The relationship between the extended service life of Fuel pumps and additives needs to be verified through tribological parameters: Laboratory bench tests show that the cleaning additive containing 0.15% polyetheramine (PEA) can reduce the wear rate of the impeller shaft sleeve by 42% (from the reference value of 0.8μm/ thousand kilometers to 0.46μm/ thousand kilometers). According to the data of the SAE paper in 2023, with the continuous use of fuel additives that comply with the API SP standard, the thickness of the lubricating film of the fuel pump motor bearing increased from 0.25μm to 0.38μm, and the probability of micro-pitting corrosion on the contact surface decreased by 65% (from 3.2 times /mm² to 1.1 times /mm²). Five-year tracking data from a certain German automaker shows that the average lifespan of Fuel pumps in vehicles with regular addition of cleaning agents reached 150,000 kilometers, an increase of 23% compared with the non-use group (122,000 kilometers in the control group).
The influence of fuel additives on system resistance has a threshold effect: when the concentration of the cleaner exceeds 0.3%, the pressure drop of the fuel filter screen decreases from the standard value of 12kPa to 8kPa, and the flow recovery rate increases by 18%. However, tests by the Southwestern Research Institute in the United States found that when the concentration of additives containing metal-based catalysts (such as manganese-based MMT) reaches 30ppm, a hard deposit layer of 8-12μm will form on the surface of the Fuel Pump impeller, causing the dynamic balance deviation to increase from 0.5g·mm to 2.3g·mm. The vibration amplitude exceeds the allowable value of the ISO 10816-3 standard (4.5mm/s vs 2.8mm/s limit). In the large-scale recall of a certain American car brand in 2019, 23% of the fuel pump failures were related to the excessive eccentricity of the impeller mass caused by illegal additives.
The economic analysis of antioxidants shows that adding 0.1% benzotriazole derivatives can reduce the wear rate of Fuel Pump brushes from 3mg/ thousand hours to 1.2mg/ thousand hours and extend the brush life from 80,000 kilometers to 120,000 kilometers. Based on the average annual mileage of 13,000 kilometers in the United States, using compliant additives can save 180 yuan in replacement costs each year (the average price of the original fuel pump is 240 yuan, and the labor cost is 120 yuan). However, the North American Lubricant Association warns that “fuel-efficient” additives containing siloxane can increase the fuel conductivity from less than 5pS/m to 50pS/m, causing the brush arc frequency to surge from 200 times/minute to 1500 times/minute, and accelerating the formation of commutator grooves (with a pumping efficiency 15% lower when the depth is greater than 0.2mm).
The material compatibility study reveals that the mixed Fuel containing >15% biodiesel needs to be matched with specific additives: The ASTM D975 standard requires that the acid value of B20 biodiesel must be <0.5mg KOH/g; otherwise, the swelling rate of the Fuel Pump seal will exceed 3% (the original factory design tolerance is 1.5%). A 2022 Brazilian market survey shows that when using B30 fuel without added acid corrosion inhibitors, the lifespan of nitrile rubber sealing rings has been shortened from the designed value of 100,000 kilometers to 47,000 kilometers, and the leakage probability has increased to 8.3 times per thousand units per year (the benchmark value of 0.7 times). The measured data of a certain European truck fleet shows that after adding 0.2% metal passivator, the corrosion rate of the fuel pump plunger pair decreased from 0.05mm/ year to 0.01mm/ year, and the growth rate of fit clearance decreased by 80%.
Compliance usage strategy suggestions: Screen additives in accordance with the ISO 12103-1 standard to ensure that the particulate matter cleaning efficiency is ≥85% (in the particle size range of 5-10μm), while controlling the fuel ash content ≤0.01% (by mass ratio). The joint statement of the three major North American automakers pointed out that additives that comply with ILSAC GF-6A certification can increase the fatigue life of key components of Fuel pumps by 30-40%, but warned against the mixed use of additives with different formulations (precipitation may occur when the pH value difference is greater than 1.5). Insurance data shows that the annual maintenance claim rate of car owners who use additives in a standardized manner has decreased by 28%, but excessive use (> 150% of the manufacturer’s recommended amount) instead increases the probability of fuel pump failure by 17%.