Mercury 300R HD CMS Mechanical Operation And Maintenance Manual
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Mercury 300R HD CMS Mechanical Operation And Maintenance Manual

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  • Page 1 Operation Maintenance Manual...
  • Page 3 Thank you for purchasing one of our products. We sincerely hope your boating will be pleasant! Mercury Marine, Fond du Lac, Wisconsin, U.S.A. Name / function: John Pfeifer, President, Mercury Marine...
  • Page 4 Warranty Message The product you have purchased comes with a limited warranty from Mercury Marine; the terms of the warranty are set forth in the Warranty Manual included with the product. The Warranty Manual contains a description of what is...
  • Page 5 Copyright and Trademark Information © MERCURY MARINE. All rights reserved. Reproduction in whole or in part without permission is prohibited. Alpha, Axius, Bravo One, Bravo Two, Bravo Three, GO BOLDLY., Circle M with Waves Logo, K‑planes, Mariner, MerCathode, MerCruiser, Mercury, Mercury...

  • Page 7: Table Of Contents

    General Information Boater's Responsibilities..................1 Before Operating Your Outboard................ 1 Boat Horsepower Capacity................. 1 High‑Speed and High‑Performance Boat Operation.......... 2 Propeller Selection....................2 Outboard Remote Control Models ..............4 Lanyard Stop Switch................... 5 Protecting People in the Water................7 Passenger Safety Message ‑ Pontoon Boats and Deck Boats......8 Wave and Wake Jumping...................
  • Page 8 Operation Important Daily Inspection Before Each Use ........... 36 Prestarting Check List..................36 Operating in Freezing Temperatures..............36 Operating in Saltwater or Polluted Water............37 Operating at High Elevations................37 Effects of Elevation and Weather on Performance........... 37 Setting Trim Angle while Running Engine at Idle Speed........38 Engine Break‑in Procedure................
  • Page 9 Storage Storage Preparation..................81 Protecting External Outboard Components............81 Protecting Internal Engine Components............82 Gearcase......................82 Positioning Outboard for Storage..............82 Battery Storage....................82 Troubleshooting Starter Motor Will Not Crank the Engine............83 Engine Will Not Start..................83 Engine Runs Erratically..................83 Performance Loss.....................
  • Page 10 viii...

  • Page 11: General Information

    GENERAL INFORMATION Boater's Responsibilities The operator (driver) is responsible for the correct and safe operation of the boat and the safety of its occupants and general public. It is strongly recommended that each operator read and understand this entire manual before operating the outboard.

  • Page 12: High-Speed And High-Performance Boat Operation

    When choosing a propeller, a full selection of aluminum and stainless steel propellers specifically designed for your outboard are available through Mercury Marine. To view the entire product offering and find the correct propeller that is best suited for your application, visit www.mercmarinepropellers.com or see your local authorized Mercury dealer.
  • Page 13 GENERAL INFORMATION IMPORTANT: To ensure proper fit, and performance, Mercury Marine recommends the use of Mercury or Quicksilver branded propellers and mounting hardware. Propellers are designated by the diameter, pitch, number of blades, and material. The diameter and pitch are stamped (cast) into the side or the end of the propeller hub.

  • Page 14: Outboard Remote Control Models

    PROPELLER MATERIAL Most propellers manufactured by Mercury Marine are made from either aluminum or stainless steel. Aluminum is suitable for general purpose use and is standard equipment on many new boats. Stainless steel is over five times more durable than aluminum and typically provides performance gains in acceleration and top end speed due to design efficiencies.

  • Page 15: Lanyard Stop Switch

    GENERAL INFORMATION Lanyard Stop Switch The purpose of a lanyard stop switch is to turn off the engine when the operator moves far enough away from the operator's position (as in accidental ejection from the operator's position) to activate the switch. Tiller handle outboards and some remote control units are equipped with a lanyard stop switch.
  • Page 16 GENERAL INFORMATION Important Safety Information: The purpose of a lanyard stop switch is to stop the engine when the operator moves far enough away from the operator's position to activate the switch. This would occur if the operator accidentally falls overboard or moves within the boat a sufficient distance from the operator's position.

