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Slow-speed engines

Our range of marine cylinder lubricants, Castrol Cyltech has been formulated to deliver 2-stroke engine cleanliness and control deposits.

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Forward in protection, performance and reliability

To protect your slow-speed marine engines, you need specially selected technology that offers you engine performance and operational reliability.

 

Discover the evolved Castrol Cyltech range

Delivering 2-stroke engine cleanliness

The Castrol Cyltech range of cylinder oils has been formulated to deliver 2-stroke engine cleanliness and provide excellent control of piston ring and cylinder liner wear. Our products are available across a range of different base numbers spanning 40 to 140 BN. With approval from the major OEMs, the Cyltech range will meet all you slow-speed needs.  

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Castrol Cyltech range 

Castrol Cyltech 40 XDC

Castrol Cyltech 40 XDC

  • Category II 40 BN cylinder oil*
  • Formulated for increased cleanliness in combustion cylinder
  • Performance equal to or better than a category II 100 BN cylinder oil
  • Approved across all MAN ES engines and recommended for Mark 9 and higher
  • Category II lubricant for LNG and methanol**

No objection letters

  • MAN ES category II
  • Win GD

 

Marine fuels <0.5% sulphur

  • MGO: marine gas oil, <0.1% sulphur (distillate)
  • ULSFO: ultra low sulphur fuel oil, <0.1% sulphur (residual)
  • VLSFO: very low sulphur fuel oil, <0.5% sulphur (residual)
Castrol Cyltech 40SX

Castrol Cyltech 40SX

  • Bespoke detergency system for engine cleanliness
  • Very good overall performance, especially deposit control
  • Excellent performance at optimised feed rates
  • Approved for use in Win GD DF dual fuel engines running on LNG
  • Proven performance on biofuels (B30 and B50)***

No objection letters

  • MAN ES category I
  • Win GD DF
  • JEC

 

Marine fuels <0.5% sulphur

  • MGO: marine gas oil, <0.1% sulphur (distillate)
  • ULSFO: ultra low sulphur fuel oil, <0.1% sulphur (residual)
  • VLSFO: very low sulphur fuel oil, <0.5% sulphur (residual)
Castrol Cyltech 70f

Castrol Cyltech 70f

  • Good performance at high temperatures
  • Lubrication of low speed crosshead engines
  • Suitable for use with compliant fuel and HSFO, subject to OEM recommendations and technical advice

No objection letters

  • MAN ES category I
  • Win GD
  • JEC

 

Marine fuels <0.5% sulphur

  • MGO: marine gas oil, <0.1% sulphur (distillate)
  • ULSFO: ultra low sulphur fuel oil, <0.1% sulphur (residual)
  • VLSFO: very low sulphur fuel oil, <0.5% sulphur (residual)

 

HSFO with scrubbers >0.5% sulphur

  • HSFO: high sulphur fuel oil
Castrol Cyltech 100f

Castrol Cyltech 100f

  • Protection against corrosive wear
  • Excellent control of piston ring and cylinder liner wear
  • Helps extend periods between unit overhauls
  • Granted category II status – latest performance category from  MAN ES

No objection letters

  • MAN ES category II
  • Win GD
  • JEC
     

HSFO with scrubbers >0.5% sulphur

  • HSFO: high sulphur fuel oil
Castrol Cyltech 140

Castrol Cyltech 140

  • Improved protection of cylinder liners in engines operating under corrosive conditions with lower feed rates compared to 100 BN oils
  • Protection against corrosive wear
  • Excellent control of piston ring and cylinder liner wear
  • Granted category II status – latest performance category from  MAN ES

No objection letters

  • MAN ES category II

 

HSFO with scrubbers >0.5% sulphur

  • HSFO: high sulphur fuel oil

Protection, performance and reliability

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Castrol Cyltech has a long history supporting 2-stroke reliability
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Our cylinder oil is trusted by 500+ marine customers
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Used in over 8,000 vessels
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Annually, Cyltech has performed for 34 million voyage hours
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Approvals achieved as a result of 75,000 hours of field testing
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Available in 800 ports worldwide

 

Optimal solutions for 2-stroke engines

Engines face lubrication challenges due to varying fuel sulphur levels, feed rate optimisation requirements and operational conditions. Our range of 2-stroke marine engine lubricants, Castrol Cyltech, provides optimal protection against corrosive and mechanical cylinder wear. 

We have formulated every product in this range with special care to ensure you get the right balance of base numbers (BN) and detergency to protect your engines.

Combine the right product with an active monitoring programme

No two vessels are the same, which means you can’t afford to make assumptions about BN levels across all cylinder lubricants. Castrol Technical Services can help ensure you are using the appropriate lubricant, along with the right feed rate, and monitoring approach to maximize long-term performance. We have got an unbeatable depth of engineering knowledge and skills to work with you on a one-to-one basis. Our SmartGains methodology is designed to maximize the operation and productivity of your asset, prevent unnecessary costs and delays, and optimize the ordering process. And with LabCheck it’s easy for you to get the right data at the right time, identify every potential saving, and minimize unplanned downtime.

* MAN Energy Solutions (MAN ES) no objection letter for category II cylinder oil Cyltech 40 XDC, 40BN, SAE 50 from Castrol. 
** Tests were performed as per the MAN ES category II approval process and Castrol Cyltech 40 XDC was recommended for use with MAN B&W two-stroke engines Mark 9 and higher. Different engine types and different engine operation conditions may require different cylinder lubrication feed rates and or oil type. 
*** Based on no harms vessel trials carried out by bp on B30 and B50 biofuel blends with residual fuel (VLSFO) lubricated by Castrol Cyltech 40SX. 
† Source: Clarksons Research. Based on vessels using Castrol Cyltech products and time spent in sector-specific speed ranges data basis vessel movements data, estimated on an individual vessel basis and averaged for the vessels in the sectors specified for period 2022-2024. Data basis vessels in the fleet only in the period specified. 
 
Speed range for containerships, MPPs, ro-ros, car carriers, reefers, cruise ships, LNG carriers 9-26 knots, for PSVs and utility support 6-50 knots, for passenger ferries 9-50 knots and for other sectors 6-19 knots. 2024 YTD data basis vessel movements up to and including 19 Novemner 2024. 
Data subject to variations in vessel movements data coverage.