Variable displacement oil pump in Cruz

[Jeepster_nut]

I was reading an article on MSN and it mentioned that the Cruz uses a variable displacement oil pump to only pump the necessary oil to maximize fuel savings. This sounds interesting to me, but it also makes me cringe should something have a hiccup

http://editorial.autos.msn.com/blogs/autosblogpost.aspx?post=d1bd997f-ec45-4177-8aac-9b18ffd530de

"Or consider the Chevrolet Cruze. The Eco version of the compact is rated at 42 mpg on the highway. But even the standard version includes a variable-displacement oil pump that pumps only what's needed as a way to improve engine efficiency".

 

[Hokiefyd]

This is fairly recent technology, but its use is spreading. As I recall, Chrysler's Pentastar 3.6L V-6 uses it, and I know Toyota's AR-series engines (2.5L/2.7L I-4) use it also.

 

[Nick R]

More info
http://green.autoblog.com/2010/08/26/var...uze-hit-40-mpg/

Interesting.

 

[CBR.worm]

Some of the BMW's have it. I am not sure if ours does or not.

It is kind of worrying. My brother's BMW has an electric water pump and variable displacement oil pump. both things that I used to think of as generally simple and reliable.

We (me) accept that european cars require more 'maintenance' after some number of years than other cars, partially due to the additional technology. With the trend towards complicating everyhing from the steering systems to cooling/lubrication systems to capacitive touch interfaces for air conditioning/audio, I can't help but wonder if they are all going to become higher maintenance as they age.

Today an inexpensive american car with all this technology is great. What will it be like to own this car in 10 years? Will all this stuff still work?

 

[Jeepster_nut]

Thats an interesting link thanks for it.
It is electrical and mechanical- wow I just dont know what to think. Esp. the way electrical stuff seems to have gremlins from time to time. I assume they engineered in some sort of fail safe though in case of the unthinkable. Perhaps it goes into full open mode, pumping 100% of oil needed should a hiccup occur...

 

[CBR.worm]

I hope that if any of the control systems fail the spring will push it to high flow/pressure.

 

[A_Harman]

Mercedes also uses a variable displacement oil pump.
And there is also the trend toward electric power steering instead of the existing hydraulic systems. Imagine how fun it would be if the motor fails...
These kinds of systems will become more common as CAFE standards increase.

 

[Shannow]

I'd not be worried about control units failing, as the device shown in the link looks to be purely mechanical in nature.

It looks like a "constant" pressure, variable volume hydraulic pump.

Oil pressure acts on the right side of the tab at 12:00, forcing the housing to the left, and reducing displacement...pressure rises, volume drops, pressure drops, volume rises.

It's tried and trusted in industry, with 10s of thousands of hours of operation common, but not oft seen in cars

 

[ms21043]

The article says it's electronically controlled? Why would they need to do that? Looks like they borrowed that pump out of an old 200R4 trans.

 

[morris]

i like high tech as much as any one . BUT is it REALLY needed?

 

[Shannow]

It's not high tech, the design has been around forever...I've never used one industrially, as they are pretty pricey in the hydraulic world.

I can't see how that pump COULD be electronically controlled, as the supply port to the actuator vane can be seen tapped directly from the oil discharge port.

 

[punisher]

700R4s have been using that design variable displacement pump for decades.

 

[steve20]

anyone think the pivot will be the first thing to wear out on the engine?--unless it's diamond hard