Commonrail engine

[Bangkok]

How does a commonrail diesel engine differ from the normal version?

[KebabMeister]

Unsure how you mean?

Some diesel ones drive the engine completely.  Others power an electric generator which they provides drive.

[Bangkok]

The Toyota Vigo and the Isuzu D Max / GM Colorado have Commonrail engines, apparently a new innovation

[thekraut]

I think it's got something to do with the injection system. If I remember correctly, common rail means that all the high pressure injection gear is connected, forming one hp-system, while in other diesel engines every cylinder has it's own, independent system.

[sddsddean]

Essentially thekraut is correct. On a normal diesel the fuel pump pumps diesel to each injector via its own pipe, but the pump is usually mechanically driven via the engine crank, so the pressure varies with the engine revs, which is ineffiecient. With common rail, there is a 'reservoir' which is maintained at high pressure by an electric pump (so no rev variation) and a 'computer' decides how much to open each injector and how much diesel to let in. This is all more efficient, but more complicated, so when it all goes tits up by the side of the road at 1.30 am, you have naff all chance of fixing it yourself. (Voice of experience?!)

[Garrards]

Common rail diesels perform far better than 'standard' diesels. My wife's 2.0 diesel Picasso outperforms my 2.0 Volvo!