water in diesel fuel

[Rosey]

probably a stupid question but what would a small amount of water actually do to a diesel motor if it enters via the fuel supply? I can't imagine injectors or pump being overly happy, however would it really stuff them? I doubt you'd get compresson lock up from water in the fuel.

I heard somewhere that people somehow use to inject a small amount of water into diesels to improve fuel ecconomy over long distance, may be an old wives tale.

thoughts??

cheers

[Daisy]

I left my filler cap open when i was doin the 4.2 install and stupid me.. it rained..


So i primed all the fuel out (couldnt be bothered removin the fuel tank and it had no drainage plug on it) and refilled it and got one of those lucas filters with a water separator on them.

Pretty good investment i'd say.

Not sure on what damage it'd do but ill be readin this thread for the answers for sure.

TOM

[bogged]

I heard somewhere that people somehow use to inject a small amount of water into diesels to improve fuel ecconomy over long distance, may be an old wives tale.

Why do all diesels have water traps?
I would say Horseshit not wives tale!

Depending how much you mean by small amount in the first part of the question.

[Area54]

Ok, long post time.

The diesel fuel is used as both a lubricant and coolant to the injection pump in most diesel compression ignition motors. In the case of the lubrication side of the injecion pump, you have many metal components within the pump that run with very tight tolerances. The diesel runs through the pump acting as the main lubricant between these metal wear surfaces. Water is not a great lubricant in this instance, and of course accelerates the wear of components. The fuel filter's job is to trap the water and seperate it from the fuel as it travels through the filter medium. The problem with some of the diesel treatments out there is that they emulsify (act like a detergent) the water into the fuel so it can travel past the filter and enter the injection pump and then be burnt off during the combustion process. The pump then has a percentage of water replacing the lubricating properties of the fuel and premature wear in the pump occurs. Water present in the fuel will also rust components within the fuel injection system, from the injectors back.

The thing to remember with the fuel system in a diesel, is that the components all run within very close tolerances, any impurities that make it past the filter will reduce performance and possibly damage the pump.

Diesels do require a little more user maintenance, but worth it for long term reliability.

Clean air, clean fuel, clean oil, all components will wear at an even rate according to the engineers blueprints.

Buy a filter system that allow you to monitor the fuel condition (with a glass/plastic bowl type arrangment on the bottom of the fuel filter) drain the water/sediment off regularly, and change the filter every 5000km - a bit of overkill with the filter change, but at 8 bucks a throw for Delphi 296 filter cartridges it's cheap.

Replacing some of the rubber supply line to the filter and the pump with clear fuel rated lines will also allow you to diagnose any air suction problems/leaks.

[Area54]

I heard somewhere that people somehow use to inject a small amount of water into diesels to improve fuel ecconomy over long distance, may be an old wives tale.

Why do all diesels have water traps?
I would say Horseshit not wives tale!

Depending how much you mean by small amount in the first part of the question.

Might be talking about water injection via the intake manifold to lower air intake temps.

[Zeyphly]

i was told ages ago that diesel engines dont agree with water injection and it will cause the combustion chambers to become pitted and break away.