AEROSHELL PISTON ENGINE OILS AEROSHELL PISTON ENGINE OILS For many years the performance of aircraft piston engines was such that they could be lubricated satisfactorily by means of straight mineral oils, blended from specially selected petroleum base stocks. However, demand for oils with higher degrees of thermal and oxidation stability necessitated ‘fortifying’ them with the addition of small quantities of non-petroleum materials. The first additives incorporated in straight mineral piston engine oils were based on the metallic salts of barium and calcium. In highly-rated engines the performance of these oils with respect to oxidation and thermal stability was excellent, but the combustion chambers of the majority of engines could not tolerate the presence of the ash deposits derived from these metal-containing additives. Following extensive operational success in a wide range of civil engines, military specifications based on the general characteristics of AeroShell W Oils were prepared and issued. AeroShell W Oils were in service with the world’s airlines and aircraft operators for many years when they operated big transport piston-engined aircraft, during which time these oils became virtually the standard for all aircraft piston engines. Nevertheless, supplies of straight AeroShell Oils remained available primarily for running-in the aircraft piston engine and for the few operators who required them. Today these oils (both AeroShell W Oils and AeroShell Oils) are still required for the smaller piston-engined aircraft flying in air taxi operations, flying clubs or flown by private pilots. In the early 1980s a semi-synthetic multigrade W oil for piston engines (AeroShell Oil W 15W-50) was added to the range. This grade has become very popular amongst engine manufacturers and operators alike. In order to cater for those Lycoming engines which need improved load-carrying (i.e. those engine models which require the addition of Lycoming Additive LW 16702) AeroShell Oil W 15W-50 was upgraded in 1986 to include an antiwear additive. PISTON ENGINE OILS To overcome the disadvantages of harmful combustion chamber deposits, a non-metallic, i.e. non-ash forming, polymeric additive was developed which was incorporated in blends of selected mineral oil base stocks, to give the range of AeroShell W Oils.

AEROSHELL PISTON ENGINE OILS In recent years utilisation of piston engine aircraft has decreased, resulting in the aircraft spending more time on the ground. This led to an increase in corrosion being seen inside the engine. In order to combat this, AeroShell Oil W 15W-50 was further upgraded in 1993 to include a very effective anti-corrosion additive package. 3.2 To cater for the demands of operators of light sport aviation piston engines, two new grades – AeroShell Oil Sport Plus 2 (for 2-stroke engines) and AeroShell Oil Sport Plus 4 (for 4-stroke engines) have recently been introduced. With...

AEROSHELL PISTON ENGINE OILS PISTON ENGINE OILS Due to differences in metallurgy, operating conditions and fuel specifications, an aircraft oil will not meet all of the automobile/heavy-duty engine's requirements. In addition, the aviation oils are not qualified for this application and their use could result in voiding the warranty and/or reduction in engine life. Thus automobile oils MUST NOT be used in aircraft engines which use or specify SAE J-1899 or J-1966 oils. Similarly aviation oils MUST NOT be used in automobile engines. SELECTION OF RIGHT GRADE OF OIL For the majority of aircraft...

AEROSHELL PISTON ENGINE OILS RADIAL ENGINES Many operators are interested in extending oil change intervals. As a general rule extensions are not recommended for the following reasons: Radial engines utilise special parts and, depending upon the type of aircraft, application and climate are often subject to specific problems not seen in other types of piston engines. - many engine manufacturers do not approve extended intervals - possibility of losing engine manufacturers’ warranty on the engine - possibility that extended intervals will shorten engine life In a radial engine each bank of cylinders...

AEROSHELL PISTON ENGINE OILS It is important to note that the information gained is only as good as the sampling procedure. A single test is not enough to reveal trends and significant changes, it can only tell an operator if there is already a serious problem. Operators should therefore:■ T ake samples properly For best results, take the sample about midway through the draining of hot oil from the sump. A sample pulled off the bottom may be dirtier than normal. The sample should be taken the same way every time. An improperly taken sample can lead to mistaken conclusions about engine problems....

AEROSHELL PISTON ENGINE OILS PISTON ENGINE OILS AeroShell straight mineral oils are blended from selected high viscosity index base stocks. These oils do not contain additives except for a small quantity of pourpoint depressant (which is added when improved fluidity at very low temperature is required) and an antioxidant. APPLICATIONS AeroShell Oils are available in four different viscosity grades: AeroShell Oil 65 - AeroShell Oil 80 - AeroShell Oil 100 - AeroShell Oil 120 The suffix for each grade corresponds to the viscosity of the oil at 210°F in Saybolt Universal Seconds. The appropriate...

AEROSHELL PISTON ENGINE OILS PISTON ENGINE OILS AeroShell W Oils were the first non-ash dispersant oils to be used in aircraft piston engines. They combine non-metallic additives with selected high viscosity index base stocks to give exceptional stability, dispersancy and anti-foaming performance. These additives leave no metallic ash residues that can lead to deposit formation in combustion chambers and on spark plugs, which can cause pre-ignition and possible engine failure. APPLICATIONS AeroShell W Oils are available in four different viscosity grades: AeroShell Oil W80 - AeroShell Oil W100...

PISTON ENGINE OILS EQUIPMENT MANUFACTURERS APPROVALS AeroShell W Oils are approved for use by the following engine manufacturers:- Typical Properties A viscosity/temperature chart is shown at the end of this section. NOTES AEROSHELL PISTON ENGINE OILS PISTON ENGINE OILS