  • Page 17: Protecting People In The Water

    GENERAL INFORMATION KEEP THE LANYARD STOP SWITCH AND LANYARD CORD IN GOOD OPERATING CONDITION Before each use, check to ensure the lanyard stop switch works properly. Start the engine and stop it by pulling the lanyard cord. If the engine does not stop, have the switch repaired before operating the boat.

  • Page 18: Passenger Safety Message - Pontoon Boats And Deck Boats

    GENERAL INFORMATION Passenger Safety Message ‑ Pontoon Boats and Deck Boats Whenever the boat is in motion, observe the location of all passengers. Do not allow any passengers to stand or use seats other than those designated for traveling faster than idle speed. A sudden reduction in boat speed, such as plunging into a large wave or wake, a sudden throttle reduction, or a sharp change of boat direction, could throw them over the front of the boat.

  • Page 19: Wave And Wake Jumping

    GENERAL INFORMATION Any unexpected, sudden reduction in boat speed could result in the elevated passenger falling over the front of the boat. 26783 Wave and Wake Jumping Operating recreational boats over waves and wake is a natural part of boating. However, when this activity is done with sufficient speed to force the boat hull partially or completely out of the water, certain hazards arise, particularly when the boat enters the water.

  • Page 20: Impact With Underwater Hazards

    GENERAL INFORMATION Impact with Underwater Hazards Your outboard is equipped with a hydraulic trim and tilt system that also contains a shock absorbing feature. This feature helps the outboard withstand damage in the case of impact with an underwater object at low to moderate speeds.

  • Page 21: Exhaust Emissions

    Operating a boat or engine with impact damage can result in product damage, serious injury, or death. If the vessel experiences any form of impact, have an authorized Mercury Marine dealer inspect and repair the vessel or power package. Exhaust Emissions...
  • Page 22 GENERAL INFORMATION STAY CLEAR OF EXHAUST AREAS 41127 Engine exhaust gases contain harmful carbon monoxide. Avoid areas of concentrated engine exhaust gases. When engines are running, keep swimmers away from the boat, and do not sit, lie, or stand on swim platforms or boarding ladders.

  • Page 23: Selecting Accessories For Your Outboard

    Some accessories not manufactured or sold by Mercury Marine are not designed to be safely used with your power package and may void warranty. Acquire and read the installation and operation manuals for each selected accessory.
  • Page 24 GENERAL INFORMATION • We recommend that all powerboat operators complete a boating safety course. In the U.S., the U.S. Coast Guard Auxiliary, the Power Squadron, the Red Cross, and your state or provincial boating law enforcement agency provide courses. For more information in the U.S., call the Boat U.S.
  • Page 25 (refer to your boat's capacity plate). Know your boat's operating and loading limitations. Know if your boat will float if it is full of water. When in doubt, contact your authorized Mercury Marine dealer or the boat manufacturer. Ensure that everyone in the boat is properly seated.

  • Page 26: Recording Serial Number

    GENERAL INFORMATION • Boat operators are required by law to file a boating accident report with their state boating law enforcement agency when their boat is involved in certain boating accidents. A boating accident must be reported if 1) there is loss of life or probable loss of life, 2) there is personal injury requiring medical treatment beyond first aid, 3) there is damage to boats or other property where the damage value exceeds $500.00, or 4) there is...

