[rmwtsou]

Am I correct in assuming that the Prius engine will last longer than that of a conventional car because it is being assisted by the motor and that it is turned off so often?

Also, does anyone know the durability of electric motors in comparison with internal combustion engines? What lubricates the internal moving parts of a motor?

Thanks for any answers!


Bob, 2004 #8 Super White

 

[Daniel]

I believe a more important factor is that the ICE in the Prius is always running at its design rpm. The power-split device allows for a total disconnect between engine speed and wheel speed, thus avoiding the extreme wear-and-tear of low engine speed at very low vehicle speed.

I think it is really cool that the ICE can run one MG to produce electricity, which in turn powers the other MG to move the car, thus allowing the ICE to turn fast while the car is moving slow. You benefit from the greater efficiency of the ICE at its design rpm, and you benefit from reduced wear and tear at design rpm.

It's reasonable to expect long engine life under sich conditions.

On the other hand, you can generally expect very long life from any Toyota (or Honda) engine.

I don't know about the electric motors, but I am under the impression that they are generally more durable than gasoline engines.

 

[Ray Moore]

It is not a safe assumption that the engine in the Prius would last longer than the engine in a non-hybrid Toyota due to run time because Toyota presumably took this into consideration in the design phase. Lighter components usually lead to greater efficiency and shorter life, so there is a compromise and a balance to be reached in the design of any engine system. I would assume that Toyota would have been faced with these same design decisions. I would assume a very long life for this engine because Toyota has made the most reliable products for decades now. That being said, you will need to take proper care of the engine in order to benefit from their efforts. I did replace an engine in my Toyota truck after neglecting my coolant for too long.

 

[nsfbr]

Regarding electric motors of the type used in the Prius, their lifetime far exceeds any ICE. The life limiting mechanisms are: bearings, insulation breakdown, and magnet corrosion/bondline failure.

Assuming Toyota knows what they are doing, none of those items would happen in the life of the car except for extremely rare manufacturing defects. I would guess on the order of 100,000 hours for a properly designed motor.

 

[Joel]

Look at the factory warranty on the drive train - this tells a lot.