Does idle stop end oil lubrication, Damage engine?

[blackman777]

Honda's first VCM engine (2004-07) worked just fine. How could they screw-up the redesign?

(ponder)

FTC stopped Slick 50 from making these claims: "Every time you cold start your car without Slick 50 protection, metal grinds against metal in your engine." ----- "With each turn of the ignition you do unseen damage, because at cold start-up most of the oil is down in the pan. But Slick 50's unique chemistry bonds to engine parts. It reduces wear up to 50% for 50,000 miles."

In fact, the FTC said, "most automobile engines are adequately protected from wear at start-up when they use motor oil as recommended in the owner's manual. Moreover, it is uncommon for engines to experience premature failure caused by wear, whether they have been treated with Slick 50 or not."

 

[Shannow]

OK, so the FTC DIDN't say that most wear doesn't occur at start-up, despite your assertion that they did...

They told Slick 50 to stop making their claims regarding oil draining off, and protection offered by teflon on the parts...BIG Difference...

http://papers.sae.org/600190/
http://papers.sae.org/952474/

 

[Shannow]

Paper by Federal Mogul

http://www.federalmogul.com/en-US/Media/Documents/CrankshaftbearingsMTZ122010.pdf

Quote:
Start-stop systems, which can be found in more and more vehicles today, pose a particular challenge. They increase fuel
efficiency by 5 % and more through switching off the engine during standstill as often as possible. To avoid any impact on drivability, the engine is cranked very quickly as soon as the driver engages the clutch.

For the crankshaft bearing half shells and the big end bearings this can translate into frequent high-speed rotary movement
before a hydrodynamic film is established. During this phase of boundary lubrication metal-to-metal contact can occur between
the crankshaft surface and the bearing’s sliding surface. This was not an issue while the number of engine re-starts totaled at what was generally understood to be a normal magnitude. However, in a vehicle with start-stop system this effect can necessitate new technological solutions to avoid premature bearing wear, depending on the driving cycle. Consequently future engines for start-stop applications need to be
designed for 250,000 to 300,000 starts. Traditional bearing shells with aluminum or copper lining show severe wear after
only 100,000 cycles.


Interestingly with SG Iron cranks (probably more of an issue with tighter clearances)

Quote:
Using crankshafts made from grey cast with fine spherical nodules of graphite (Nodular Cast Iron, NCI) poses special requirements to plain bearings.

A characteristic of NCI’s morphological structure are hard ferrite envelopes around the graphite nodules. Despite even the most careful surface machining via polishing these circular structures covered by caps will not fully disappear. Those caps may break off during running condition and damage the bearing surface.

If the bearing has no suitable mechanism to compensate this effect, cast iron crankshafts can quickly cause bearing seizure. With the Irox overlay, a combination of the embedded hard particles’ polishing effect and the polymer’s ductility prevent this type of problem from occurring

 

[demarpaint]

^^ That would be the first thing I disable upon bringing a new vehicle equipped with that technology home.

I'd just make sure it can be done before I bought the car. Opinions vary.

 

[fdcg27]

Straight from a bearing manufacturer, so probably meaningful.
100,000 cycles would be more than 200K miles even for a car that never goes farther than the nearest grocery.
Start and stop the engine five times on that short trip and it's pretty obvious that problems might ensue.
The obvious solution doesn't involve the engine.
A hybrid capable of pure EV operation in stop and go driving would avoid this problem entirely.
Something like a Volt.
Yeah, they're costly, but it looks like an owner really will save enough fuel that the marginal cost over a typical similar car is recovered sometime before 100K.

 

[bigt61]

Originally Posted By: fdcg27
Straight from a bearing manufacturer, so probably meaningful.
100,000 cycles would be more than 200K miles even for a car that never goes farther than the nearest grocery.
Start and stop the engine five times on that short trip and it's pretty obvious that problems might ensue.
The obvious solution doesn't involve the engine.
A hybrid capable of pure EV operation in stop and go driving would avoid this problem entirely.
Something like a Volt.
Yeah, they're costly, but it looks like an owner really will save enough fuel that the marginal cost over a typical similar car is recovered sometime before 100K.

Batteries are a "fuel", how long do they last before you have to "refuel"? Or do you just stick the next sucker with that problem? Not trying to be cynical, but there are still a few long term cost with a lot of these EVs that need to be worked out. Like solar panels and their "free electricity". It takes you 10 years to break even on the cost of installation (after govt subsidies) and then, after 10 years, your original panels are worn out and need replacing. Repeat cycle.

 

[MolaKule]

A simple solution, if you are paranoid about start-up lubrication, would be a small secondary oil pump which would provide some measure of oil pressure during those restarts.

 

[fdcg27]

Battery life in the Volt is an unknown, just as it is with the Nissan Leaf and the Tesla as well as a host of hybrid vehicles.
We do know that battery life for the Prius is typically not an issue and that battery pack replacements are typically not required over the life of the car.
The packs can be rebuilt, as well, by locating and replacing the bad cells.
The battery packs used in various cars may turn out to be of no concern, although indie shops, emergency responders, recovery drivers and scrap yards will all need to learn to deal with them safely.

