Does idle stop end oil lubrication, Damage engine?

[OneEyeJack]

Originally Posted By: 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



$280

 

[Shannow]

Given that a primary operating mode of the Prius is engine off, and rapid start, are you sure that there's not design features (like the Federal Mogul paper I linked), or micropolishing, to reduce boundary lube effects that help the engine have no problems ?

Or did they just slap another engine in the hybrid chassis and say "OK have at it !" ?

 

[OneEyeJack]

There is an insulated thermos that feed hot water back into the system. In an engine like this the most wear if from just after start to completely warm not the time in just turning over the engine. Toyota did a lot of work to keep the engine warm once started and to warm it up quickly if needed.

 

[Shannow]

Originally Posted By: raytseng
The Honda designers made the feature, it's going to work fine without damage.
It's not some jury-rigged backyard thing you're using.


Have today downloaded a Honda Paper 27-1e_13, which deals with wear material production, and a comparison between stop start and steady state.

Shows about double the generation of debris in stop-start versus steady state.

Not enough to make a pile of failed engines at the side of teh road, but wear is there.

 

[Jetronic]

Originally Posted By: CATERHAM

But the Stop/Start feature doesn't kick-in until the engine is up to normal operating temp's and the engine's oil system is of course fully primed. Under such conditions I don't see how engine wear can be increased.


Well that is false. If conditions are good (weather related) start/stop systems can kick in a minute after starting...

 

[Jetronic]

Originally Posted By: 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.


this isn't true either. Upgraded starters, yes... and the S/S won't kick in for a host of reasons, one is that the set temperature in the car is far from the outside temp. no electric AC compressors either.

Full hybrid cars get electric compressors.

 

[friendly_jacek]

Originally Posted By: Shannow
Originally Posted By: raytseng
The Honda designers made the feature, it's going to work fine without damage.
It's not some jury-rigged backyard thing you're using.


Have today downloaded a Honda Paper 27-1e_13, which deals with wear material production, and a comparison between stop start and steady state.

Shows about double the generation of debris in stop-start versus steady state.

Not enough to make a pile of failed engines at the side of teh road, but wear is there.


for some reasons that are not clear to me honda is behind on the hybrid technology compared to toyota.

toyota ICE is spined by more powerful motor than typical starter (faster) and fuel/ignition is turned only after reaching desired RPM.

the net effect is no wear penalty.

Quote:

Cadillac engine at lower mileage [200k] was cleaner.
But wear on Prius was only slightly worse than for the Cadillac (surprisingly low
wear for 400K miles)

http://www.api.org/~/media/files/certification/engine-oil-diesel/forms/whats-new/9-dap-understanding-lubricant-requirements-of-hybrid-electric-vehicles-dclarke-infineum-usa.pdf

 

[Amirkhat]

I've been skeptical of idle stops, the only way I would buy a car that did this is if it had an integrated electric oil pump that started prior to the engine resuming. I'm not saying engines that don't have this are dry starting, but I think its

 

[Amirkhat]

I've been skeptical of idle stops, the only way I would buy a car that did this is if it had an integrated electric oil pump that started prior to the engine resuming. I'm not saying engines that don't have this are dry starting, but I would just feel better about it..its just too new to know exactly how a lack of the aforementioned pump would impact the engine after years of stop and go traffic (post warranty).