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BUKH V8 engines are quality inspected and tested before they leave the BUKH factory. The BUKH V8 engine has been tested on a high power engine test bench, to assure that torque and power is in accordance with BUKH specifications.
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Please ensure sufficient sea water cooling flow. Break in procedure The BUKH V8 series engines need break-in time before being operating to its full potential. This is due to the design characteristics of the base engine. Follow the recommendations below:...
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Do oil and filter change after the engine has run a total of 30 hours. Use oil and filter as specified in BUKH V8 Maintenance book. This is highly important! If you have any questions regarding this break-in procedure please consult the technical department at your local BUKH dealership or BUKH.
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Winter storage • Oil system Change oil on the supercharger. Drain the oil from the engine, either by removing the oil plug in the oil pan or by a suction tube down the dipstick tube; remember it’s always recommended to do this when the engine is at operating temperature. Tighten the plug, clean the oil dipstick and reinsert it in the tube.
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• Electrical System Remove and clean the battery/batteries. Also clean the battery cables and connecting poles. Store battery in a cold/dry ventilated environment (never below 0ᵒC/32F) and keep it fully charged. Procedures after winter storage • Exhaust System Remove all winter-storage-seals from exhaust and intake system. •...
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To retain the dependability, noise and exhaust emission control originally built into all BUKH V8 (further on referred to as BUKH or V8) engines, it is essential that the engines are installed according to the V8 installation instructions and receive periodic maintenance according to the V8 maintenance book.
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User’s Manual. 2. Damage resulting from accident, acts of nature or other events beyond the control of BUKH or any of its representatives. 3. The replacement of expendable maintenance items such as exhaust system, filters, hoses, belts, oil, thermostat, and coolant made in connection with scheduled maintenance services once these parts have been replaced.
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The following is a list of items that are considered a part of the Emission Control Systems and are covered by the Emission Warranty when installed as original equipment by BUKH on engines which were built to conform to Environmental Protection Agency regulations.
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The center exhaust has one inner exhaust chamber and a surrounding coolant chamber for sea water. Exhaust and sea water, exits the BUKH V8 engine through 2 outlets and mixes into an Ø120 mm outlet. Picture show the exhaust manifolds.
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This is a bonded stainless steel mesh filter material and should be cleaned and replaced according to service intervals. See BUKH V8 MAINTENANCE BOOK. The air filter element mounts to the intake runner inlet with a clamp. Air filter unit...
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Variable geometry turbo assembly The turbocharger assembly information can be found in BUKH V8 manual. Below is an explanation of some interacting parts. Turbo charger Description Picture of the turbo charger. The charger is a high quality turbo charger in stainless steel.
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Sea water inlet Description Picture of impeller pump and sea water inlet. Ø40 mm hose connection Owners Manual...
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Diesel fuel in/out. Description Picture of a diesel fuel inlet and fuel outlet. Diesel fuel IN is Inlet from fuel tank pump. Outside Ø12 mm tube. Recommended 2-3 bar and max 44 ᵒC Return Out is a Ø10 mm tube Picture of inlet fuel cooler.
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The return fuel must pass via the fuel cooler before returning to the tank. Raw water connection is on the impeller pump on the lower starboard side of the engine. Please see appropriate sections for further information. Oil filter It is essential that the oil lines and oil filter are prefilled with oil before starting the engine. The lines should be connected as shown below.
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Oil hoses Description Picture of oil hose connections with remote engine oil filter and oil cooler. 1. From oil pump, out connection, to nearest oil cooler connection. 2. From oil cooler to oil in arrow, on remote oil filter house. 3.
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WARNING BEFORE MOUNTING THE OIL FILTER, FILL THE OIL FILTER COMPLETELY WITH OIL. THIS IS TO ENSURE THAT THE ENGINE GETS LUBRICATED DIRECT FROM START-UP. Owners Manual...
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Engine Mounting The engine bed provides a location for the engine and associated marine gear to be mounted, if it is not mounted directly on boat stringers. The engine bed or stringers should be constructed in such way as to allow even weight distribution and load transfer.
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Flexible Engine Mounting BUKH offers BUKH V8 heavy duty & SOLAS flexible mounting for all BUKH V8 series engines. All front mounts include provisions for isolating engine vibrations. The rear of the engine mounts to the stern drive transom plate or transmission.
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The engine can then be lifted into position, in boat using an overhead hoist. To allow for final adjustments, please mount the optional, BUKH V8 flexible mountings with shims underneath. Owners Manual...
