Internal Diesel Injector Deposits – We’re on guard!
Mark Dehner is GROWMARK marketing manager of refined and renewable fuels.
Posted on: 10/20/2011 2:49:00 PM
Today’s diesel industry is very different from the past. New government regulations are pushing engine Original Equipment Manufacturers (OEMs) to meet extremely stringent emissions standards, while also reducing fuel consumption. These same regulations force fuel refiners and distributors to process and additize fuel more than ever before. These changes have created a perfect storm in the field, collectively affecting off-road, on-road, marine, and railroad diesel equipment owners, known in the industry as internal diesel injector deposits (IDID).
In order to meet the new regulations, engine manufacturers have implemented many new technologies, including exhaust gas recirculation, selective catalyst reduction, diesel particulate filters, variable geometry turbochargers, and high pressure common rail injection systems. High pressure common rail (HPCR) includes a single fuel rail that is pressurized to injection pressures of up to 30,000 psi. The injectors in this system are electronically actuated, meaning the fuel injection timing and duration is independently controlled by each injector. In order to improve fuel atomization and injection precision, injectors for the HPCR system are manufactured with tighter tolerances than traditional injectors.
Diesel fuel properties changed with the introduction of Ultra Low Sulfur Diesel fuel (ULSD) affecting diesel engines and fuel systems. One significant change was polarity; the new ULSD is less polar than low sulfur diesel and high sulfur diesel. This caused certain particulates to no longer be soluble, causing fuel system issues. One of these particulates, called sodium carboxylic acid salt, would travel downstream and accumulate in fuel injectors.
Since the new HPCR injectors had such tight tolerances, the carboxylate salts would deposit on the internal parts (IDID), causing the injectors to stick open or closed. The result of this sticky injector phenomenon was rough running engines, increased exhaust smoke, loss of power, loss of fuel economy, and increased emissions.
In 2011, more and more cases of injector failure in the field related to internal injector sticking are being recorded. GROWMARK and FS member cooperatives are committed to providing a solution to this performance issue for our customers. We will be re-formulating our premium diesel fuel to include state-of –the-art detergency. This new detergent will not only prevent sodium carboxylic acid salts from collecting inside the injectors, it will also clean up existing deposits. Once the internal injector deposits are eliminated, users can see restored power and fuel economy, as well as reduced emissions.