  • Page 27: Specifications-300R Hd

    GENERAL INFORMATION Specifications—300R HD 300R HD MODELS Attribute 300R HD Horsepower Kilowatts Full throttle RPM range 5800–6400 Idle RPM in neutral gear* Idle charge compensation** 600–725 Troll control RPM limit 550–1000 Number of cylinders 4.6 Liter Displacement 4,576 cc (279.2 cid) Cylinder bore 92 mm (3.62 in.) Stroke...
  • Page 28 ***Battery manufacturers may rate and test their batteries to different standards. MCA, CCA, Ah, and reserve capacity (RC) are the ratings recognized by Mercury Marine. Manufacturers that use standards different than these, such as equivalent MCA, do not meet Mercury Marine battery requirements.

  • Page 29: Component Identification

    GENERAL INFORMATION Component Identification 66302 Service access door Top cowl Engine flush Auxiliary tilt switch Cooling water intake holes External steering bracket (dealer installed option or factory installation available) Water pump indicator hole Engine oil drain Exhaust relief...

  • Page 30: Gearcase Identification

    GENERAL INFORMATION Gearcase Identification Diameter Identification Illustration or Type Features Water intake— eight per side, four torpedo low water 137 mm Left‑hand rotation (5.4 in.) gearcase—LL stamped on the end of propeller shaft 64308 Water intake— three torpedo low water Sport Left‑hand rotation Master...

  • Page 31: Transporting

    TRANSPORTING Trailering Boat/Outboard The best position to trailer your boat is with the outboard tilted down in a vertical operating position. If additional ground clearance is required, the outboard should be tilted up using an accessory outboard support device. Refer to your local dealer for recommendations.

  • Page 32: Fuel And Oil

    USA is alcohol (ethanol, methanol, or butanol). GASOLINE CONTAINING ALCOHOL Bu16 Butanol Fuel Blends Fuel blends of up to 16.1% butanol (Bu16) that meet the published Mercury Marine fuel rating requirements are an acceptable substitute for unleaded gasoline. Contact your boat manufacturer for specific recommendations on your boat's fuel system components (fuel tanks, fuel lines, and fittings).

  • Page 33: Fuel Additives

    Fuel Additives To minimize carbon deposit buildup in the engine, it is recommended to add Mercury or Quicksilver Quickstor fuel stabilizer additive to the engine's fuel at each tank fill throughout the boating season. Use additive as directed on container.

  • Page 34: Engine Oil Recommendations-Race (R) Models

    IMPORTANT: The use of nondetergent oils, multiviscosity oils (other than Mercury or Quicksilver NMMA FC‑W certified oil or a major brand NMMA FC‑W certified oil), full synthetic oils, low quality oils, or oils that contain solid additives are not recommended.
  • Page 35 FUEL AND OIL IMPORTANT: Do not overfill. Tilt the outboard out/up past vertical for approximately one minute to allow trapped oil to drain back to the oil sump. The outboard must be in a vertical (not tilted) position when checking the engine oil. For accurate readings, check the oil only when the engine is cold or after the engine has not run for at least an hour.
  • Page 36 FUEL AND OIL 4. Remove the dipstick and observe the area of the five beads. 63305 Service access door Oil fill cap Dipstick 5. The bead or crosshatch which shows oil furthest from the end is the oil level. 65509 Oil level example NOTE: New oil (level) may be difficult to identify which is why the crosshatch between the beads are part of the dipstick assembly.
  • Page 37 FUEL AND OIL IMPORTANT: Repeated removal and insertion of the dipstick will subsequently deposit oil further up the dipstick tube which potentially may cause an error reading the oil level. 65510 Safe operating range General area after an oil change Add 1.8 Liter (2 US qt) of oil 6.

  • Page 38: Features And Controls

    Remote Control Features Your boat may be equipped with one of the Mercury Precision or Quicksilver remote controls shown. If not, consult your dealer for a description of the functions and operations of the remote control.
  • Page 39 FEATURES AND CONTROLS 1. Continuous six second beep: Indicates a critical engine condition. Depending on the condition, the Engine Guardian system may engage and protect the engine by limiting power. You should return to port immediately and contact your servicing dealer. 2.
  • Page 40 SMARTCRAFT PRODUCT A Mercury SmartCraft System instrument package can be purchased for this outboard. A few of the functions the instrument package will display are engine RPM, coolant temperature, oil pressure, water pressure, battery voltage, fuel consumption, and engine operating hours.

