WESTERBEKE L25 Marine Diesel Engine Service Repair Technical Manual !

TECHNICAL MANUAL WESTERBEKE L25 Marine Diesel Engine PUBLICATION 19419 EDITION 3 MAY 1978 'WESTERBEKE J WESTERBEKECORPORATION • MYLES STANDISH INDUSTRIAL PARK 150 JOHN HANCOCK ROAD, TAUNTON, MA 02780-7319 Downloaded from www.Manualslib.com manuals search engine

SECTION INDEX GENERAL. Introduction Operation Installation Maintenance ENGINE OVERHAUL OTHER OVERHAUL Marine Engine Electrical System Cooling System (External) Transmissions GENERATOR SETS HYDRAULIC CRANKING SYSTEM SERVICE BULLETINS 3 Downloaded from www.Manualslib.com manuals search engine

4 YOUR NOTES Downloaded from www.Manualslib.com manuals search engine

INTRODUCTION 5 IMPORTANT THIS MANUAL IS A DETAILED GUIDE TO THE INSTALLATION, START-UP, OPERATION AND MAINTENANCE OF YOUR WESTERBEKE MARINE DIESEL ENGINE. THE INFORMA- TION IT CONTAINS IS VITAL TO THE ENGINE'S DEPENDABLE, LONG TERM OPERA- TION. READ IT KEEP IT IN A SAFE PLACE KEEP IT HANDY FOR REFERENCE AT ALL TIMES FAILURE TO DO SO WILL INVITE SERIOUS RISK, NOT ONLY TO YOUR INVESTMENT, BUT YOUR SAFETY AS WELL. UNDERSTANDING THE DIESEL •••• The diesel engine closely resembles the gasoline engine inasmuch as the mechanism is essentially the same. Its cylinders are arranged above its closed crankcase; its crankshaft is of the same general type as that of a gasoline engine; it has the same sort of valves, camshaft, pistons, connecting rods, lubricating system and reverse and reduction gear. Therefore, it.follows to a great extent that a diesel engine requires the same preventative maintenance as that which any intelligent operator would give to a gasoline engine. The most important factors are proper maintenance of the fuel, lubricating and cooling systems. Replacement of fuel and lubricating filter elements at the time periods specified is a must, and frequent checking for contamination (i.e. water, sediment etc.) in the fuel system is also essential. Another important factor is the use of the same brand of "high detergent" diesel lubricating oil designed specifically for diesel engines. The diesel engine does differ from the gasoline engine, however, in the method of handling and firing its fuel. The carbu- retor and ignition systems are done away with and in their place is a single component - the Fuel Injection Pump - which performs the function of both. Unremitting care and attention at the factory have resulted in a Westerbeke engine capable of many thousands of hours of dependable service. What the manufact- urer cannot control, however, is the treatment it receives in service. This part rests with you! ORDERING PARTS Whenever replacement parts are needed, always include the complete part descrip- tion and part number (see separate Parts List furnished, if not part of this publication). Be sure to include the engine's model and serial number. Also be sure to insist upon Westerbeke factory packaged parts, because "will fit" parts are frequently not made to the same specifications as original equipment. GENERATOR SETS Westerbeke diesels are used for both the propulsion of boats and for generating electrical power. For generator set app- lications, all details of this Manual apply, except in regard to certain por- tions of the Installation, Operation and Maintenance sections. Additional infor- mation is provided in the section titled Generator Sets, Section T. Downloaded from www.Manualslib.com manuals search engine