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Power Steering Hose Routing When installing power steering hoses observe the following. • Make hydraulic connections as quickly as possible to prevent fluid leakage. • Be careful not to cross-thread or over tighten fittings. Power steering fluid hoses must be purchased separately. Proper routing and installation of the hoses is required to avoid problems related to power steering system.
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Exhaust Hose Routing General Information All exhaust systems have some restriction to flow, or what is called “exhaust back pressure”, but this must remain at a minimum. The power output of an engine is directly related to the amount of exhaust that can flow out of the exhaust system.
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Through the Hull Exhaust When designing and installing an exhaust system, in addition to other model specific requirements, BUKH requires the following to be observed: • Exhaust fittings (flanges and outlets) must be of proper size • Exhaust fittings must be equipped with internal water shutters.
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Engine Compartment WARNING Boating standards (NMMA, ABYC, etc.) and Coast Guard regulations must be adhered when constructing the engine compartment. Engine Compartment Ventilation General Information According to Boating standards (NMMA, ABYC, etc.) and Coast Guard regulations the engine compartment ventilation system has multiple tasks. Including: •...
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A - Air should exit the engine bay at the upper section B - Air should enter the engine bay at the lower section The reason for this is that hot air is lighter than cold air and will exit at the top of the compartment. Once the engine is shut down such a system will auto ventilate until the engine bay temperature is at ambient level.
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1.7 X Rated engine power in KW and given in cm Conversion factor from HP to KW is ~ 0.735. Example for BUKH V8 - 500: Recommended open ventilation area, for combustion air only is: 1.7 x 500 HP x 0,735 ~ 620 cm For engine combustion air only - NOT total engine compartment ventilation requirement.
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Section 3 – FUEL DELIVERY SYSTEM Fuel Delivery System Fuel Tank Fuel Lines Additional Fuel Filter Usage Fuel Line Fitting Installation Fuel Return Fitting Requirements Water Separating Fuel Filter Fuel System Temperature and Pressure Drop Owners Manual...
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The fuel system, from the filler pipe to the fuel pump, is the same in principle for all boats. Fuel Tank The fuel tank is an integrated component of the boat. BUKH makes no attempt in this manual to cover all aspects of design and integration of the fuel tank in the boat due to the broad range of possible configurations.
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• Keep short horizontal distance, between the fuel tank and the fuel inlet fitting on the engine. • BUKH offers a suitable optional fuel pump. • Consider an anti-siphon device. • Keep fuel tube length between top of the fuel tank and fuel inlet fitting on engine as short as possible.
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• A flexible fuel line must be used to connect fuel supply line to fuel inlet fitting on engine to absorb deflection when engine is running. • An anti-siphon device (valve) is required. An electric solenoid anti-siphon device is one of the least restrictive and is allowed by the Coast Guard.
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Fuel Line Fitting Installation IMPORTANT: The following information is provided to ensure proper installation of brass fittings or plugs installed into fuel pump or fuel filter base: • Apply 592 Loctite Pipe Sealant on threads of brass fittings or plugs. DO NOT USE TEFLON TAPE.
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Fuel System Temperature and Pressure The engine power output can be limited by restrictions in the boat’s fuel supply system. The V8 specifications for the boat’s fuel system performance regarding fuel inlet are: Specifications For Fuel System Performance Maximum Fuel Inlet Temperature Maximum Fuel Pressure Drop.
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Section 4 – COOLING SYSTEM Cooling System Seawater Supply and Hose Connections Through The Hull or Transom Seacock Seawater Filter Seawater Pump and Bracket Drive Belt Routing Water Heaters Owners Manual...
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Cooling System BUKH V8 engines have two separate cooling systems. First cooling system is a sea water cooling system. Second cooling system is a closed loop cooling system with antifreeze coolant. Cooling system components must be constructed and sized appropriately to supply the engine with sufficient sea water under all operating conditions.
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Through the Hull or Transom On the engine the seawater cooling hose connects to a water pickup that is mounted through the hull or transom of the boat. Refer to instructions provided by the seawater pickup manufacturer, or Installation Manual supplied with product. A seacock (water inlet valve) is recommended. A through the hull or through the transom seawater pickup, must have an internal cross sectional area equal to or greater than seawater inlet hose to prevent restricting water flow.