  • Page 41: Power Trim And Tilt

    FEATURES AND CONTROLS LOSS OF SHIFT COMMAND When the Engine Guardian system detects a loss of shift control (fault code 339‑23), the warning horn will beep and the engine RPM will be limited. SmartCraft gauges which have the ability to display text will alert the operator with a short text, long text, and the action which the operator should follow.
  • Page 42 FEATURES AND CONTROLS NOTE: Exceeding 4250 RPMs the engine PCM will begin Engine Guardian protection. 63388 Trim switch Tilt range Trim range POWER TRIM OPERATION With most boats, operating around the middle of the trim range will give satisfactory results. However, to take full advantage of the trimming capability there may be times when you choose to trim your outboard all the way in or out.
  • Page 43 FEATURES AND CONTROLS • Increase steering torque or pull to the right (with the normal right‑hand rotation propeller) • In excess, can lower the bow of some boats to a point where they begin to plow with their bow in the water while on plane. This can result in an unexpected turn in either direction (called bow steering or oversteering) if any turn is attempted, or if a significant wave is encountered.
  • Page 44 FEATURES AND CONTROLS TRIM LIMIT PIN (SINGLE-RAM TRIM) WARNING Operating the boat at high speeds with the outboard trimmed too far under can create excessive bow steer, resulting in the operator losing control of the boat. Install the trim limit pin in a position that prevents excessive trim under and operate the boat in a safe manner.
  • Page 45 FEATURES AND CONTROLS NOTE: Exceeding 4250 RPMs the engine PCM will begin Engine Guardian protection.

  • Page 46: Operation

    OPERATION Important Daily Inspection Before Each Use Any outboard mounted on the boat must have the mounting hardware inspected and checked to ensure that the hardware has not become loose. A decal on the transom bracket reminds the owner to check the fasteners securing the outboard to the transom before each use.

  • Page 47: Operating In Saltwater Or Polluted Water

    Wash the outboard exterior and flush out the exhaust outlet of the propeller and gearcase with fresh water after each use. Each month, spray Mercury Precision or Quicksilver Corrosion Guard on external metal surfaces. Do not spray on corrosion control anodes as this will reduce the effectiveness of the anodes.

  • Page 48: Setting Trim Angle While Running Engine At Idle Speed

    OPERATION • High humidity These conditions above reduce air density to the engine, which in turn lowers the following: • Boost pressure on supercharged engines • Horsepower and torque throughout the RPM range • Peak RPM • Cranking compression EXAMPLE: An engine running at an elevation of 8,000 feet will have over a 30% power loss while a loss of engine power on a hot and humid day could be as much as 14%.

  • Page 49: Engine Break-In Procedure

    OPERATION Engine Break‑in Procedure IMPORTANT: Failure to follow the engine break‑in procedures can result in poor performance throughout the life of the engine and can cause engine damage. Always follow break‑in procedures. 1. For the first two hours of operation, run the engine at varied throttle settings up to 4500 RPM or at three‑quarter throttle, and at full throttle for approximately one minute every ten minutes.
  • Page 50 OPERATION NOTE: If the outboard fuel system does not prime within 15 key ON events, check for leaks in the fuel supply line to the outboard. Repair as needed. If no leak is found, the fuel supply system to the outboard may be too restrictive. Correct the condition and try again.

