An oil treatment system for an internal combustion engine in one implementation includes an elongated dipstick tube defining a tube axis and a first flow passageway, a housing arranged on the dipstick tube and defining an internal cavity, an oil treatment apparatus disposed in the internal cavity, and a retainer coupled to the housing. The retainer may have a cylindrical body comprising an elongated first flow protuberance insertably received through the oil treatment apparatus to establish fluid communication between the oil treatment apparatus and the first flow passageway of the dipstick tube. The retainer comprises a cavity through which oil may be added directly to the first flow passageway of the dipstick which may be fluidly coupled to an oil sump of the engine. The oil treatment apparatus may be an oil filter. An oil treatment additive may optionally be added to the housing.

An oil level measuring device has a distal end and a proximal end. The oil level measuring device includes an arm comprising a first channel and a second channel, an electronic oil level sensor comprising a measuring mean configured to measure the level of the oil in an oil pan and a connecting port, the measuring mean being hosted into the first channel of the arm, a dipstick hosted into the second channel of the arm and configured to dip into the oil in the oil pan.

An oil level measuring device has a distal end and a proximal end. The oil level measuring device includes an arm comprising a first channel and a second channel, an electronic oil level sensor comprising a measuring mean configured to measure the level of the oil in an oil pan and a connecting port, the measuring mean being hosted into the first channel of the arm, a dipstick hosted into the second channel of the arm and configured to dip into the oil in the oil pan.

An oil treatment system for an internal combustion engine in one implementation includes an elongated dipstick tube defining a tube axis and a first flow passageway, a housing arranged on the dipstick tube and defining an internal cavity, an oil treatment apparatus disposed in the internal cavity, and a retainer coupled to the housing. The retainer may have a cylindrical body comprising an elongated first flow protuberance insertably received through the oil treatment apparatus to establish fluid communication between the oil treatment apparatus and the first flow passageway of the dipstick tube. The retainer comprises a cavity through which oil may be added directly to the first flow passageway of the dipstick which may be fluidly coupled to an oil sump of the engine. The oil treatment apparatus may be an oil filter. An oil treatment additive may optionally be added to the housing.

An oil treatment system for an internal combustion engine in one implementation includes an elongated dipstick tube defining a tube axis and a first flow passageway, a housing arranged on the dipstick tube and defining an internal cavity, an oil treatment apparatus disposed in the internal cavity, and a retainer coupled to the housing. The retainer may have a cylindrical body comprising an elongated first flow protuberance insertably received through the oil treatment apparatus to establish fluid communication between the oil treatment apparatus and the first flow passageway of the dipstick tube. The retainer comprises a cavity through which oil may be added directly to the first flow passageway of the dipstick which may be fluidly coupled to an oil sump of the engine. The oil treatment apparatus may be an oil filter. An oil treatment additive may optionally be added to the housing.

A system, as an engine with a crankcase containing oil or a fluid mixed with oil, has a reservoir containing liquid that extends up to a level of the fluid. A dipstick support structure supports a dipstick on it so that the dipstick extends into the fluid past the level of the fluid, and so that the dipstick is manually removable from the dipstick support structure by a user. An electrical system is connected with the dipstick, and the electrical system electrically senses the level of the fluid based on an electrical characteristic of the dipstick that varies with the varying level of the fluid when the dipstick extends into it. The electrical characteristic may be capacitance of the dipstick detected by sequential charging and discharging of the dipstick to produce a square wave electrical signal the frequency of which corresponds to the level of fluid.

A system, as an engine with a crankcase containing oil or a fluid mixed with oil, has a reservoir containing liquid that extends up to a level of the fluid. A dipstick support structure supports a dipstick on it so that the dipstick extends into the fluid past the level of the fluid, and so that the dipstick is manually removable from the dipstick support structure by a user. An electrical system is connected with the dipstick, and the electrical system electrically senses the level of the fluid based on an electrical characteristic of the dipstick that varies with the varying level of the fluid when the dipstick extends into it. The electrical characteristic may be capacitance of the dipstick detected by sequential charging and discharging of the dipstick to produce a square wave electrical signal the frequency of which corresponds to the level of fluid.

Methods and systems for sensing a fluid level associated with an engine are described. The method comprises generating an input signal and applying the input signal to a resistive portion and a capacitive portion of a fluid level sensing device, measuring a first varying output of the resistive portion of the fluid level sensing device through a first channel of a controller of the engine, measuring a second varying output of the capacitive portion of the fluid level sensing device through a second channel of the controller of the engine, and translating at least one of the first varying output and the second varying output into a level of fluid and outputting the level of fluid.

Methods and systems for sensing a fluid level associated with an engine are described. The method comprises generating an input signal and applying the input signal to a resistive portion and a capacitive portion of a fluid level sensing device, measuring a first varying output of the resistive portion of the fluid level sensing device through a first channel of a controller of the engine, measuring a second varying output of the capacitive portion of the fluid level sensing device through a second channel of the controller of the engine, and translating at least one of the first varying output and the second varying output into a level of fluid and outputting the level of fluid.

An outboard motor with improved maintainability and attachable to a hull of a marine vessel includes an internal combustion engine and a cowl to cover the internal combustion engine. The internal combustion engine includes an oil filler to feed oil thereto and an oil filter to filter the oil. In a case that a direction perpendicular or substantially perpendicular to a bottom of the hull is a vertical direction, the cowl is separable into a top cowl to cover an upper portion of the internal combustion engine and a side cowl to cover a side portion of the internal combustion engine. At least a portion of the oil filler or at least a portion of the oil filter is located above a separating line which is a boundary between the top cowl and the side cowl.