Engine oil inboard

Oil for gasoline & diesel inboard engines - Marine engine oil

Marine engine oil for gasoline and diesel inboard engines ensures stable lubrication, thermal stability and reliable wear protection in maritime operation. Specially formulated oils protect against corrosion, deposits and loss of performance. Selection is based on engine type, manufacturer specification, viscosity class and operating conditions.

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LIQUI MOLY 15W-40 Mehrbereich New Generation 4-Takt Marine Motoröl API SL, 1 Liter
LIQUI MOLY
LIQUI MOLY 15W-40 Mehrbereich New Generation 4-Takt Marine Motoröl API SL, 1 Liter
article nr.25089

All-season oil for gasoline and diesel boat engines, e.g. for Mercruiser, Yanmar, Volvo Penta. Miscible with all commercially available engine oils. Volvo Penta ref. no. 22479638

28,31 EUR
baseprice: 28,31 EUR / l
incl. 19% VAT
Lieferung Wed 19. Aug - Mon 24. Aug 2026 **
24 months statutory warranty
To the oil guide
Ravenol Marine Motor Oil Inboard Diesel SHPD 10W-40, 1 liter
Ravenol Marine Motor Oil Inboard Diesel SHPD 10W-40, 1 liter
article nr.03909

All-season low-friction oil for marine diesel engines with oil specification API CI-4, ACEA E7, ACEA B4, API CF
For Volvo Penta, Mercruiser, Yanmar, OMC, MTU, Iveco, Ventus Deutz, Perkins and Caterpillar, among others.

13,28 EUR
baseprice: 13,28 EUR / l
incl. 19% VAT
Lieferung Wed 19. Aug - Mon 24. Aug 2026 **
24 months statutory warranty
Displaying 21 to 22 (of 22 products)
  • Over 15 years’ experience in the marine spare parts trade
    Over 15 years’ experience in the marine spare parts trade
  • Official Mercury & MerCruiser dealer
    Official Mercury & MerCruiser dealer
  • A wide range of boat engine spare parts from A to Z
    A wide range of boat engine spare parts from A to Z
  • Spare parts for Volvo Penta, MerCruiser, Yamaha, Honda, Suzuki and more
    Spare parts for Volvo Penta, MerCruiser, Yamaha, Honda, Suzuki and more
  • Fast delivery for maintenance, servicing and repairs
    Fast delivery for maintenance, servicing and repairs
  • Order boat spare parts conveniently online 24/7
    Order boat spare parts conveniently online 24/7

Importance of engine oil in the inboard engine

Engine oil performs key tasks in the inboard engine: It reduces friction, cools stressed components, protects against corrosion and binds residues from the combustion process. Especially in a maritime environment with high humidity and changing load conditions, stable lubrication is crucial for the service life of the engine.


Differences between gasoline and diesel engine oil

Gasoline and diesel inboard engines have different requirements:

  • Gasoline engines: Focus on clean combustion, deposit reduction and thermal stability at high speeds.

  • Diesel engines: Higher pressure load, greater soot formation and higher compression forces - require special additive packages with increased cleaning and pressure stability.

The choice of the right engine oil must be precisely matched to the engine type.


Requirements for marine engine oils

Marine engine oils must:

  • offer high thermal stability

  • ensure effective corrosion protection against salt water

  • build up a stable lubricating film during load changes

  • Minimize oxidation and oil ageing

  • reduce wear on bearings, pistons and valve train

These properties ensure long-term operational reliability.


Viscosity & specifications

The correct viscosity class (e.g. multigrade oils) influences

  • Cold start behavior

  • Lubricating film stability at operating temperature

  • Oil consumption

  • Engine efficiency

In addition, manufacturer approvals and API/ACEA specifications must be taken into account to ensure full compatibility.


Selection according to engine, year of manufacture & application profile

The following parameters should be taken into account for a safe selection:

  • Engine type (gasoline or diesel)

  • Displacement and power range

  • Year of manufacture and manufacturer specification

  • Area of use (inland, coastal, continuous operation)

  • Operating profile (short distance, long distance, high load)

Structured adjustment prevents incorrect filling and reduces the risk of engine damage.


Oil change & maintenance

Recommended measures:

  • Check oil level regularly

  • Change the oil according to operating hours or seasonally

  • Replace the oil filter at every change

  • Check used oil for metal abrasion or contamination

Regular maintenance increases service life and operational safety.


Typical damage caused by incorrect engine oil

The use of unsuitable lubricants can lead to

  • Increased bearing and piston wear

  • Deposits in the combustion chamber

  • Insufficient lubrication during temperature changes

  • loss of performance

  • premature engine failure

premature engine failure. The correct choice of oil is therefore a decisive factor for reliability.