  • Page 51: Starting The Engine

    OPERATION Starting the Engine Before starting, read the Prestarting Check List, and Engine Break‑in Procedure in this section. NOTICE Without sufficient cooling water, the engine, the water pump, and other components will overheat and suffer damage. Provide a sufficient supply of water to the water inlets during operation.
  • Page 52 OPERATION 2. Check the engine oil level. Refer to Fuel and Oil ‑ Checking and Adding Engine Oil. 63305 Service access door Oil fill cap Dipstick 3. Ensure that the cooling water intake is submerged. 66310...
  • Page 53 OPERATION 4. Set the lanyard stop switch to the RUN position. Refer to General Information ‑ Lanyard Stop Switch. 19791 5. Shift the outboard to neutral (N) position. 58237 6. Ignition key starting ‑ Turn the ignition key to the START position and release the key.

  • Page 54: Gear Shifting

    OPERATION IMPORTANT: If no water is coming out of the water pump indicator hole, stop the engine and check the cooling water intake for obstruction. No obstruction may indicate a water pump failure or blockage in the cooling system. These conditions will cause the engine to overheat.

  • Page 55: Stopping The Engine

    OPERATION Stopping the Engine Reduce the engine speed and shift the outboard to neutral position. Turn the ignition key to "OFF" position. 26843...

  • Page 56: Maintenance

    Record maintenance performed in the Maintenance Log at the back of this book. Save all maintenance work orders and receipts. Selecting Replacement Parts For Your Outboard We recommend using original Mercury Precision or Quicksilver replacement parts and Genuine Lubricants. DO NOT USE CAUSTIC CLEANING CHEMICALS IMPORTANT: Do not use caustic cleaning chemicals on the outboard power package.
  • Page 57 Keep water spray out of the air filter/intake and alternator. After washing, allow the powerhead and components to dry. Apply Quicksilver or Mercury Precision Lubricants Corrosion Guard spray on the external metal surfaces of the powerhead and powerhead components. Do not allow the Corrosion Guard spray to come in contact with the alternator drive belt or belt pulleys.

  • Page 58: Epa Emissions Regulations

    EPA Emissions Regulations All new outboards manufactured by Mercury Marine are certified to the United States Environmental Protection Agency, as conforming to the requirements of the regulations for the control of air pollution from new outboard motors. This certification is contingent on certain adjustments set to factory standards.

  • Page 59: Inspection And Maintenance Schedule

    MAINTENANCE The owner/operator is not to modify the engine in any manner that would alter the horsepower or allow emission levels to exceed their predetermined factory specifications. Inspection and Maintenance Schedule BEFORE EACH USE • Check engine oil level. Refer to Checking Engine Oil Level. •...
  • Page 60 MAINTENANCE • Change engine oil and replace the oil filter. The oil should be changed more often when the engine is operated under adverse conditions, such as extended trolling. Refer to Changing Engine Oil and Filter. • Check the engine mounted water‑separating low‑pressure fuel filter for water or contaminants.

  • Page 61: 300R Hd Models Maintenance Schedule Decal

    MAINTENANCE • Check cowl seals to ensure seals are intact and not damaged. • Check that the intake silencer is in place, if equipped. • Check that the idle relief muffler is in place, if equipped. • Check for loose hose clamps and rubber boots on the air intake assembly, if equipped.

  • Page 62: Flushing The Cooling System

    MAINTENANCE Flushing the Cooling System Flush the internal water passages of the outboard with fresh water after each use in salt, polluted, or muddy water. This will help prevent a buildup of deposits from clogging the internal water passages. NOTE: The outboard can be tilted or in the vertical operating position during flushing.
  • Page 63 MAINTENANCE 2. Push down on the port side of the service access door to unlock and open the door. 64230 Push here to unlock 3. Press on the red lock button and lift the handle. Service access door Red lock button Handle 63306...

  • Page 64: Battery Inspection

    MAINTENANCE 4. Push the handle towards the aft to lock the handle into the cowl lift position. 63308 Handle locked in the lift position 5. With a firm grip on the handle, carefully lift the cowl off the engine. INSTALLATION 1.

