A diesel engine can go as long as a million miles, or 20,000 hours, between overhauls.  But these workhorse engines can be brought to their knees by a faulty fuel delivery system, which is why operators throughout central and northern Wisconsin rely on K & S Fuel Injection.

The core business of this Weston facility is rebuilding fuel injection pumps and injectors and turbochargers for diesel engines of all sizes, but especially in mid-range applications such as pick-ups, delivery vehicles, farm equipment and logging.

Unlike gasoline engines which use spark plugs to ignite the fuel/air mixture, diesel requires tremendous pressure in the cylinders to fire.  A fuel injector pump builds the pressure to fire the injector, which has tiny orifices that supply an atomized fuel mixture to the cylinder.

"The compression on a diesel is about 400-450 points per cylinder, compared to 150 in a gas engine,” said Jason Maki, who acquired the family-owned business. “The fuel injection system plays a critical role for the engine to run right.”  Like anything mechanical, these devices can wear out or become contaminated, but these heavy-duty parts often last as long as the engines they feed.

Technology is constantly changing in this industry, said Maki, showing the newest type of injector nozzle.  Looking something like a narrow-barreled pistol, this device shoots fuel into a cylinder three times for every compression stroke of the engine, compared to just once for older style nozzles.  They fire at 25,000 pounds per square inch under full load, compared to 2,000-4,000 psi for older models, making the engines more powerful, fuel efficient and quiet.

K & S maintains complete testing equipment for all brands of injectors, and a dynamometer to measure power output under different loads.  A sideline of the business is a diesel performance products division, started in 1994, that can take a pickup truck from “mild to wild”, according to Maki.  As much as 100 horsepower can be added simply by changing a programming box.

Diesels have gained a foothold in the consumer truck market and select autos primarily to their fuel mileage.  Maki’s personal VW Passat diesel averages 45 MPG, and full-size ¾ ton pickups typically average 20 MPG.

The company’s solid customer base includes County Materials, for both equipment and trucks; Nortrax Equipment, suppliers of John Deere equipment ranging from garden tractors to huge mining machines; Spee-dee Delivery Systems and FedEx.  K & S is an authorized dealer for Cummins mid-range diesels and provide service work for all diesel fuel systems and turbocharger.  Most diesels now have a turbocharger, a device that uses exhaust gas to spin a turbine wheel which pulls more air into the engine to provide a cleaner burn and more power.

K & S is one of only six shops in Wisconsin specializing in diesel fuel injection and turbochargers.  They provide on-site service in the field and draw customers from an area bordered by Plainfield to the south, all of northern Wisconsin and Michigan’s Upper Peninsula to the far north, Thorp to the west and Wittenberg to the east.