Experience1969 - 2023 in the marine industry

Marine Engineers and Superintendents Technical Support

Service Letters and Bulletins

for 2-stroke and 4-stroke diesel engines

I have collected on this page MAN and Wartsila important (from my point of view) service letters and bulletins. Read, learn, and carry out recommendation.

Dear marine engineers, the service letters with action code "Immediately", "Casualty" or "At First Opportunity" need your special attention.
Several years ago I participated in investigation. The main reason of damaged was outstanding work according to the MAN service letter SL02-405/CBO "Check of Camshaft Coupling Fitted Bolts All engine types" with action code Immediately. Shipowner had to order two tugs and vessel had towed to Sicily. It was a blessing that it was Mediterranean Sea. Imagine this situation in the middle of the North Atlantic Ocean in winter time or in the middle of Pacific Ocean. It is disaster.

To get a complete set of Service Letters and Bulletins valid for your engine I recommend using MAN diesel & Turbo or Wartsila online service. It is the fastest and most convenient way to get updated and new technical information.

Remember that a service letter takes priority over instructions.

MAN Diesel Service Letter SL11-539/US. January 2011.
Damaged Starting Air Pilot Valve.

Concerns: Owners and operators of MAN B&W two-stroke marine diesel engines. Types: ME/ME-C

starting air pilot valve

Dear Sirs,
We have recently experienced a few failures of the starting air pilot valve and consequently starting problems of the engine. The failures were caused by two factors:

1. Disintegration of the activator piston in the pilot valve.
2. Loosening of the nut for positioning the magnetic coil on the pilot valve.

Re 1
Three types of valves have been used since the introduction of ME/ME-C engines - only the new type is used today, see below.

Maker: Bosch Rexroth
New type:
MAN No. 5158228-5 - Bosch Rexroth
No. R40-406-116-5 (aluminium piston).

Old types:
MAN No. 5057773-8 - Bosch Rexroth
No. R40-405-372-2 (synthetic piston).

MAN No. 1235947-9 - Bosch Rexroth
No. 565/331 (internal pilot air 30 bar).

We recommend inspecting the valves at the earliest opportunity, and check the valves at regular intervals of 12,000 service hours in connection with overhaul of the main starting valve.

Re 2
The finger nut for the magnetic coil should be secured with Loctite 222 to prevent loosening of this component.

Questions or comments regarding this SL should be directed to our Dept. LEO.

Yours faithfully,
Mikael C Jensen (Vice President, Engineering) and Stig B Jakobsen (Senior Manager, Operation)

starting air pilot valve new type
New Type. MAN No. 5158228-5. Bosch Rexroth No. R40-406-116-5 (aluminium piston)

starting air pilot valve old type
Old type. MAN No. 5057773-8. Bosch Rexroth No. R40-405-372-2 (synthetic piston)

starting air pilot valve polyacetal sealing
Damaged synthetic piston (POM: Polyacetal)

Finger nut to be secured with Loctite 222
Finger nut to be secured with Loctite 222

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MAN Diesel Service Letter SL09-510/SBJ. April 2009.
Laying up vessels Preservation of engines for cold laying-up

Concerns: Owners and operators of MAN B&W two-stroke MC/MC-C, ME/ME-C and ME-B marine diesel engines and, furthermore, MAN Diesel four-stroke L16/24, L21/31, L27/38, L32/40, L23/30 (H) and L28/32 (H) marine GenSets.

Dear Sirs
Lately, we have received requests from shipowners about instructions for laying up vessels for an unspecified period of time.
For this purpose, we have drawn up Recommendation No. 0743581-8, which is enclosed. The recommendation deals with the procedure for long term laying up of vessels with the main engine and auxiliary engines out of operation and in cold condition.

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Volcano Company Safety Bulletin. April 2010.
Safety Precaution of Volcano gun type burner Type VJ installed on your auxiliary boiler.

Dear sirs,
We are writing to you concerning an incident recently occurred on our gun type oil burner type VJ that is installed on the auxiliary boiler plant.
We hereby again wish to remind our customers of importance of adhering to safety bulletin, which was sent before by us and has been again enclosed herewith.

1. Incident.
On November18, 2008, auxiliary boiler furnace installing our VJ type oil burner flashed back and a ship's engineer was burned.
The detail is shown in the report issued by Australian Transport Safety Bureau (ASTB).

2. The root cause of the incident.
It is highly likely that the repeated unsuccessful attempts of relighting the burner without eliminating the cause of ignition failure allowed unburned fuel to accumulate until explosive vapor was preset in the furnace. Under such condition, the flashback was caused. (This warning is clearly described in our safety bulletin.)

3. Safety recommendation.
1)We like you to make sure that our safety bulletin sent before by us and enclosed herewith again should be in hand of ship crews who handle a boiler and instruct them to read carefully. If necessary, please arrange necessary training of ship crews for safety operation.
2) We also strongly remind you that the operation and the maintenance service should be done strictly by adhering to the safety bulletin. If not, you will be exposed to the risk of same kind of accident as described in ASTB`s report.