  • Page 65: Battery Cables And Clean Power Harness

    MAINTENANCE 3. Battery cable terminals should be clean, tight, and correctly installed. Positive to positive and negative to negative. 4. Ensure the battery is equipped with a nonconductive shield to prevent accidental shorting of battery terminals. Battery Cables and Clean Power Harness The battery cable connections should be checked often for corrosion or loose retaining hardware.
  • Page 66 MAINTENANCE IMPORTANT: An ATC fuse has the fuse element enclosed or sealed inside the plastic housing. This type of fuse must be used for marine applications. Marine applications are exposed to environments that may have the potential to accumulate explosive vapors. ATO fuses have exposed elements and should never be used in marine applications.

  • Page 67: Fuel System

    MAINTENANCE Fuel System WARNING Fuel is flammable and explosive. Ensure that the key switch is off and the lanyard is positioned so that the engine cannot start. Do not smoke or allow sources of spark or open flame in the area while servicing. Keep the work area well ventilated and avoid prolonged exposure to vapors.
  • Page 68 MAINTENANCE 4. Push in on the fuel hose release tabs and disconnect the fuel hoses from the fuel filter. 5. Disconnect the water‑in‑fuel sensor harness. NOTE: If there is a boat mounted water‑separating fuel filter with a water‑in‑fuel sensor installed, the sensor harness would be connected to the boat mounted filter.

  • Page 69: Corrosion Control Anode

    MAINTENANCE 8. Wipe up any spilled fuel. Installation 1. Apply a small amount of 2‑4‑C with PTFE to the fuel filter grommet. 63416 Tube Ref Description Where Used Part No. 2-4-C with PTFE Fuel filter grommet 92-802859A 1 2. Install the fuel filter and rotate counterclockwise 1/4 turn to retain the filter. 3.

  • Page 70: Propeller Replacement-31.75 Mm (1-1/4 In.) Diameter Propeller Shaft

    3. Pull the propeller straight off the shaft. If the propeller is seized to the shaft and cannot be removed, have the propeller removed by an authorized dealer. 4. To aid in future removal of the propeller, liberally coat the propeller shaft splines with one of the following Mercury/Quicksilver products:...

  • Page 71: Spark Plug Inspection And Replacement

    MAINTENANCE Tube Ref Description Where Used Part No. Extreme Grease Propeller shaft splines 8M0071842 2-4-C with PTFE Propeller shaft splines 92-802859A 1 NOTE: Propellers used on the 31.75 mm (1‑1/4 in.) diameter propeller shaft require the heavy‑duty propeller hub kit. 5.
  • Page 72 MAINTENANCE 2. Grasp the spark plug boot and use a twisting motion to assist removing the spark plug boot from the spark plugs. 63312 Spark plug boot 3. Remove the spark plug with a 14 mm deep socket. NOTE: Replace the spark plug if the electrode is worn; the insulator is rough, cracked, broken, or blistered;...
  • Page 73 MAINTENANCE 4. Check the spark plug gap. Refer to General Information ‑ Specification. 27848 a. All of the spark plugs should have the gap checked and corrected as necessary before installation. b. Measure the gap with a feeler gauge or pin gauge. Never use a wedge‑type gap checking tool to inspect or to adjust the gap.

  • Page 74: Fuses

    MAINTENANCE 8. Push on the end of the spark plug boot to ensure the boot is completely engaged and seated onto the spark plug. 63315 Push the spark plug boot 9. Install the top cowl. Fuses IMPORTANT: An ATC fuse has the fuse element enclosed or sealed inside the plastic housing.
  • Page 75 MAINTENANCE 1. Locate the fuse holder on the port side of the engine and remove the cover from the fuse holder. 63317 2. Remove the suspected open fuse and look at the silver band inside the fuse. If the band is broken (open), replace the fuse.