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INSTALLATION 7 FOREWORD Since the boats in which these engines are used are many and varied, details of engine installation are equally so. It is not the purpose of this section to advise boatyards and engine installers on the generally well understood and well developed procedures for installation of engines. However, the following outline of general procedure is included because it is valuable in explaining the functions of each component, the reasons why, the precautions to be watched and the relationship of the installation to the operation of the engine. There are details of the installation which should have a periodic check and of which the operator should have a thorough understanding to insure good operating conditions for the engine and correct procedure for its servicing. INSPECTION OF EQUIPMENT The engine is shipped from the factory mounted securely and properly crated. Ac- cessory equipment is shipped in a separate small box, usually packed with the engine crate. Before accepting shipment from the transportation company, the crate should be opened and an inspection made for con- cealed damage. If either visible or con- cealed damage is noted, you should require the delivering agent to sign "Received in damaged condition". Also check contents of the shipment against the packing list and make sure note is made of any discrep- ancies. This is your protection against loss or damage. Claims for loss or damage must be made to the carrier, not to J. H. Westerbeke Corporation. RIGGING AND LIFTING The engine is fitted with lifting rings. Rope or chain slings should be attached to the rings and the engine lifted by means of tackle attached to this sling. The lifting rings have been designed to carry the full weight of the engine, therefore auxiliary slings are not re- quired or desired. CAUTION: Slings must not be so .short as to place the engine lifting eyes in sig- nificant sheer stress. Strain on the engine lifting eyes must not be in excess of 100 from the vertical. A spacer bar must be placed between the two lifting eyes, if supported by valve cover studs. The general rule in moving engines is to see that all equipment used is amply strong and firmly fixed in place. Move the engine a little at a time and see that it is firmly supported. Eliminate possibility of accidents by avoiding haste. Do not lift from the propeller coupling, or pry against this with crowbar, as you may distort the coupling. In some cases it may be necessary to lift the engine in other than the regular horizontal position. It may be that the engine must be lowered endwise through a small hatchway which cannot be made larger. If the opening is extremely restricted it is possible to reduce, to some extent, the outside clearances such as generator, cooling piping, water tank, filters, mounting lugs, etc. This accessory equipment should be removed by a competent mechanic and special care should be taken to avoid damage to any exposed parts and to avoid dirt entering openings. The parts which have been removed should be returned to position as soon as the restriction has been passed. In case it is necessary to hoist the engine either front end upwards or reverse gear .end upwards, the attachment of slings must be done very carefully to avoid the possibility of damage to the parts on which the weight may bear. It is best if special rigging work be done by someone experienced and competent in the handling of heavy machinery. ENGINE BOLTS It is recommended that bronze hanger bolts of appropriate size be used through the engine flexible mounts. Lag screws are less preferred because their hold on the wood is weakened every time they are moved, whereas the lag bolt stays in position and the nut on top is used to tight- en the engine down or is removed to permit the engine to be lifted. The bolt itself stays in position at all times, as a stud, and the bond between the bolt and the wood is not weakened by its removal. Downloaded from www.Manualslib.com manuals search engine

8 FOUNDATION FOR ENGINE A good engine bed contributes much toward the satisfactory operation of the engine. The engine bed must be of rigid construction and neither deflect nor twist when subjected to the engine weight or the position the boat may have to take under the effects of rough seas. The bed must keep the engine within one or two thous- andths of an inch of this position at all times. It has to withstand the forward push of the propeller which is applied to the propeller shaft, to the thrust washer bearing in the engine and finally to the engine bolts and engine bed. In fiberglas hulls, we recommend that similar wooden stringers as in wooden hulls be formed and fitted, then glassed to the hull securely. This allows hanger bolts to be installed firmly in wood, thus reducing noise and transmitted vibration. The temptation to install the engine on a pair of fiberglas "angle irons" should be resisted. Such construction will allow engine vibrations to pass through to the hull. Flexible mounts require a firm foundation against which to react if they are to do their job. When possible, follow bed design "A" and avoid bed design "B". PROPELLER COUPLING Each Westerbeke Diesel engine is regu- larly fitted with a suitable coupling for connecting the propeller shaft to the engine. The coupling must not only transmit the power of the engine to turn the shaft, but must also transmit the thrust either ahead or astern from the shaft to the thrust bearing which is built into the reduction gear housing of the engine. This coupling is very carefully machined for accurate fit. For all engine models, a propeller half- coupling, bored to shaft size for the specific order, is supplied. The coupling either has a keyway with set screws or is ot the clamping type. The forward end of the propeller shaft has a long straight keyway. Any burrs should be removed from the shaft end. The coupling should be a light drive fit on the shaft and the shaft should not have to be scraped down or filed in order to get a fit. It is important that the key be properly fitted both to the shaft and the coupling. The key should fit the side of the keyway very closely, but should not touch the top of the keyway in the hub of the coupling. If it seems difficult to drive the coupling over the shaft, the coupling can be expanded by heating in a pail of boil- ing water. The face of the propeller coupling must be exactly perpendicular to the centerline or axis of the propeller shaft. PROPELLER The type and size of propeller varies with the gear ratio and must be selected to fit the application based upon boat tests. To utilize the full power of the engine, and to achieve ideal loading conditions, it is desirable to use a propeller which will permit the engine to reach its full rated speed at full throttle under normal load. ALIGNMENT OF ENGINE The engine must be properly and exactly aligned with the propeller shaft. No matter what material is used to build a boat it will be found to be flexible to some extent and the boat hull will change its shape to a greater extent than is usually realized when it is launched and operated in the water. It is therefore very important to check the engine align- Downloaded from www.Manualslib.com manuals search engine

