Start/Stop is here to stay
#21
Lucas, the Prince of Darkness! I well remember the old Lucas electrics and the old joke about why the British drink warm beer..because the refrigerators were made by Lucas!
The only thing Lucas ever made well, in my opinion, were the Lucas Flamethrower driving lights. They were brilliant and among the first really good lighting for dark drives.
You raise some excellent points about the stop-start issue. I agree that unless there were a pressurized lubrication system that assured oil would be available to the cylinder walls during startup there could be a deleterious effect on longevity. The molecular structure of modern oils is so much different than the old oils that adhesion to cylinder walls and moving parts remains constant regardless of heat. However, as with all moving parts, a single revolution with no lubrication probably equates to months of normal wear. So if only once per day in your 17 start-stop cycles there was a lack of lubrication, I would guess you shave years off the effective life of an engine over the period of ownership.
Every new car seems to have this idiot system, as you noted, just to obtain a bit higher CAFE average. Thank goodness you do not drive an Evoque as I had a loaner this past week and it shuddered and shook with every restart.
The only thing Lucas ever made well, in my opinion, were the Lucas Flamethrower driving lights. They were brilliant and among the first really good lighting for dark drives.
You raise some excellent points about the stop-start issue. I agree that unless there were a pressurized lubrication system that assured oil would be available to the cylinder walls during startup there could be a deleterious effect on longevity. The molecular structure of modern oils is so much different than the old oils that adhesion to cylinder walls and moving parts remains constant regardless of heat. However, as with all moving parts, a single revolution with no lubrication probably equates to months of normal wear. So if only once per day in your 17 start-stop cycles there was a lack of lubrication, I would guess you shave years off the effective life of an engine over the period of ownership.
Every new car seems to have this idiot system, as you noted, just to obtain a bit higher CAFE average. Thank goodness you do not drive an Evoque as I had a loaner this past week and it shuddered and shook with every restart.
#22
They do think about this stuff. For example, read about the 'hydraulic impulse storage device' that's part of the ZF transmission. It retains pressure so that the transmission can shift quickly on restart without having to build up fluid pressure.
https://www.dropbox.com/s/b7666doqb4...trans.pdf?dl=0
https://www.dropbox.com/s/b7666doqb4...trans.pdf?dl=0
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Shearwig (10-30-2016)
#23
That is not the case when starting a cold engine, parts are cold, and not well-lubricated, which when start-up engine wear occurs. You can hate on start/stop until pigs fly, but added engine wear wouldn't be a valid reason to do so.
Last edited by Foosh; 10-30-2016 at 12:31 PM.
#24
A few years back I read an article about how starter systems needed to change for auto start/stop to be practical. The old gear-drive starter motors weren't designed for the usage these systems required, and the change was going to be alternators that also operated as electric motors, and that starting would be via the belts.
I didn't follow the development (not in the industry anymore) but the current system works well. It took some getting used to, but the only issue I have now is if I'm inept enough to stall the car (manual transmission). For all other times I just decide if it's appropriate. Stop and go on the freeway? Turn it off. Surface streets with long lights? Turn it on. I thought I'd never like it but quickly got to the don't care stage. It's like the headlights. One or off as needed.
I didn't follow the development (not in the industry anymore) but the current system works well. It took some getting used to, but the only issue I have now is if I'm inept enough to stall the car (manual transmission). For all other times I just decide if it's appropriate. Stop and go on the freeway? Turn it off. Surface streets with long lights? Turn it on. I thought I'd never like it but quickly got to the don't care stage. It's like the headlights. One or off as needed.
#26
This is only an issue if the engine is stopped long enough for the oil to settle back out of all of the oil passages. Note that Jag requires that an engine be stopped for at least 10 minutes before the oil level can be measured to ensure that a relatively accurate static oil level can be measured. Shutting an engine down for a couple minutes at a time will not compromise lubrication. Also note, the engine automatically restarts after just a couple minutes of sitting idle. The only additional wear is on the starter. If that has been designed for this type of service, that should also be a non-issue.
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Shearwig (10-30-2016)
#27
#29
When you're older
My issues with *** are several, I agree it's easy to hit the button-but I forget-then at the first stop it shudders to off. There has got to be a dramatic increase in starter wear and tear-even if system was upgraded to handle this it adds to cost and complexity. Finally, do your research, the fuel savings are minuscule. I know the factories are forced to explore all fuel savings but the cost, inconvenience (drive in bumper to bumper traffic with *** on for 5 minutes-extremely annoying) and minimal savings make this a poor feature.