  • Page 76: Alternator Drive Belt

    Alternator Drive Belt The alternator drive belt is located under the flywheel shroud–intake air induction plenum. The alternator drive belt inspection must be completed by an authorized Mercury dealer at the recommended interval. Refer to Inspection and Maintenance Schedule. Lubrication Points 1.
  • Page 77 MAINTENANCE Tube Ref Description Where Used Part No. Swivel bracket, tilt lock, tilt tube, 2-4-C with PTFE 92-802859A 1 propeller shaft • Lubricate the tilt lock through the grease fitting. • Lubricate the swivel bracket through the grease fitting. Tilt lock grease fitting Swivel bracket grease fitting 66320 •...

  • Page 78: Trim Thrust Guide Wear Pad

    MAINTENANCE • Propeller shaft—Refer to Propeller Replacement for removal and installation of the propeller. Apply a generous amount of lubricant to the entire propeller shaft to prevent the propeller hub from seizing to the shaft. 66448 2. Lubricate the steering linkage with oil. 63797 Lubricate with oil Trim Thrust Guide Wear Pad...

  • Page 79: Checking Power Trim Fluid (Single-Ram Trim)

    MAINTENANCE IMPORTANT: When replacing the thrust guide wear pads, replace both pads and install new retaining hardware. 66265 Checking Power Trim Fluid (Single‑Ram Trim) 1. Trim the outboard in the full down/in position. 2. Check the fluid level in the trim pump reservoir. The level should be between the minimum ("MIN") and the maximum ("MAX") level on the reservoir.

  • Page 80: Checking Hydraulic Steering Fluid

    MAINTENANCE Tube Ref Description Where Used Part No. Power Trim and Trim pump reservoir 92-858074K01 Steering Fluid 4. Trim the outboard full up and down to purge air out of the system. The fluid level may drop. Add Power Trim and Steering Fluid if necessary, but do not overfill past the maximum level.

  • Page 81: Changing Engine Oil And Filter

    MAINTENANCE Remove the power steering cover and fill cap to check the fluid level. The fluid level should be slightly below the bottom of the fill hole. Use Synthetic Power Steering Fluid SAE 0W‑30, if needed. 29315 Power steering cover Fill cap Fill/full level Tube Ref...
  • Page 82 MAINTENANCE IMPORTANT: Do not loosen the oil drain valve more than 2‑1/2 turns out. The oil seal could get damaged beyond 2‑1/2 turns. 63398 Oil drain valve Drain hose Loosen 2‑1/2 turns maximum 6. After the oil has drained, hand‑tighten the oil drain valve (clockwise) and remove the oil drain hose.
  • Page 83 MAINTENANCE 3. Push down on the port side of the service access door to unlock and open the door. 64230 Push here to unlock 4. Remove the dipstick. 5. Install the oil drain hose onto the crankcase oil pump. Verify the hose is securely attached.
  • Page 84 MAINTENANCE Crankcase Oil Pump 802889A1 Aids in the removal of engine oil without draining the crankcase. 11591 Oil Drain Hose 8M0137866 Aids in the removal of engine oil without draining the crankcase. Connect to the crankcase oil pump. 64627 6. Install the crankcase oil pump assembly onto the dipstick tube. Verify the pump is securely attached to the tube by pulling it up lightly.
  • Page 85 MAINTENANCE 11. Install the dipstick. Verify it is completely inserted. 12. Add the appropriate amount of engine oil. CHANGING OIL FILTER 1. Remove the plug from the oil trough and attach a 12 mm (7/16 in.) I.D. drain hose to the fitting. Place the opposite end of the hose into an appropriate container.

  • Page 86: Checking Engine Oil Level

    MAINTENANCE NOTE: It is not necessary to check the oil level immediately after changing the oil. The engine must be run for a while and then turned off for one hour or longer before checking the oil level. Refer to Checking Engine Oil Level. Checking Engine Oil Level After the engine oil has been changed, the engine should be run for a few minutes and then turned off, allowing one hour or longer before checking the oil...

  • Page 87: Exhaust Water Strainer Inspection

    MAINTENANCE Exhaust Water Strainer Inspection IMPORTANT: The water strainer is an integral component of the cooling system. It should be inspected every 100 hours of operation or once a year, whichever occurs first. 1. Remove the top cowl. Refer to Top Cowl Removal and Installation. 2.

