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Wärtsilä FuelFlex Injection control unit upgrade for RT-flex engines

Earlier generation Injection Control Units (ICUs) were designed for the operation with residual fuel. Since 2015, Sulphur cap of 0.1% limit was enforced in Emission Controlled Areas (ECA), which is requiring low viscosity fuel oil in use. As consequence, many marine two-stroke engines have encountered issues due to fuel change e.g. frequent fill up of fuel drain tank or premature wear of fuel injection components in ECA operation.

As Global Sulphur cap is introduced in 2020, the challenge of operation with compliant fuels become predominant. In conjunction with maximum worn internal ICU sealing, large fuel leakage toward the fuel injector can occur. Consequently, the fuel is slowly injected even after regular injection period (uncontrolled injection).

ICUs’ malfunction and fuel leakage from high pressure pipe are the top three known failure causes for RT-flex engine injection when operating with compliant fuels, which counted for  up to 70% of unexpected engine stoppages according to received customers’ feedback.

FuelFlex ICU

    Wärtsilä FuelFlex ICU upgrade provides upgrading of earlier generation ICU to the latest ICU type in order to solve the customer’s challenge foreseen by the compliant fuel of the global sulphur cap.

    The upgrade can be installed for the entire engine in one upgrade package, or alternatively step-wise for individual ICUs, whatever best suits the vessel schedule or the ICU maintenance status.

    Wärtsilä FuelFlex ICU upgrade ensures safer engine operation regardless of fuel type in use.


    Wärtsilä FuelFlex ICU - Best reliability with compliant fuels at enhanced maintenance flexibility and reduced life cycle maintenance cost!

    • Enhanced reliability regardless of fuel type in use
    • Reduced risk of unexpected engine stops 
    • Flexibility and solutions for on-board maintenance

    The solution is suitable for all vessels with Wärtsilä RT-flex 96C-B and RT-flex84T-D engine, particularly those operating predominantly or flexibly with compliant fuels.

    Technical Presentation of Wärtsilä FuelFlex ICU 

    Wärtsilä FuelFlex ICU upgrade renews earlier generation ICUs with the latest technology, ensures safer engine operation regardless of the fuel types in use and provides the flexibility to do onboard ICU maintenance.


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    Wärtsilä FuelFlex injection control unit upgrade

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