 

[Shannow]

Originally Posted By: MolaKule
A simple solution, if you are paranoid about start-up lubrication, would be a small secondary oil pump which would provide some measure of oil pressure during those restarts.


True, back in Uni, there was an SAE paper (on microfiche no less) of fitting pre-oilers to engines...summary was 4-5 times reduction in wear...still boundary for a little, as oil pressure provides neither separation, or lubrication, but the oil supply is there before stuff moves.

With OEMs heading down the path of electric variable displacement pumps, it's a simple programming step to kick the oil flow on before the engine turns...still boundary 'though.

 

[Errtt]

I don't like it.
I don't want my engine to stop, stopping my AC when its hot out.
I do want my engine to stop via manual stop feature (me spinning the key back to turn it off) when I'm ready to.
Would rather keep all fluids moving as much as possible anyway.

 

[CapitalTruck]

Originally Posted By: Zaedock
Originally Posted By: demarpaint
We'll know soon enough cars equipped with it are out and about, and people are disabling the technology so its not loved that's for sure.



We will indeed. Personally, I don't like extra "features" and the start/stop is just another gimmick to save fuel. The same folks who will buy the car will end up blowing past you on the highway anyway (probably with underinflated tires!).



I love going 70 in a 55 and having Priuses blow by me at 80. "There goes money well spent..." is what crosses my mind.

 

[CapitalTruck]

A couple of things to point out to some of the posters. The AC shouldn't stop as they have electric compressors on these vehicles (I think). Also, they don't use traditional starters. Rather, they use an Alternator/starter unit for the start stops that turn the engine and begin to propel the vehicle while starting. Think gasoline powered golf carts. They work the exact same way.

 

[FetchFar]

Originally Posted By: MolaKule
A simple solution, if you are paranoid about start-up lubrication, would be a small secondary oil pump which would provide some measure of oil pressure during those restarts.


Or an oil accumulator (stores some pressure like a capacitor holds voltage) would hold some pressure for a minute or two, depending on its size. Probably a better solution than an additional pump (expense), since an accumulator is just a small tank with check valves.

 

[CELICA_XX]

This is a non-issue.

How does no one mention the PRIUS ????

They have been doing the start / stop for 17 years.



Originally Posted By: CapitalTruck
I love going 70 in a 55 and having Priuses blow by me at 80. "There goes money well spent..." is what crosses my mind.

Even at 80, they are still getting better MPG's than most every car on the road.

 

[SilverC6]

BMW states that there could be additional wear from this feature.

The fact that auto manufacturers have implemented this technology doesn't mean that it will not damage your vehicle.

It's all about fuel economy.

 

[CELICA_XX]

Originally Posted By: SilverC6
The fact that auto manufacturers have implemented this technology doesn't mean that it will not damage your vehicle.

I'm just saying its a time-tested proven technology.

Oil lubrication engine failure is nonexistent.

 

[Alfa_Hadera]

Originally Posted By: CELICA_XX

Oil lubrication engine failure is nonexistent.


Wait a minute. What? You said... What?

With one sentence you have just undermined the entire pyramid of logic that is the foundation of my BITOG experience. This is mean and I demand you expand and elaborate.

 

[BobThe]

Originally Posted By: SilverC6
BMW states that there could be additional wear from this feature.

The fact that auto manufacturers have implemented this technology doesn't mean that it will not damage your vehicle.

It's all about fuel economy.

And with BMW using high boost turbo 4's in the 3 series (and I think the 5 series as well), do they have an oil pump that keeps oil moving to the turbo when it turns the engine off at a stop light?

 

[OneEyeJack]

The Prius in taxi service where the drivers beat the cars and drive well over 100K a year have no lubrication problems. Their cycles of start and stop are much more frequent than any daily driver would ever experience. They also have few mechanical problems because there is no shifting of gears in the transmission and no reverse gear (you back up on one of the 2 electric motors) and no fan belt on the engine to worry about. Also they are experiencing zero battery problems much to the disappointment of critics of hybrid cars. Upon viewing the inside of a Prius engine with over 500K miles there was no abnormal wear. We were able to look inside the engine because the car was destroyed in an accident. By the way, the battery was not damaged although the car was a total wreck. The running gear was put back together and made into an emergency generator set. It was easy and worked so well that people are looking in junk yards everywhere for a wrecked Prius.

 

[Clevy]

Originally Posted By: OneEyeJack
The Prius in taxi service where the drivers beat the cars and drive well over 100K a year have no lubrication problems. Their cycles of start and stop are much more frequent than any daily driver would ever experience. They also have few mechanical problems because there is no shifting of gears in the transmission and no reverse gear (you back up on one of the 2 electric motors) and no fan belt on the engine to worry about. Also they are experiencing zero battery problems much to the disappointment of critics of hybrid cars. Upon viewing the inside of a Prius engine with over 500K miles there was no abnormal wear. We were able to look inside the engine because the car was destroyed in an accident. By the way, the battery was not damaged although the car was a total wreck. The running gear was put back together and made into an emergency generator set. It was easy and worked so well that people are looking in junk yards everywhere for a wrecked Prius.



I gotta assume that a wrecked Prius is going to cost far more than an actual generator