4. Other information.
As per ASTB`s report, we will advice as follows:
We have many types of burners. One of such burners is "direct ignition" type oil burner ,named "VJ" and we have other type of pressure jet type burner fitted with the pilot burner, named "VJP".
If you wish to have a burner fitted with pilot burner, we advise that the existing burner could be replaced with VJP type burner or could be modified.
If you are interested to know how much cost is required for the replacement and how different two models are, we are happy to give you necessary information.

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MAN Diesel Service Letter SL09-515/CXR. September 2009.
Guidelines on Operation on Distillate Fuels
Low-viscosity fuels

Dear Sirs,

With the introduction of new and tighter fuel sulphur content regulations by the EU and the California Air Resources Board, MAN B&W two-stroke engines will increasingly operate on distillate fuels, i.e. marine gas oil (MGO) and marine diesel oil (MDO) in such areas where required.

MAN B&W two-stroke engines are optimised to operate on heavy fuel. However, MGO/MDO fuels can be used when appropriate considerations are made to the following to ensure a safe and reliable performance, i.e.:
- the viscosity and lubricity of the fuel
- keeping a high fuel pump pressure
- the use of a cooler or chiller in an external fuel supply system
- other considerations, references for more information.

This service letter gives guidelines and recommendations on how to ensure a safe and reliable operation on low-viscosity distillate fuels.

ISO 8217.
Influence of lubricity and viscosity.
Fuel oil pump pressure.
Installation of cooler or chiller & cooler.
Other considerations

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Wartsila Service Bulletin RT-82. 29.06.2009
Technical Information to all Owners / Operators of Wärtsilä RTA and RT-flex Engines
Distillate Fuel Use

1 Introduction
2 Minimum fuel viscosity
3 Distillate fuel use
4 Cylinder oil selection
5 Fuel change over procedure
6 Conclusion
7 Layout of fuel oil system
8 ISO 8217 Fuel standard

1 Introduction

Wärtsilä Switzerland allows for its engines to be operated on all fuels supplied under the ISO 8217 specification.

Current and foreseen marine fuel legislation is limited to prescribing the maximum sulphur content or to reduce the sulphur in the exhaust gas with alternative methods equivalently.

The availability of fuels with various sulphur levels is not yet fully clear. However, as the demand for sulphur content in the fuel is reduced below 0.5%, the possibility of distillate fuel increases. In many respects, distillate fuel differs from heavy fuel. In general it must be said that both the quality is more strictly specified and improved combustion characteristics are observed for this fuel type compared to heavy fuels.

According to ISO 8217, distillate fuels are categorised as DMX, DMA (also called MGO) and DMB (often called MDO). DMX is emergency fuel with a lower flashpoint, coming with additional storage precautions. Due to the low flash point, this fuel would not normally be used in marine diesel engines. DMA and DMB are most common distillate fuels and also have guaranteed good combustion characteristics due to the specified cetane index, whereas DMC-fuel contains up to 15% HFO and has no cetane index prescribed.

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Wartsila Service Bulletin RT-18.4. 09.06.2009
Supersedes Bulletin RTA-18.3
Technical Information to all Owners / Operators of Wärtsilä RTA and RT-flex engines
Running-in of Cylinder Liners and Piston Rings

1 Introduction
2 General remarks
3 Preparations and checks to be made before starting the engine
4 Remarks on running-in
5 Running-in with CLU3 system
6 Running-in with Pulse Jet, Retrofit Pulse or Pulse Feed lubrication system
7 Reduction of the feed rate below recommended or guide value
8 Cylinder oil
9 Running-in programmer

1 Introduction
This Service Bulletin provides information regarding the updated running-in procedure for newly fitted piston rings after a piston overhaul or replacement of one or more cylinder liners on an engine in service. These running-in guidelines are based on our experience with material and machining specifications for cylinder liners or piston rings approved by Wärtsilä Switzerland Ltd. It is therefore of the utmost importance that spare cylinder liners and piston rings are genuine Wärtsilä spare parts.

In the Service Bulletin 18.3, only the CLU3 system is explained. This present edition will consider two additional systems, the Pulse Jet and Pulse (Retrofit and Feed) systems, which have a similar running-in procedure. Service Bulletin 60.1 may be referenced for older type lubrication systems.

This document for running-in supersedes all relevant instructions provided in Bulletin 18.3 and Engine Operating Manuals.

2 General remarks
After fitting the new cylinder liners or even after replacing only the piston rings, these must be run-in. The purpose of running-in is to achieve good sealing of the rings as soon as possible and is especially important for non-Chrome-Ceramic rings. Under no circumstances must any seizing occur on the running surfaces of cylinder liner and piston rings.

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Wartsila Service Bulletin RTA-79.1 / RT-flex-08.1. 08.01.2008
Technical Information to all Owners / Operators of RTA and RT-flex Engines
Continuous Low Load Operation (Slow Steaming)

1. Introduction
2. Considerations
3. Recommendations

Engines are optimised for operation in the load range above approximately 60% CMCR. Continuous running at lower loads is possible, but will influence the operational parameters and engine components.

