Today’s diesel engines outperform the diesel engine technology of just a few years ago in many ways.
Original Equipment Manufacturers (OEM) now incorporate sophisticated, electronically controlled fuel injection systems that inject diesel fuel into engine cylinders as many as seven times per injection cycle at pressures up to 30,000 psi.
These new High Pressure Common Rail (HPCR) systems feature extremely tight tolerances between the fuel injector body and the injector plunger. Clearances can be as tiny as 1 -3 microns.
As early as 2008, OEMs began noticing injectors “sticking” in their HPCR systems. The affected engines seemed to operate fine at normal operating temperatures, but when shut down, they would be hard to start, run rough, or not start at all.
At the time, there was little understanding of the problem, or what was causing it. It was known that the problem wasn’t isolated to any one engine manufacturer or specific fuel or biodiesel blend. The operating problems continued to become more prevalent in the field and outside of the OEMs’ laboratories.
In 2009, after much analysis, it was determined that white-gray, soapy, waxy deposits were causing the sticky injectors. Further analysis revealed the new deposits, now termed “Internal Diesel Injector Deposits” (IDID) consisted of carboxylate salts.
Detergents that historically were effective at removing the carbonaceous deposits that form on injector tips and orifices exhibited only a limited effect on the new, waxy deposits. Even finer fuel filters were ineffective at preventing the problem.
So what was causing the new deposits? Researchers determined the carboxylate salt formation was related to the introduction of Ultra Low Sulfur Diesel (ULSD) fuel.
Corrosion inhibitor chemistry, traditionally used to maintain pipeline integrity, combined with insoluble sodium found in the ULSD fuel to produce the resulting carboxylate salts, which likely had been present in the fuel for years.
The deposits only manifested and became a problem as the new HPCR technology became widely used in diesel engines.
As a result, fuel additive manufacturers developed new, sophisticated detergent chemistry to address the problem. Recognizing the efficacy of the new chemistry, several OEMs now recommend fuels containing it or sell an additive product for conventional No. 2 diesel fuel.
Dieselex Gold from FS has been reformulated to incorporate improved detergency as well as several other performance upgrades to help your diesel engines run at optimum performance. For more information, see your local FS energy specialist.
Ken Reichert is GROWMARK’s refined and renewable fuels sales manager. His e-mail address is email@example.com