4 ms·

You are right that chains are superior to belts, but MB is hardly the only manufacturer using timing chains. Chains are actually becoming more popular, not less

by ptmcc 4y ago

You are right that chains are superior to belts, but MB is hardly the only manufacturer using timing chains. Chains are actually becoming more popular, not less popular, especially as interference engines have also become more common. My 2021 Mazda uses a timing chain. My 2004 BMW uses a timing chain. My old 1990 BMW had a chain. My folks' 2019 Lexus and 2016 Toyota both use chains. Honda was a notorious holdout that still mostly used belts for a long time, but even they are coming around and some new models use chains now.

jacquesm 4y ago
Interesting! So there is a kind of resurgence in this. Nice to see that other manufacturers take the longevity and service of their engines serious for personal transportation. There was a point in time where MB seemed to be the lone holdout and the only other manufacturers that used chains were mostly making trucks (and Porsche). To me it's a no brainer, especially with an engine where the pistons don't clear the valves when they are active. The kind of engine damage that a broken timing belt results in is usually enough to completely scrap the engine. I wonder if those other manufacturers chains are also rated for the life of the engine or rather not.
- ptmcc 4y ago
  > I wonder if those other manufacturers chains are also rated for the life of the engine or rather not. Mostly yes they are, which is wonderful compared to timing belts. It rubs my engineer brain intensely wrong to have such a critical engine component be designed as a wear item, especially when its failure can cause engine rebuild levels of damage. However not all manufacturers' quality lives up to the intended design. VW/Audi have a spotty record with various well-known timing chain problems ranging from bad chain tensioners that fail and cause the chain to jump timing to plastic chain guides that break and wreak general havoc. But for most cars a timing chain will last the life of the engine.
classichasclass 4y ago
My '08 Civic Si had a timing chain, one of the few models that did at the time. Used to startle the service techs who weren't expecting it.
bsagdiyev 4y ago
Yep, the N54 out of my 335i had timing chains. Replacing that during the engine build wasn't fun, but it was still solid at 130k.

by ptmcc 4y ago

jacquesm 4y ago

Interesting! So there is a kind of resurgence in this. Nice to see that other manufacturers take the longevity and service of their engines serious for personal transportation. There was a point in time where MB seemed to be the lone holdout and the only other manufacturers that used chains were mostly making trucks (and Porsche). To me it's a no brainer, especially with an engine where the pistons don't clear the valves when they are active. The kind of engine damage that a broken timing belt results in is usually enough to completely scrap the engine. I wonder if those other manufacturers chains are also rated for the life of the engine or rather not.

ptmcc 4y ago
> I wonder if those other manufacturers chains are also rated for the life of the engine or rather not. Mostly yes they are, which is wonderful compared to timing belts. It rubs my engineer brain intensely wrong to have such a critical engine component be designed as a wear item, especially when its failure can cause engine rebuild levels of damage. However not all manufacturers' quality lives up to the intended design. VW/Audi have a spotty record with various well-known timing chain problems ranging from bad chain tensioners that fail and cause the chain to jump timing to plastic chain guides that break and wreak general havoc. But for most cars a timing chain will last the life of the engine.

classichasclass 4y ago

My '08 Civic Si had a timing chain, one of the few models that did at the time. Used to startle the service techs who weren't expecting it.

bsagdiyev 4y ago

Yep, the N54 out of my 335i had timing chains. Replacing that during the engine build wasn't fun, but it was still solid at 130k.