I'm a shadetree mechanic with little knowledge of diesels. I noticed that diesel engines do not make what was a characteristic clattery sound so much in recent years. They are sometimes able to be mistaken for a gasoline engines. Anyone know why that is ?
Clatter of old diesels
- Thread starter Eddie7045
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Mainly new injection technology. Older engines would only inject fuel once during the power stroke. Newer engines are injecting up to 12 times per power stroke. That and tighter tolerances in just about every moving part in the engine. Ever heard the old wives tale that if your diesel wasn't leaking oil, something was wrong with it? Those days are long gone.
Not only have the engines changed, the fuel changed. Have an older diesel engine? Better be putting in an additive to simulate that older style of diesel fuel. New fuel has a much lower level of sulphur, and older engines needed that sulfur to lubricate them. Lower the fuel lubrication, and lower the engine life? Many diesel people say yes.
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In response to the concern that ultra low sulfur diesel (ULSD) fuel does not lost its lubricity due to its ~6 ppmw low sulfur content (vs. 500 ppmw diesel prior to ULSD), a lubricity agent is added to meet ASTM 975 diesel lubricity specification. It is added to diesel during terminal truck loading. This has been in effect since ULSD.
And not to mention, it was just this year that marine or "red" diesel was mandated to go to ULSD. Even then, LSD (500ppm) diesel in stockpiles can still be sold until 2014.
As Stephen said, there have been additives put into the new ULSD to help with lubricity. Ive been running ULSD in my 99 Dodge Cummins for almost 5 years now, and the VP44 injection pump on those engines are the most finicky pumps in the world, but they have no problems with the new fuel.
As Stephen said, there have been additives put into the new ULSD to help with lubricity. Ive been running ULSD in my 99 Dodge Cummins for almost 5 years now, and the VP44 injection pump on those engines are the most finicky pumps in the world, but they have no problems with the new fuel.
The first time I was in a diesel injection pump repair facility, and saw an injection pump in a test cell pumping the injectors into graduated beakers to measure stroke volume, I was amazed to hear what sounded like a diesel engine running with the characteristic CLACK CLACK CLACK sound. On engines with mechanical injection, most of the engine noise we think of as dieseling is not from the engine at all, but from the pump and injectors loading and unloading from cycling pressures reaching 2000 PSI.
Late model automotive diesel engines are now computerized electronically fuel injected, and most of the characteristic noise has been extinguished. However, in the process they have made the newer engines as electrically reliable as any equivalent gasoline engine.
Late model automotive diesel engines are now computerized electronically fuel injected, and most of the characteristic noise has been extinguished. However, in the process they have made the newer engines as electrically reliable as any equivalent gasoline engine.
Diesel shops that like to work, prefer the new fuel. Lol
Another difference in the old and new fuels, is the old fuel could sit forever and never grew mold in the fuel. The new fuel, if left to sit, can grow mold. The mold clogs up fuel lines and messes stuff up pretty bad. Some fuel additives restrict the growth of mold, as well as better lubricate your engine and remove water.
Another difference in the old and new fuels, is the old fuel could sit forever and never grew mold in the fuel. The new fuel, if left to sit, can grow mold. The mold clogs up fuel lines and messes stuff up pretty bad. Some fuel additives restrict the growth of mold, as well as better lubricate your engine and remove water.
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