With the implementation of highly advanced common rail diesel injection systems, the requirements in terms of fuel purity are increasing. The fuel is injected at pressures of up to 2,500 bar, at which even tiny dirt particles act like projectiles and can cause damage to components or even system failure in the worst case scenario. With its MULTIGRADE F-MB 333 three-layer filter medium, the newly developed PU 11 001 z fuel filter from MANN-FILTER offers a pioneering solution for the protection of these modern injection systems.
This innovative filter, which features an encapsulated mixed fiberglass layer, achieves a filtration efficiency of more than 99.7 percent down to particles measuring four micrometers (in accordance with ISO 19438). For comparison: These particles are up to 18 times smaller than the width of a human hair. The PU 11 001 z thus stops 997 of 1,000 streaming particles.
The new filter comprises three layers: a fully synthetic fiber layer, referred to as the melt-blown layer, is responsible for increasing the dirt holding capacity. A cellulose/glass mixed layer with very fine glass fibers provides very high filtration efficiency. The final cellulose layer has a supporting function and additionally protects the injection system from escaping glass fibers.
Reliable operation even at low temperatures
The PU 11 001 z offers even more advantages: at excessively low temperatures, paraffin crystals can form in the fuel and clump together. These clumps can then block the fine pores of the fuel filter. An electric heater integrated in the filter housing of the PU 11 001 z, melts the flocculated paraffin chains again, preventing premature clogging of the filter when the filterability temperature limit is reached.
The three-stage water separation of the PU 11 001 z additionally ensures that finely distributed water droplets are reliably separated from the diesel fuel. At the end of its service life, the new fuel filter still achieves a separation performance of over 90 percent of tiny 10-micrometer water droplets.
Fuel-saving and clean servicing
The filter housing can be easily accessed and opened from the underside of the vehicle. When changing the filter, a patent-pending bayonet bracket in the housing cover and on the filter ensures that the filter remains in the housing and does not fall out. The fuel can flow into the cover, where it collects and drains away via the drain screw. “Consequently, the fuel doesn’t flow unchecked out of the screw-on cover, allowing the mechanic to change the filter cleanly,” explains Lena Ketschau, Product Manager Fuel Filters Automotive Aftermarket at MANN+HUMMEL. “Moreover, the filter being changed can be removed easily using a supplied handle that serves as a removal tool”. This handle engages into the element from underneath. Turning the filter releases it at the bayonet catch and it can be pulled out of the housing.
The new PU 11 001 z with its three-layer filter medium thus meets all the current and future requirements relating to filter fineness for gasoline and diesel engine applications. With it, MANN-FILTER is adding to its broad portfolio of fuel filters a solution that offers even better performance and meets the prescribed standards.
MULTIGRADE F-MB 333 is already mass produced for different premium car models. From fall 2016, the product will be available in the independent automotive aftermarket as MANN-FILTER PU 11 001 z Kit for C-, E- and S- Class Mercedes-Benz.
