Marine Lubricants and Greases
Marine engines and onboard systems work through sustained loads, moisture and seasonal use. Rock Oil supplies engine oils, steering and gear fluids, greases, coolants and maintenance products for leisure craft, personal watercraft and commercial vessels, helping operators protect equipment across the boat.
Marine engine oils for your vessel and application
The marine range brings together dedicated two-stroke and four-stroke lubricants for different engine technologies and operating duties. Select by the engine manufacturer’s oil type, viscosity and performance requirements.
- MP3 ULTRA: advanced synthetic two-stroke oil for relevant direct-fuel-injection outboards, with NMMA TC-W3® certification.
- MP3 SPORT and BIO MARINE 3: semi-synthetic two-stroke and biodegradable ester-based options respectively, for suitable marine engine applications.
- MP PLUS SPORT: synthetic four-stroke oils in 10W-40 and 5W-30 for relevant outboard engines. MP PLUS SPORT 10W-40 carries NMMA FC-W Catalyst Compatible® certification.
- Inboard engine oils: MP4 SPORT synthetic 15W-40 and MP LITE-D multigrade diesel 15W-40 provide options for engines requiring their respective performance specifications.
- Personal watercraft: MPR INJECTOR provides advanced synthetic two-stroke lubrication for suitable injector and pre-mix applications, including specified Rotax-powered marine equipment.
Match the product to the engine and its lubrication system, following the stated servicing and mixing requirements.
MARINE-GUARD for commercial diesel duties
MARINE-GUARD 3015 TP and 4015 TP serve relevant medium- and high-speed trunk-piston diesel engines. These medium-alkalinity oils are supplied in SAE 30 and SAE 40 respectively, with TBN 15.
Rock Oil’s dedicated technical team can help you match the viscosity and alkalinity to the engine, fuel and operating requirements.
Supporting products for onboard systems
Steering, transmission and gear fluids
MARINE PSF serves specified power-steering and transmission applications, while MARINE HSF provides hydraulic steering lubrication. MP GEAR OIL is an SAE 80W-90 extreme-pressure gear oil with API GL-5 performance.
Bring steering, transmission and gear-unit servicing into the same onboard maintenance programme, with dedicated fluids for each system’s requirements.
Water-resistant marine greases
MPG UNIVERSAL MARINE GREASE, MG STERN TUBE GREASE and PRO-GUARD CA 2Z provide calcium-based options for relevant marine greasing duties. WATER RESISTANT 2 uses aluminium-complex technology, while HD ADHESIVE GREASE provides semi-synthetic, water-resistant lubrication.
Support bearings, stern tubes and other greasing points exposed to marine conditions. Grease technology and consistency depend on the component, load and lubrication system.
KOOL-GUARD coolants and antifreeze
The marine brochure includes propylene-glycol-based KOOL-GUARD MARINE MPG, alongside MEG -38, XL -38, VCS 50:50 PREMIX and PSi-OAT -38 for engines requiring their respective coolant technologies.
The wider KOOL-GUARD range provides concentrated and ready-to-use options for temperature control and cooling-system corrosion protection.
The specified coolant technology and dilution support temperature control and cooling-system corrosion protection through operation and seasonal use.
Corrosion protection and maintenance
SUPER MARINE INHIBITOR provides protective lubrication for suitable exposed and internal surfaces, helping resist rust formation. WHITE SPRAY GREASE and OPEN GEAR CHAIN & WIRE support further lubrication tasks.
SOC DEGREASER and COPPER ANTI-SEIZE provide options for relevant cleaning and assembly duties in marine workshops and onboard maintenance.
Support onboard maintenance and seasonal lay-up with products for cleaning, assembly, lubrication and corrosion protection.
Product guidance across your vessel or fleet
Browse our product catalogue filtered for marine products for specifications and available technical data sheets (TDS). Rock Oil’s dedicated technical team can provide up-to-date product information and help with engine requirements, fluid compatibility and servicing needs.
For advice on marine lubricants, biodegradable two-stroke options or supporting onboard products, speak to our technical team.
Keep your vessel ready for the next trip
Whether maintaining a leisure craft or managing a commercial fleet, bring together the products needed for engines, onboard systems and seasonal servicing with support from Rock Oil.
- Research the range
Browse our product catalogue filtered for marine products for specifications and available TDS. - Discuss your vessel and equipment
Get advice on engine oils, steering and gear fluids, greases and coolant requirements. - Plan servicing and storage
Speak to our dedicated technical team for current product information, compatibility guidance and corrosion-protection options.
Marine knowledge. British manufacture.
Rock Oil develops and manufactures its products in Britain, drawing on experience in two-stroke and four-stroke lubrication to support marine engines and onboard maintenance.
From outboards and personal watercraft to commercial diesel installations, our dedicated technical team can help you work through equipment specifications, operating conditions and product selection across the vessel.
Explore marine products
PRO-GUARD™ BENTONE-SYN HT 2M
PRO-GUARD BENTONE-SYN HT 2M is a heavy duty, high temperature bearing grease fortified with molybdenum disulphide. It has been designed for the effective lubrication and protection of ball, roller and…
PRO-GUARD™ Wire Rope LV
PRO-GUARD WIRE ROPE LV is specially formulated for ropes requiring a penetrating lubricant. PRO-GUARD WIRE ROPE LV’s penetrating action draws the lubricant to the core, coating the inner strands, protecting…
Stern Tube Grease
A premium quality, water resistant grease for use in industrial and marine applications where the presence of water and humid atmospheres can effect lubricating performance and be detrimental to the…