Harder on engine, idling or restart?
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Restart is hard on starter, idle is hard on oil(fuel dilution).
I shut down the engine if I need to wait more than 3-5 minutes.
I shut down the engine if I need to wait more than 3-5 minutes.
I'm not convinced that starting is hard on anything except the starter. It was in the carbureted days when shutting down hot and then restarting could lead to pre-ignition "kicking back" against the starter, or making a couple of very loud detonations just as the engine starts... but those days are gone.
If its less than 10 minutes and your maintenance is up to date let it run,especially in the cold and wiyh synthetic oil. When I lived with my dad in Wyoming we left the truck running going to check on oil rigs and during travels to N.Dakota we locked it,left in running and lifted the rear end barely off the ground to keep wheels spinning at like 3mph so the teeth in rear end wouldnt break in the 90's. Miss that time with my dad.
If you live in Texas it depends upon what's harder on YOU. Do I internally debate this topic in August if I'm stuck at a train or long light? Hmm. It's 100 degrees and I'm going to turn off the A/C because I'm concerned about fuel dilution...
Idling is supposed to be so hard on vehicles but ever notice police cars and taxi cabs run forever and never get shut off? I know I idle my company truck minimum of 4 hours to 8 hours a day and never had a issue. Every one went over 200,000 and didn't use any oil or any other issue.
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Coming out of NYC got stuck in traffic today in my Rav4. Literally took 1.5 hours to go 1 mile. Kept the car running just like everyone else caught with me. It was 90°, hot and humid. Plus had to keep creeping. If this happened on a routine basis, I'd think about increasing my OCI from 5000 miles to maybe 4000 or 3000 miles. But since it's just a one time deal I'm not going to worry about it and I'll stick to my 5000 miles OCI.
Idling is against the law in NJ in parking lots so I'd shut it down and restart.
Maybe you could give more details to the scenario you're thinking of?
Idling is against the law in NJ in parking lots so I'd shut it down and restart.
Maybe you could give more details to the scenario you're thinking of?
Syn oil 5000 OCI...fuggetaboutit
Idle long time against law in NJ ? Sounds like England as a congestion tax or something lol. Glad the East Coast doesnt run the heartland of america.
Great replies, thanks.
I've always heard that starts are hard on an engine. Not excessively so but you're running pistons through cylinders and cranks in bearings etc. with just a remnant of oil until the pressure kick in and keeps up. Obviously motors are designed for this but the more it happens the greater chance for that microscopic wear that turns into shorter engine life.
At the same time I've heard that idling is hard on an engine because you're running the lowest possible rpms/oil pressure and at the same time running a constant wear pattern instead of varying speeds and load.
Neither?
How do you plan to manage that? Never drive in a city? Never run errands or make short trips? Very interested to hear this plan
I've always heard that starts are hard on an engine. Not excessively so but you're running pistons through cylinders and cranks in bearings etc. with just a remnant of oil until the pressure kick in and keeps up. Obviously motors are designed for this but the more it happens the greater chance for that microscopic wear that turns into shorter engine life.
At the same time I've heard that idling is hard on an engine because you're running the lowest possible rpms/oil pressure and at the same time running a constant wear pattern instead of varying speeds and load.
Neither?
How do you plan to manage that? Never drive in a city? Never run errands or make short trips? Very interested to hear this plan
Originally Posted By: 440Magnum
I'm not convinced that starting is hard on anything except the starter. It was in the carbureted days when shutting down hot and then restarting could lead to pre-ignition "kicking back" against the starter, or making a couple of very loud detonations just as the engine starts... but those days are gone.
Lots of extra wear on the starter (not a big deal) and ring gear (kind of a big deal).
However, if they idled I'm sure they would just dump a lot of fuel in. Modern vehicles can idle super lean. And start up pretty easily.
I don't think either on a modern vehicle is as destructive as it was on something that's old and carbureted.
I'm not convinced that starting is hard on anything except the starter. It was in the carbureted days when shutting down hot and then restarting could lead to pre-ignition "kicking back" against the starter, or making a couple of very loud detonations just as the engine starts... but those days are gone.
Lots of extra wear on the starter (not a big deal) and ring gear (kind of a big deal).
However, if they idled I'm sure they would just dump a lot of fuel in. Modern vehicles can idle super lean. And start up pretty easily.
I don't think either on a modern vehicle is as destructive as it was on something that's old and carbureted.
Going to side with the neither camp. There are cars that already shut off at red lights after a few seconds that start up instantly. If the wear was bad they wouldn't do it to save such little gas if it added a decent bit of wear (over the life of the vehicle).
Only time start up really does any "damage" is after long periods of rest since the lubercants have had time to settle.
Only time start up really does any "damage" is after long periods of rest since the lubercants have had time to settle.
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And even after your car has been off long enough to cool the oil to ambient and drain most of the excess oil to the sump, the wear on that "dry" startup is probably only 10% of the total wear that occurs during oil warm up to beginning of Normal Op Temperature (175-180 deg). If your car was turned off from fully hot for less than say 5-10 minutes. You're probably generating almost miniscule wear on a hot restart.
Neither is hard on your engine. What is hard is the warmup cycle on your engine from cold to normal op temperature, especially in very cold winters.
