeah I was going to change it anyway, I need a new strobe gun and there are literally no motor factors in this fucking tiny village that my parents live in, so I need to drive the car at least once more :D shouldn't be a problem really

Professor Skullsworth
2008-12-09, 22:54
^ dont confuse mechanical timing with ign timing. you dont need a timing light to set up your timing belt, either the marks line up or they dont. on the plus side, since it is a toyota, it may have marks on the belt itself saying exactly which tooth on the belt sits inside the marked timing cog's marked valley. it is a very simple and ingenious addition that all timing belts should have. anyhow good luck

frinkmakesyouthink
2008-12-09, 23:10
I'm not confusing them, I just need both :D the timing is out and I don't know when the belt was last changed

eesakiwi
2008-12-11, 08:52
k thanks guys.

what's weird though is that i looked under the hood, and there was something that resembled more of a timing belt, than a chain.

is there another part of the engine that would resemble this?

im not an expert, just took some basic classes in 'automotive mechanical'

Ahhhh, this is getting worse.

Timing chains can look like a double width chain, they can also look like a chain made only from interlocking metal stampings (with pins in there) they do/can look like a 'belt' of metal links.

However, theres probably no way you will see a timing belt, or timing chain, by just looking under the bonnet.

Timing chain. http://forums.nicoclub.com/zerothread?id=347473
Timing belt. http://www.tegger.com/hondafaq/sludge/timing_belt.jpg