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Through the Sterndrive Unit Seawater inlet hose through sterndrive is NOT recommended. Any resulting engine overheat problems will NOT be covered by BUKH warranty. Through the Hull or Transom Seawater pickup hose must be obtained separately if using a through the hull or through the transom seawater pickup.
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Seawater Filter Strainer used, if equipped, must be of sufficient size to ensure that an adequate supply of water will be maintained for cooling the engine. (Refer to specifications in this document) Seawater strainer should be installed in an area where it will be easily accessible for inspection and cleaning.
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Drive Belt Routing Drive belt routing Description The drive belt routing on one configuration of a BUKH V8 series engine. Owners Manual...
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Drive Belt Routing Configurations BUKH V8 without Power Steering BUKH V8 with Power Steering Owners Manual...
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To install a water heater or cabin heater you must purchase the optional water heater tube available from BUKH. This will replace the original bypass tube installed on the engine. If the optional tube is installed you must circulate water to the external heater and back to the engine or the engine can overheat thus voiding warranty.
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Section 5 – BATTERY and CONTROL Battery Battery Cables Accessories ECU and Relay Box Warnings System and Alarms Control Panel Owners Manual...
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• 12 V marine type. • Tapered post connectors or side terminal connectors are required. • Battery required capacity rating and CCA depends on engine usage. SOLAS, commercial or leisure conditions? The local BUKH service partner can guide you. Owners Manual...
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Battery Cables Battery cable gauge will change based on the length of the cable needed. Be sure to measure the length of the battery cables from battery to engine so the gauge can be determined by the chart below. Select proper gauge (size) positive (+) and negative (–) battery cables, using chart: Starter cable.
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Accessories Up to 3 accessory leads can be connected to the positive battery terminal (B+) stud on the starter motor. These leads must be equipped with the appropriate current overload protection. Refer to the ABYC standards or applicable industry standards for more information. Do not attach any accessory ground (-) wires to engine block Accessory ground wires should only be attached to ground terminal (-) on battery.
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ECU and Relay Box Description Picture of ECU, Engine Control Unit. A plug is located on the engine ECU bracket. This will allow the instrumentation wiring harness to be connected to the engine wiring harness. Picture of relay box. Relay box Description Picture of relay box after black cap is removed.
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Warning System If warning system is activated, immediately shut down the engine by turning the key to off position. Control Panel Control panel Description Picture of control panel. Panel with red emergency stop. Ignition key and engine data display screen. Please mount control panel covered from rain and vapour.
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Section 6 – PRE DELIVERY PREPARATION Pre Delivery Preparation Battery Connection Power Steering Boat-in-the-Water Test Engine Idle Speed Wide Open Throttle Test Important Installation Notes Pre Delivery Checklist Cold Weather or Extended Storage Draining Instructions Owners Manual...
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Pre Delivery Preparation Once the engine package installation is complete, the following final steps should be taken to prepare engine package for delivery to the customer. It is the boat manufacturer’s responsibility to perform these procedures, or to make arrangement with the dealer to have these procedures completed.
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Power Steering Use only automatic transmission fluid (ATF) in power steering system. CAUTION Do not run power steering dry. Pump will be damaged. 1. Position drive unit so that it is straight back. 2. Remove fill cap from power steering pump reservoir and check fluid level. 3.
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Boat-in-the-Water Test CAUTION Avoid engine damage. Ensure that cooling water is supplied to the engine if it will be operated with the boat out of the water. Engine Idle Speed Engine should idle at 600-700 rpm. with engine at normal operating temperature. If idle speed is incorrect and the vessel has an external throttle lever, proceed as follows: 1.
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Common Cause of Problems • Please make careful notes on mounting battery cables of the correct dimensions, failure to comply with this will make the engine difficult to start. • Engines are shipped without oil, make sure you fill the engine with oil and check the level before starting.
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We have found that adding the through hull inlet ensures adequate water flow to the engine and prevents issues arising in the future. The BUKH warranty does NOT cover engine overheat related problems.
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Please see BUKH V8 Official Warranty Information and hand in a warranty registration form on www.bukh.dk Owners Manual...
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Cold Weather or Extended Storage CAUTION If the engine will not be used for an extended period of time or will be exposed to freezing temperatures, drain water from seawater section of cooling system. Water MUST BE drained to prevent corrosion and freeze damage to engine. CAUTION If boat is to remain in the water, seacock, if so equipped, must remain closed until engine is to be restarted to prevent water from flowing back into seawater cooling system.
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