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ME-GI service experience

This paper describes in detail the service experience of ME-GI, ME-GIE and ME LGIM engines. Furthermore, the latest experience from our large bore engines is described. Technologies to meet Tier III requirements, and our new TCEV/FBIV designs are also touched upon

0.50% S fuel operation 2020

This paper provides information and guidance on 0.50% S fuel operation and how to prepare for the change from operation on high-sulphur fuel to 0.50% S fuel. Attention is drawn to specific fuel properties that should be in focus and how 0.50% S fuels affect the equipment on board. Expectations for the new types of fuels are given, and information on biofuels, fuel testing, and fuels that are not fit for purpose is also included.

Engineering the future two-stroke green-ammonia engine

Green ammonia produced from renewable sources is a strong candidate to a future compliant fuel.This paper describes the development, benefits and application of the future ammonia-propulsion solution which includes: the MAN B&W two-stroke engine designed to operate on ammonia, the LFSS, and even two-stroke ammonia-fuelled gensets.


This Service Letter was written to inform our customers of exhaust gas back pressure for HiMSEN engines with regard to SOx Scrubber installation in order to comply with IMO MARPOL ANNEX VI Reg.14.8 which is to come into force as of 1st January 2020.
Basically, there is no influence when the back pressure is below than 300mmWC for all HiMSEN engine as the engine has been originally designed for maximum allowable back pressure of 300mmWC. In case that the back pressure is increased over the allowable limit due to installation of scrubber, generally increased back pressure causes the deterioration of engine performance.


Updated instruction for indicator valves. By following precautionary measures and actions as recommended by MAN Diesel & Turbo increased safety and reliability
can be achieved.

SL2018-665/MET SOX scrubber retrofit

This Service Letter informs about the impact and required action if an owner/operator decides to retrofit a SOX scrubber on an MAN

Guidelines for Operation on Fuels with less than 0.1% Sulphur

This paper is a guideline for owners, operators and crews on how to prepare for the changes in fuel characteristics and how to operate in compliance with the new sulphur limits in sulphur emission control areas (SECA) as of 1 January 2015. The SECAs currently included are the Baltic Sea, The North Sea, the English Channel and waters within 200 nautical miles from the coast of USA, the coastal waters around Puerto Rico and the U.S. Virgin Islands (the US Caribbean ECA) and Canada.

Service Letter SL2016-636/JWJ Splash Guarding

Based on our experience from visits on board seagoing vessels, where we have seen fuel oil (FO) connections with either incomplete or even missing splash guarding, we would like to draw your attention to installation of the required splash guarding of flanged connections in the FO
and lubricating oil (LO) system.

SL2016-621/CLN Lifetime of Fixed Cylinder Pressure Sensors

High-quality pressure measurements and a long sensor lifetime can be achieved with the proper precautionary measures and actions recommended by MAN Diesel & Turbo.

Black Spots -Cylinder liner with black lacquer and cold corrosion

Wartsila Guide for condition of relevant piston-running components
(liner, pistons and piston rings) Version 2,1 June 2014.

Stern Tube Seals Operation of AFT Seal Tank

The purpose of this bulletin is to provide operating instructions of AFT seal tank and the purpose of AFT seal tank installation.

Load Dependent Cylinder Liner (LDCL) Cooling Water System

Cylinder liner cold corrosion is counteracted by raising the temperature of the exposed parts of the cylinder liner within permissible limits by making modifications to the cylinder liner design and by making changes of the cooling water system.
The latter is done by introducing the new Load Dependent Cylinder Liner (LDCL) cooling water system.


Occasionally patches of black deposits appear on the cylinder liner wall of 2-stroke engines. The black spots may appear anywhere on the cylinder liner running surface. New cylinder liners with still honing marks (plateau honing) present seem to have a stronger tendency for black lacquer formation.


DUQ1-003E Troubleshoot of remote control system

Whenever the troubles for the remote control system have occurred the cause of trouble to be checked by suitable process not to be checked at random. This service information is made based on the trouble which have been reported in the past from many delivered ships.

SL2016-627/MIKA Tightening of Roller Guide Housing

MAN Diesel & Turbo has received reports of incidents of the roller guide housing in service. Such incidents often lead to consequential damage to the frame surface on which the housing is fixed.

SL2016-632/AAB Alpha Lubricator Service Experience

This service letter applies to MAN B&W two-stroke marine diesel engines of the MC/MC-C type.
Furthermore, the aim of the service letter is to address the service issues that have come to our attention, as well as to introduce service kits for the Alpha lubrication system.

SL2017-648/JNN New Gasket Material for Roller Guide Housing

With SL2016-627 we introduced a 10 mm washer and longer installation bolts for the roller guide housing as a preventive measure to reduce the risk of incidents caused by insuffi cient tightening of the installation bolts. A few roller guide housing incidents have been reported even after introduction of the above-mentioned washer and bolt update.

L2017-649/JNN Checking and cleaning of condensate drain trap in charge air drain system

The amount of condensate water during operation may be considerable, and must be given special attention when operating in areas with
high humidity as well as under tropical conditions. For estimation of the condensate amount in relation to the actual operation condition, we
refer to our attached descriptions 502.05 and 602.05.

DUQ1-176E Piston Ring Specifications for Modern Engines

With the increasing engine power and the recent change in the situation for engine operation, for example, popularization of low load operation, reducing cylinder oil consumption, degrading heavy fuel oil, and so on, required performance of piston ring becomes increasingly sophisticated.

DUQ1-184E Cylinder Liner Calibration

In order to estimate piston running condition and/or determine suitable overhauling interval of cylinder liner, it is very important to understand exact trends of cylinder liner wear. There is a possibility that erroneous liner wear data by an improper measurement leads to a misjudgment about cylinder liner condition.