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Seamus
23-09-2006, 09:04 AM
It seems that 'common rail' is the new catch phrase with a lot of the new diesels coming out. Anybody able to explain in laymans terms what it is and what benefits are gained?

Regards
Seamus

Lucky_Phill
23-09-2006, 09:41 AM
Someone will do a better job than me in regard to this.

I am under the impression that it is a very effecient fuel delivery system.

Basically having the fuel delivered under pressure from a tube close to the injectors.

OK< Kev, are you there and can you enlighten us all ??

Phill

ShaneJ
23-09-2006, 10:01 AM
Thisd may help:

http://en.wikipedia.org/wiki/Common_rail

Pitsta
23-09-2006, 11:25 AM
Mate I recently test drove a hilux with common rail & what it do'es is reduce the lag in the turbo , much more like a petrol vertion than ever
& more KW to boot .Exelleration is preety crisp & aconomy the same....

mark ;)

Lucky_Phill
23-09-2006, 04:53 PM
Thanks for the link Shane. It appears I was just about right ::) ::)

Phill

Lucky_Phill
23-09-2006, 04:57 PM
Common rail direct fuel injection is a modern variant of direct injection system for Diesel engines. It features a high-pressure (1000+ bar) fuel rail feeding individual solenoid valves, as opposed to low-pressure fuel pump feeding pump nozzles or high-pressure fuel line to mechanical valves controlled by cams on the camshaft. Third generation common rail diesels now feature piezo injectors for even greater accuracy, with fuel pressures up to 1700 bar.

this is from the abovementioned link.

Phill

Big_Kev
24-09-2006, 07:20 PM
Laymens terms/ Typical old style deisel engine had a fuel pump with individual elements (ie;6 elements for 6cylinder) pumping fuel at 5000psi in a burst to the injector and would spray the fuel into the combustion chamber in one hit. The injector would open and deliver the fuel when the set pressure of the injector was reached.The amount of fuel supplied is dependent on the rack position/setting.

Common rail has one large pump delivering the fuel to a manifold mounted on the side of the engine block (ie; the commomn rail) at 15-25000 psi. from this rail the solenoids or unit injectors are connected.
The fuel is delivered to the solenoids where fuel injection is controlled electronicaly at ground zero/ right at the injection point.
This electronic method allows for much greater control of the fuel delivery in as little as a mammo second.
Also the fuel can now be introduced in short bursts with many bursts during the one combustion, allowing infinite control of the combustion process (ie; less fuel is now required to give the same performance)
This along with advances in turbo charger tech is creating much better performance, economy, efficiency and emmissions unsurpassed by petrol engines.

Typicaly the big name Japanese 4X4 manufacturers will wait for others to bring out the latest and greatest and then copy the tech to save some bucks for the big marketing campain making out the did all the hard work.

Hope this helps.

In the begining man created the jeep 4x4, Everything else is merely an imitation.

Seamus
24-09-2006, 07:52 PM
All, thanks for the replys - much appreciated.

Seamus

MyEscape
05-10-2006, 05:45 AM
Reel Hard,

That's probably the best explanation I've heard, in simple terms, so far.

Keep up the good work. Interesting your thoughts on the japanese models, still following the leaders.

Steve

Kopey
15-10-2006, 09:26 AM
In the begining man created the jeep 4x4, Everything else is merely an imitation.


Jeep a Chrysler group is now owned by Mercedes (A German company anyway) too, correct me if I'm wrong, hence the advancement in technology CRD Grand Cherokee (Australian versions made in Austria) . The Japs were always noted for copying, do a good job of it too I might add, as so do the rest of the world eg: expansion chamber exhaust on 2 strokes, compression ignition - diesel engine, supercharger, etc all German inventions. The Germans had direct injection in their Messerschimdt BF 109 fighter planes back in 1936!!

Just some thoughts anyway
Cheers Ads ;)

Big_Kev
16-10-2006, 08:59 AM
Daimlier/Chrysler

Nitrous Injection

Kopey
22-10-2006, 03:06 PM
As Shelby said,"You can't make a silk purse out of a sour's ear, but you can make a damn Fast Pig." ;D ;) ;)

Chrysler Dodge Viper - 8 litre V10 ;D ;D ;)
510 horses, 535 ft/lbs torque, 0 - 60MPH in 3.9 secs, how do you like them apples Ferrari! ;D ;D

Just love it ;)

Gotta excuse me sometimes,(got nothing to do with common rail) love things mechanical. ;)