Neither is hard on your engine. What is hard is the warmup cycle on your engine from cold to normal op temperature, especially in very cold winters.
I drove an 01 Toyota Tundra V8 I used for in-town newspaper deliveries to street corner boxes and inside buildings. If I had to cross a street or enter a large building I turn the engine off. For nearby and quick drops I left the engine running. The thought I kept in the back of my head was to minimize starter wear since the starter is located in the valley of the engine.
I had to replace the starter a couple years after I left that job anyways.
I think the most part that was hard on the engine was me mashing the gas pedal from every stop.
I had to replace the starter a couple years after I left that job anyways.
I think the most part that was hard on the engine was me mashing the gas pedal from every stop.
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Start-stop is harder on the engine (bearings) than idling would ever be.
Every time you stop the engine, especially hen hot, the flywheel end main bearing sits down hard on the bottom shell of the last main, and the accessory belt end is lifted pretty hard against the top shell of the front bearing.
When you crank it to restart, these two interfaces are metal/metal (well tribofilm/tribofilm) until the oil wedge is established.
Like MANY of these fuel saving strategies, they aren't being done to make your engine last longer.
And if I'm wrong....then why are engine bearings these days being designed with "stop start" requirements in mind ?
Never heard of a bearing design being specifically for idling.
Every time you stop the engine, especially hen hot, the flywheel end main bearing sits down hard on the bottom shell of the last main, and the accessory belt end is lifted pretty hard against the top shell of the front bearing.
When you crank it to restart, these two interfaces are metal/metal (well tribofilm/tribofilm) until the oil wedge is established.
Like MANY of these fuel saving strategies, they aren't being done to make your engine last longer.
And if I'm wrong....then why are engine bearings these days being designed with "stop start" requirements in mind ?
Never heard of a bearing design being specifically for idling.
every new car kills the engine when you stop at light. some make it easy to defeat that, others not so easy.
does anybody know when this "feature" started getting in the car? once we have a decade of experience and 300K miles with them, we will know if it works or not.
does anybody know when this "feature" started getting in the car? once we have a decade of experience and 300K miles with them, we will know if it works or not.
Originally Posted By: Shannow
Start-stop is harder on the engine (bearings) than idling would ever be.
Every time you stop the engine, especially hen hot, the flywheel end main bearing sits down hard on the bottom shell of the last main, and the accessory belt end is lifted pretty hard against the top shell of the front bearing.
When you crank it to restart, these two interfaces are metal/metal (well tribofilm/tribofilm) until the oil wedge is established.
Like MANY of these fuel saving strategies, they aren't being done to make your engine last longer.
And if I'm wrong....then why are engine bearings these days being designed with "stop start" requirements in mind ?
Never heard of a bearing design being specifically for idling.
It is for that reason that I would disable start stop as soon as I took title to a new car with that feature. Fortunately it can still be done AFAIK.
Start-stop is harder on the engine (bearings) than idling would ever be.
Every time you stop the engine, especially hen hot, the flywheel end main bearing sits down hard on the bottom shell of the last main, and the accessory belt end is lifted pretty hard against the top shell of the front bearing.
When you crank it to restart, these two interfaces are metal/metal (well tribofilm/tribofilm) until the oil wedge is established.
Like MANY of these fuel saving strategies, they aren't being done to make your engine last longer.
And if I'm wrong....then why are engine bearings these days being designed with "stop start" requirements in mind ?
Never heard of a bearing design being specifically for idling.
It is for that reason that I would disable start stop as soon as I took title to a new car with that feature. Fortunately it can still be done AFAIK.
I bought an '16 F150 with the 2.7 EcoBoost, which has the start/stop feature. I happen to love it, and if I didn't there is a handy button on the dash to disable it.
From what I've read about the 2.7 is it doesn't even use the starter during stop/start. It leaves a piston neat TDC, then when starting is called for it generizes the alternator to roll the engine over. It happens so seamlessly its hardly noticeable. If stuck in congested traffic and it shuts off there are several factors that will call for a re-start, with one being the need for heat/cooling.
I don't know how much it saves, but it is nifty.
From what I've read about the 2.7 is it doesn't even use the starter during stop/start. It leaves a piston neat TDC, then when starting is called for it generizes the alternator to roll the engine over. It happens so seamlessly its hardly noticeable. If stuck in congested traffic and it shuts off there are several factors that will call for a re-start, with one being the need for heat/cooling.
I don't know how much it saves, but it is nifty.
Originally Posted By: Vikas
every new car kills the engine when you stop at light. some make it easy to defeat that, others not so easy.
does anybody know when this "feature" started getting in the car? once we have a decade of experience and 300K miles with them, we will know if it works or not.
Well, not every. It seems more common in Europe. It was on the diesel MB I rented in Germany last year. Eventually, I turned it off as I had enough to think about driving in a foreign country but it seems like a good idea and the system worked very well.
every new car kills the engine when you stop at light. some make it easy to defeat that, others not so easy.
does anybody know when this "feature" started getting in the car? once we have a decade of experience and 300K miles with them, we will know if it works or not.
Well, not every. It seems more common in Europe. It was on the diesel MB I rented in Germany last year. Eventually, I turned it off as I had enough to think about driving in a foreign country but it seems like a good idea and the system worked very well.
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