After reading several threads regarding timing belts breaking and the kinds of bad things that can happen I was wondering why it is that timing CHAINS aren't used in all engines? I would think that the chain being stronger and more durable would be a better choice, especially with the "interference engines." What am I missing?
Originally posted by eaglevision4me I was always under the impression that timing chains are tougher to break. Thanks for the clarification.
its true that they are *tougher* to break... but I have owned 2 cars that the chains have broken or stripped the gears... granted both were above 100K miles... but then again.. most people are getting 100K on a belt anyway... and it is cheaper to replace.
the 2 cars were both GM... so it isn't some Dodge thing either. ANd I hate replaceing all the valves. they con't cost much, but it is just a pain in the ass.
a properly designed chain system will go 300k+ miles. Chains are more reliable and require less maintence, but if the system isnt designed properly or more imporatantly the car isnt taken care of in the first place it will fail.
the 2.7L is just a bad design.
GM's will go through some chains once in ahile...but the vast majority make it 200k+ in the V6s and V8s.
also the same seem to go with belts. The trep system is good and the belt lasts a long time.......the porsche 944 system is not so good requiring a 60K maintenance and even then there are plenty of failures
Chains are more suited to engines with an in the block single camshaft like an old school V8.
Double overhead cammed V engines require alot of chain to run everything. By the time you factor in tensioners, guides, lube and noise it starts to make the belt seem like a good idea.
Consider also the belt quaility has improved over the years.
In the LH 3.5's it's usually the water pump that tears everything up, not the belt.