  • Page 88: Gearcase Lubricant

    MAINTENANCE 4. Inspect the strainer for debris, blockage, or accumulation of mineral deposits. Flush the strainer with fresh water. Use a nylon bristle brush to help remove debris, blockage, or mineral deposits. If the strainer cannot be cleared of debris, blockage, mineral deposits, or if the strainer is damaged, replace the strainer.
  • Page 89 MAINTENANCE 4. Remove the lubricant level plug and fill/drain plug. Allow a sufficient amount of time for the gearcase to drain. Depending on the ambient air temperature, it may take 30 minutes for the gearcase to completely drain. Lubricant level plug Fill/drain plug 66264 Filling the Gearcase...
  • Page 90 MAINTENANCE 5. Remove the lubricant tube and install the fill/drain plug and sealing washer. 6. Tighten the plugs to the specified torque. Description lb‑in. lb‑ft Plugs 11.3 –...

  • Page 91: Storage Preparation

    Stabilizer Protecting External Outboard Components • Touch up any paint nicks. See your dealer for touch‑up paint. • Spray Quicksilver or Mercury Precision Lubricants Corrosion Guard on external metal surfaces (except corrosion control anodes). Tube Ref Description Where Used Part No.

  • Page 92: Protecting Internal Engine Components

    STORAGE Protecting Internal Engine Components IMPORTANT: Refer to Maintenance ‑ Spark Plug Inspection and Replacement for correct procedure for removing spark plugs. • Remove the high tension spark plug leads and spark plugs. • Spray approximately 30 ml (1 fl oz) of Storage Seal Rust Inhibitor into each spark plug hole.

  • Page 93: Troubleshooting

    TROUBLESHOOTING Starter Motor Will Not Crank the Engine POSSIBLE CAUSES • Lanyard stop switch not in RUN position. • Open 20‑amp fuse. Check the power driver fuse. Refer to Maintenance section. • Outboard is not shifted to neutral position. • Weak battery or battery connections are loose or corroded.

  • Page 94: Performance Loss

    TROUBLESHOOTING • Ignition system component failure. Performance Loss POSSIBLE CAUSES • Overheating ‑ Warning horn not working. • Low oil pressure. Check oil level. • Throttle not opening fully. • Damaged propeller or improper propeller size. • Incorrect engine timing, adjustment, or setup. •...

  • Page 95: Owner Service Assistance

    STOLEN POWER PACKAGE If your power package is stolen, immediately advise the local authorities and Mercury Marine of the model and serial numbers and to whom the recovery is to be reported. This information is maintained in a database at Mercury Marine to aid authorities and dealers in the recovery of stolen power packages.
  • Page 96 OWNER SERVICE ASSISTANCE RESOLVING A PROBLEM Satisfaction with your Mercury product is important to your dealer and to us. If you ever have a problem, question or concern about your power package, contact your dealer or any authorized Mercury dealership. If you need additional assistance: 1.

  • Page 97: Ordering Literature

    Before ordering literature, have the following information about your power package available: Model Serial Number Horsepower Year UNITED STATES AND CANADA For additional literature for your Mercury Marine power package, contact your nearest Mercury Marine dealer or contact: Mercury Marine Telephone Mail Mercury Marine (920) 929‑5110 (920) 929‑4894...
  • Page 98 OWNER SERVICE ASSISTANCE Mercury Marine Submit the following Attn: Publications Department order form with payment W6250 Pioneer Road P.O. Box 1939 Fond du Lac, WI 54936-1939 Ship To: (Copy this form and print or type–This is your shipping label) Name...

  • Page 99: Maintenance Log

    MAINTENANCE LOG Maintenance Log Record all maintenance performed on your outboard here. Be sure to save all work orders and receipts. Date Maintenance Performed Engine Hours...

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