ment at frequent intervals and to correct any errors when they may appear. Misalignment between the engine and the propeller shaft is the cause of troubles which are blamed often on other causes. It will create excessive bearing wear, rapid shaft wear and will, in many cases, reduce the life of the hull by loosening. the hull fastenings. A bent propeller shaft will have exactly the same effect and it is therefore necessary that the propeller shaft itself be perfectly straight. One particularly annoying result of misalignment may be leakage of transmission oil through the rear oil seal. Check to make sure that alignment is within the limits prescribed. The engine should be moved around on the bed and supported on the screw-jacks or shims until the two halves of the coup- lings can be brought together without using force and so that the flanges meet evenly all around. It is best not to drill the foundation for the foundation bolts until the approximate alignment has been accu- rately determined. Never attempt a final alignment with the boat on land. The boat should be in the water and have had an opportunity to assume its final water form. It is best to do the alignment with the fuel and water tank about half full and all the usual equipment on board and after the main mast has been stepped and final rigging has been accomplished. Take .plenty of time in making this alignment and do not be satisfied with anything less than perfect results. The alignment is correct when the shaft can be slipped backwards and forward into the counterbore very easily and when a feeler gauge indicates that the flanges come exactly together at all points. The two halves of the propeller coupling should be parallel within 0.002 inches (A). i \ .. 9 In making the final check for alignment, the engine half coupling should be held in one position and the alignment with the propeller coupling tested with the propeller coupling in each of four positions, rotated 90 0 between each position. This test will also check whether the propeller half coupling is in exact alignment on its shaft .. Then, keeping the propeller coupling in one position the alignment should be checked rotating the engine half coupling to full position each 900 from the next one. The engine alignment should be rechecked after the boat has been in service for one to three weeks and, if necessary, the alignment remade. It will usually be found that the engine is no longer in alignment. This in not because the work was improperly done at first, but because the boat has taken some time to take its final shape and the engine bed and engine stringers have probably absorbed some moisture. It may even be necessary to re- align at a further period. The coupling should always be opened up and the bolts removed whenever the boat is hauled out or moved from the land to the water, and during storage in a cradle. The flexibility of the boat often puts a very severe strain on the shaft or the coupling or both when it is being moved. In some cases the shaft has actually been bent by these strains. This does not apply to small boats that are hauled out of the water when not in use, unless they are dry for a considerable time. EXHAUST SYSTEM Exhaust line installations vary consid- erably and each must be designed for the particular job. The general requirements are to provide an outlet line with a mini- mum of restrictions and arranged so that sea water, rain water, or condensation cannot get back into the engine. There should be a considerable fall in the line between the exhaust manifold flange and the discharge end. This slope in the pipe makes it difficult for water to be driven in very far by a wave; and a steep drop followed by a long slope is better than a straight gradual slope. Avoid any depres- sion or trough to the line which would fill with water and obstruct the flow of exhaust gas. Also avoid any sharp bends. Brass or copper is not acceptable for wet exhaust systems, as the combination of salt water and diesel exhaust gas will Downloaded from www.Manualslib.com manuals search engine

10 cause rapid deterioration. Galvanized iron fittings and galvanized iron pipe is recommended for the exhaust line. The exhaust line must be at least as large as the engine exhaust manifold flange and be increased in size if there is an especial- ly long run and/or many elbows. It should be increased by 1/2" in LD. for every 10 feet beyond the first 10 feet. EXHAUST SYSTEM WITH WATER JACKETED STANDPIPE To insure vibration doesn't transmit to hull, use a flexible section preferably of stainless steel, no less than 12" overall, threaded at each end and installed as close to the engine as possible. This flexible section should be installed with no bends and covered with insulating material. The exhaust pipe should be properly supported by brackets to eliminate any strain on the manifold flange studs. Many installations use flexible rubber exhaust hose for the water cooled section of the exhaust line because of the ease of installation and flexibility. Provide adequate 1-)/10" 0.0, ,-''''. ___ !--... 11·1/2" OIA. MUF'FLEA., PH 1)1710 WATER LIFT EXHAUST SYSTEM WITH "HYDRO-HUSH" MUFFLER support for the rubber hose to prevent sagging, bending, and formation of water pockets. Always arrange that water discharge into the rubber hose section is behind a riser or sufficiently below the exhaust flange so that water cannot possibly flow back into the engine. Also make sure that entering sea water cannot spray directly against the inside of the exhaust piping. Otherwise excessive erosion will occur. MEASURING EXHAUST GAS BACK PRESSURE Back pressure must be measured on a straight section of the exhaust line and as near as possible to the engine exhaust manifold. The engine should be run at maximum load during the measurement period. Set-up should be as shown below. 1. For normally asperated engines: Pressure Test Mercury Test Water Column 1-1/2" Max PSI 3" Mercury = 39" 2. For turbo-charged engines: Pressure Test Mercury Test 0.75 Max PSI 1-1/2" Mercury Checking The Back Pressure 1. Exhaust pipe flange 2. Exhaust line Water Column = 19-1/2" 3. Transparent plastic hose, partly filled with water. Measurement "A" may not exceed 39" for normally asperated engines and 19.5" for turbo-charged engines. WATER CONNECTIONS Seacocks and strainers should be of the full flow type at least one size greater than the inlet thread of the sea water pump. The strainer should be of the type which may be withdrawn for cleaning while the vessel is at sea. Water lines can be copper tubing or wire-wound, reinforced rubber hose. In Downloaded from www.Manualslib.com manuals search engine

WESTERBEKE L25 Marine Diesel Engine Service Repair Technical Manual !

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