SABB diesel Norsk traktor og motormuseum Stokke

Splash lubrication is a rudimentary form of lubrication found in early engines and transmissions. Such engines could be

external combustion engine An external combustion engine (EC engine) is a Reciprocating engine, reciprocating heat engine where a working fluid, contained internally, is heated by combustion in an external source, through the engine wall or a heat exchanger. The fluid t ...

s (such as

stationary steam engine Stationary steam engines are fixed steam engines used for pumping or driving mills and factories, and for power generation. They are distinct from locomotive engines used on railways, traction engines for heavy steam haulage on roads, steam car ...

s), or

internal combustion engine An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal comb ...

s (such as petrol, diesel or paraffin engines).

Description

An engine that uses splash lubrication requires neither oil pump nor oil filter. Splash lubrication is an antique system whereby scoops on the big-ends of the

connecting rod A connecting rod, also called a 'con rod', is the part of a reciprocating engine, piston engine which connects the piston to the crankshaft. Together with the crank (mechanism), crank, the connecting rod converts the reciprocating motion of the p ...

s dip into the oil sump and splash the lubricant upwards towards the cylinders, creating an

oil mist Oil mist refers to oil droplets suspended in the air in the size range 1~10 μm. Formation of oil mist Oil mist may form when high pressure fuel oil, lubricating oil, hydraulic oil, or other oil is sprayed through a narrow crack, or when l ...

which settles into droplets. The oil droplets then pass through drillings to the bearings and thereby lubricate the moving parts. Provided that the bearing is a

ball bearing A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this ...

or a

roller bearing In mechanical engineering, a rolling-element bearing, also known as a rolling bearing,ISO 15 is a bearing which carries a load by placing rolling elements (such as balls, cylinders, or cones) between two concentric, grooved rings called race ...

, splash lubrication would usually be sufficient; however,

plain bearing file:NYC 100-driving-axle-friction-bearing.jpg, Plain bearing on a 1906 S-Motor locomotive showing the axle, bearing, oil supply and oiling pad file:Linear-table with detail numbered.png, A sliding table with four cylindrical bearings file:GWR Spo ...

s typically need a pressure feed to maintain the oil film, loss of which leads to overheating and seizure. In a transmission, some of the gears are partially submerged in fluid, which transfers lubricant to the other gears, as long as the transmission is spinning. The splash lubrication system has simplicity, reliability, and cheapness within its virtues. However, splash lubrication can work only on very low-revving engines, as otherwise the

sump oil Cutting fluid is a type of coolant and lubricant designed specifically for metalworking processes, such as machining and stamping. There are various kinds of cutting fluids, which include oils, oil-water emulsions, pastes, gels, aerosols (mists ...

would become a frothy mousse. The Norwegian firm,

Sabb Motor Sabb Motor is a Norwegian maker of small marine diesel engines, mostly single-cylinder or twin-cylinder units. The firm was established as Damsgaard Motorfabrikk by two brothers, Alf and Håkon Søyland in 1925. The firm started building engines ...

, produced a number of small marine diesel engines, mostly

single-cylinder A single-cylinder engine, sometimes called a thumper, is a piston engine with one cylinder. This engine is often used for motorcycles, motor scooters, motorized bicycles, go-karts, all-terrain vehicles, radio-controlled vehicles, power tools an ...

or twin-cylinder units, that used splash lubrication.

Modern use of splash lubrication

Splash lubrication is still used in modern engines and mechanisms, such as: * the

Robinson R22 The Robinson R22 is a two-seat, two-bladed, single-engined, light utility helicopter manufactured by Robinson Helicopter Company. It was designed in 1973 by Frank D. Robinson, and has been in production since 1979. Development The majority of ...

helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...

uses splash lubrication on some

bevel gear Bevel gears are gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped. Bevel gears are most often mounted on shafts that are 90 degrees apart, but can be designed to work at ot ...

s. * all

BMW Bayerische Motoren Werke AG, trading as BMW Group (commonly abbreviated to BMW (), sometimes anglicised as Bavarian Motor Works), is a German multinational manufacturer of vehicles and motorcycles headquartered in Munich, Bavaria, Germany. Th ...

motorcycle A motorcycle (motorbike, bike; uni (if one-wheeled); trike (if three-wheeled); quad (if four-wheeled)) is a lightweight private 1-to-2 passenger personal motor vehicle Steering, steered by a Motorcycle handlebar, handlebar from a saddle-style ...

s with shaft drive use splash lubrication in the final drive hub. * British pre-unit and

unit construction : ''For the vehicle design where the vehicle's skin is used as a load-bearing element, see Monocoque.'' Unit construction is the design of larger motorcycles where the engine and gearbox components share a single casing. This sometimes includes ...

motorcycles, (such as Triumph, BSA and Norton) used splash lubrication in their gearboxes. * Cars and

lorries A truck or lorry is a motor vehicle designed to transport freight, carry specialized payloads, or perform other utilitarian work. Trucks vary greatly in size, power, and configuration, but the vast majority feature body-on-frame construction ...

invariably still use splash lubrication in their differentials.

References

External links

International Council for Machinery Lubrication

Machinery Lubrication magazine
(archived) Lubrication Tribology Lubricants {{automotive-tech-stub

Description

Modern use of splash lubrication

See also

References

External links