Constant stopping and starting hard on timing chains?

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Nov 29, 2009
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I've heard all these engines that constantly restart every time you come to a stop is hard on the timing chain. Is it because they start faster? How about the mail man or the ups driver that shuts his truck off every stop? Does that cause the same problem? Obviously, I'm talking about the gasoline vehicles, not the diesels because they don't have a timing chain.
 
That’s a new one. Not heard that before. Timing chain would be the least of my worries.
 
The coefficient of static friction is higher than dynamic. Theoretically the forces are higher to get moving again.

How that compares to the forces at 6000rpm tho...
 
Harder on everything that entails start/stop parts I'd imagine. How well they'll last will depend on the quality of parts. I've mentioned this before & remember one brand launched a 15-30 for start/stop vehicles. I didn't see it on the shelves for very long so it must have not sold well.
 
I've heard all these engines that constantly restart everytime you come to a stop is hard on the timing chain. Is it because they start faster? How about the mail man or the ups driver that shuts his truck off every stop? Does that cause the same problem? Obviously, I'm talking about the gasoline vehicles, not the diesels becaise they don't have a timing chain.

Yes, timing chains get more stress/tension during starts.
Its well known and fundamnetally a true statement.

Is it a signifcant issue for stop/start engines?
I dont think we know, or at least not yet. IMHO we really need years of stop/start being the standard to have the data to know if it affects reliability in a signifcant manner..... a lot would depend on how well made a particular timing chain is. Some manuafctuers make them more solid than others.
 
Seems logical. It puts a load on it more than if it were not having to stop and go. And a torque converter helps to smoothen things out as a manual could be harder on it but if an engine is designed well it shouldn't matter 99% of the time but with engines having to be made more efficient with smaller more efficient chains paired with thinner low hths oil it could be an issue in high mileage engines.
 
I hit my auto start stop OFF button as soon as I am ready to drive off.

Actually sometimes in rural area I leave it active and I drive around it.
I very slow roll thru signs and lights. No complete stops with foot on brake, and it doesn't activate

Timing chains + VVT and DOHC = garbage.

Gimmie back them smooth, silent, DRY toothed belts
 
I've heard all these engines that constantly restart every time you come to a stop is hard on the timing chain. Is it because they start faster? How about the mail man or the ups driver that shuts his truck off every stop? Does that cause the same problem? Obviously, I'm talking about the gasoline vehicles, not the diesels because they don't have a timing chain.
Why wouldn’t diesels have a timing chain?
 
That's the beauty of a diesel. They can run around the clock without shutting down except for basic oil and filter changes.

Gasoline engines can do the same, As a kid I remember going with my grandpa to fix irrigation pump engines.....A lot of them were gasoline. Ford, GM, & Chrysler big blocks, Hall-Scott, Continental ect.

I've seen Hall-Scott engines that dwarf a Cummins B-series
 
After scientism of the long-term advantages of stop/start talked with a mechanical engineer in the auto industry. He acknowledged that it does create different stress levels on specific parts of the engine/drive train but that the new vehicle featuring stop/start are modified in their design and development components to account for this. The end result is that reliability is NOT compromised. Seemed reassuring at the time, and NOT seen any data comparing stop/start and none stop/start to contradict this perspective, though no doubt time will tell but it's been a while now.
 
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