The engine Operating Manual provides guidelines for low load operation. This service Bulletin is intended to give additional recommendations when running the engine continuously at loads lower than "Normal Load" (See Graph below), so called "Slow Steaming". The mentioned recommendations assume operating periods exceeding e.g. the lightering period of tankers or channel passages, and are referring to sea voyages in this load range. The recommendations are made assuming that no components are changed nor engine tuning is modified in order to stay within the limitations imposed by IMO emission regulations. Any further measures require recertification of the engine with new or amended Technical File.

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MAN Diesel Service Letter SL08-498. August 2008.
Spark Erosion Update.
Action Code: Immediately

Unfortunately, spark erosion is still a problem on some vessels with two-stroke marine diesel engines. However; engine design and our recommendations for service and maintenance procedures have changed since our last service letter on spark erosion.

Former MAN Diesel service letters on spark erosion: SL 83-193, SL 86-213, and SL 08-495

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MAN Diesel Service Letter SL07-488/PMN. November 2007.
Work Inside Cylinder Liners

Dear Sirs,

We regret very much having to inform you about an accident that occurred recently on a vessel in Bremerhaven.

During modification work inside the cylinder liner on a K90MC engine, only the exhaust valve had been removed to allow access into the cylinder liner. One fitter was inside the liner when cooling water was admitted by accident, see Encl. 1.

The cooling water entered the combustion chamber from the bores in the cylinder cover, where cooling water passes from the cylinder cover to the exhaust valve.

Further to normal precautious practices and safety procedures, we therefore stress the following:

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MAN Diesel Service Letter SL07-480/SBE. June 2007.
Low Load Operation for MC and ME engines
Long Term Operation Mode

In connection with requests from shipowners asking for guidelines for operating engines with reduced load in order to save fuel, we have prepared this new Service Letter on this issue.

The recommendations are to be considered as overall guidelines based on engine performance including the exhaust gas boiler in general. In case permanent low-load operation of the engine is required, the exhaust gas boiler manufacturer should be consulted for advice, as well.

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Important Service Letters and Bulletins

MAN diesel Service Letters Archive
SL08-495/KNB MC/MC-C and ME/ME-C Type Engines. Condition Based Overhaul of Crank-train Bearings.
SL07-474/JJP Lifting Tool for Crosshead Bearing Cap 80-98MC/MC-C and ME/ME-C Engines.
SL05-460/NHN Crosshead Bearing Condition.
SL04-439/HMH K/L/S-MC/MC-C Engines Instruction books - Standard Tightening Torques.
SL04-437/HNN S60MC-C Engines Lifting of Cylinder Liner.
SL03-420/ERO Crankcase Relief Valves.
SL03-417/HRJ Cylinder Oil Dosage Optimisation S/L/K- MC/MC-C/ME, Mk 6 engines with Alpha Lubricator System.
SL03-415/CSH 60-98MC/MC-C Engines Radial Type Starting Air Distributors.
SL03-415 Attachment.
SL02-412/NIM Fuel Pump Top Cover L/S35MC, S46-50-60-70MC-C (Fuel pumps without VIT).
SL02-407/KEA Control Air for Exhaust Valves.
SL02-405/CBO Check of Camshaft Coupling Fitted Bolts. All engine types.
SL00-383/SBJ 26-98MC/MC-C/MC-S Engines. Removal of Wear Ridges on Cylinder Liners.
SL88-244/UM L50-60-70MC/MCE Engines. Starting Air Distributor.
SL87-223/UM MC/MCE Engines. Super-VIT Fuel Pumps: Adjustment & Maintenance.
Wartsila / Sulzer Service Bulletins Archive
RTA-62 Technical Information to all Owners / Operators of Sulzer RTA Engines. Prevention of Water Carry-Over and Liner Polishing.
RTA-54 Technical Information to all Owners / Operators of Sulzer RTA Engines with Electronic VIT. Electornic Variable Injection Timing Troubles and Remedies.
RTA-50 Technical Information to all Owners / Operators of Sulzer RTA Engines. Leakage Oil Collector in Air Spring System of Exhaust Valve.
RTA-46 Technical Information to all Owners / Operators of Sulzer RTA “-8 and -2 Series” Engines. CRACKS IN COLUMN.
RTA-45 Technical Information to all Owners / Operators of Sulzer RTA Diesel Engines. Tightening Instructions for Screws and Waisted Studs.
RTA-43 Technical Information to all Owners / Operators of Sulzer RTA Engines (except RTA 38 and RTA 48. Piston Rings.
RTA-28 Technical Information to all the Owners of Sulzer RTA Type Diesel Engines equipped with DENIS-1 and DENIS-5 ENGINE CONTROL SYSTEMS. Improvement of the Engine Control System.
RTA-26 Technical Information to all the Owners of Sulzer RTA 58, 68, 76 and 84 Type Engines with WATERCOOLED PISTONS. Loss of Material on Piston Crowns due to High Temperature Corrosion and Erosion.
RTA-23 Technical Information to all the Owners of Sulzer RTA 38 and RTA 48 Type Diesel Engines. Regulation of Cylinder Liner Lubrication.

All names mentioned are registered tradesmen of registered companies and are mentioned for reference only.
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