El Mar®GEO

Non-Detergent, Ashless Natural Gas Engine Oil

Phillips 66®El Mar GEO Oil is a high-quality, non-detergent, ashless gas engine oil designed primarily for use in Ajax 2-stroke cycle natural gas engines. The SAE 15W-40 viscosity grade meets the low-temperature viscosity requirements of Ajax engines where cold starts and frequent start/stop cycles may be encountered.

Features & Benefits

• Ashless formulation helps minimize port deposits

• Protects against sludge and varnish formation

• Excellent resistance to oxidation and nitration

• Protects against scuffing and wear

• Protects against rust and corrosion

• Excellent water-separating properties

• Low carbon-forming tendency

• Compatible with emissions system catalysts

• Does not contain any bright stock, which can cause harmful carbon deposits


• Ajax 2-stroke cycle natural gas engines (SAE 15W-40

• Older, horizontal-type 2-stroke cycle natural gas engines, such as those manufactured by Cooper-Bessemer and Worthington (SAE 30/40)

Technical Details

Licenses & Approvals

El Mar GEO Oil is approved for use under the following OEM specification:

• DuPont Specification A4V4

Additional Details
SAE Grade15W-40
Specific Gravity @ 60°F0.869
Density, lbs/gal @ 60°F7.24
Color, ASTM D15002
Flash Point (COC), °C (°F)240 (464)
Pour Point, °C (°F)-40 (-40)
Viscosity, Kinematic
cSt @ 40°C107
cSt @ 100°C14.2
Viscosity Index135
Cold Cranking Viscosity, cP @(°C)6,400(-20)
Acid Number, ASTM D974, mg KOH/g0.04
Carbon Residue, ASTM D524, wt %0.1
Sulfated Ash, ASTM D874, wt %<0.01
Phosphorus, wt %0.011