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Break-In Procedures

The first 10 hours of operation are critical. Following these steps protects your warranty — skipping them is the #1 cause of repeat failures.

Lower Unit & Sterndrive

  1. Gearcase assemblies are shipped without oil. Fill with the manufacturer's required gear oil to the recommended level.
  2. Adjust RPM at idle to manufacturer's specifications.
  3. Proper shift adjustment is essential.
  4. Avoid full-throttle starts.
  5. Shift into forward gear a minimum of 10 times during break-in, with moderate engine speed after each shift.
  6. Do NOT operate at constant speed for extended periods.
  7. Do NOT exceed 75% of full throttle during the first five hours of operation.
  8. During the next 5 hours, full throttle should not be maintained for long periods.

⚠ Jumping out of gear: if the unit will not stay in gear, the clutch dog has probably been rounded off. Rounded clutch dogs are caused by — but not limited to — improper shift cable adjustment, inadequate shift travel, idle RPM set too high, or shifting too slowly. Rounded clutch dogs are NOT covered by warranty.

⚠ OMC and Mercruiser sterndrive service notice: when purchasing either an upper or lower assembly separately, the opposite piece must be disassembled and cleaned by the service center in order to validate the warranty. This provision is due to cross-contamination of the oil.

Powerhead Break-In Procedures

The first 10 hours

  1. Do NOT perform break-in on a water hose.
  2. Double your oil with a major manufacturer TCW-3 oil (excludes direct-injected engines).
  3. Use a mid-grade octane major manufacturer fuel without alcohol.
  4. Liquid-cooled engines should be slowly brought up to normal operating temperature to avoid cold seizure.
  5. 1st hour: operate the engine at a varied speed of 700–1500 RPM to break in new pistons and rings.
  6. Next 6 hours: operate the engine in gear at no more than 3,000 RPM. Accelerate using only enough throttle to bring the boat up on plane quickly and back off to maintain minimum plane speed.
  7. Vary engine speed by accelerating to 3/4 throttle for 1–2 minutes, then back to minimum plane speed.
  8. Final 3 hours: you may operate the boat at wide-open throttle for periods of less than 2 minutes.
  9. Cylinder heads should be re-torqued after the 10-hour break-in period.

⚠ Avoid the danger zone: avoid operating at a constant speed of 3,000–4,000 RPM or continuous full throttle for the first 10 hours. This is the economy range where the timing is at full advance and the carburetor or fuel injection is running lean — which can lead to overheating and piston detonation.

Powerheads

Avoiding repeat failure

This powerhead is replacing one that failed prematurely. Powerhead failure is usually due to excessive combustion chamber temperature — you must find the cause or the same problem will occur again. In our experience, the piston is usually the first part to fail, typically from detonation. These tips help you avoid a repeat:

  1. Have all injectors cleaned and flow-tested. Replace injectors that are out of spec.
  2. Check the entire fuel system, including fuel pump, line filters, and carburetors.
  3. Increase main metering jets by .002.
  4. Retard ignition timing by 2 degrees.
  5. Replace or check all switch boxes and ignition modules.
  6. On Mercury motors, remove the idle stabilizer and advance module.
  7. Verify high and low fuel pressures are within specification.

Carbureted OMC-Johnson-Evinrude

  1. Install .002 larger main jets in carburetors.
  2. Retard maximum timing 2 degrees. Set max timing with engine running over 4,500 RPM under load. Do NOT set max timing static.
  3. Replace water pump and gaskets at the time of powerhead replacement and every year. Use the newest-style gaskets.
  4. On 3-cylinder engines, replace the water pump with the late-model high-pressure style. Check all OMC service bulletins and jet carburetors accordingly.
  5. We recommend installing a water pressure gauge to monitor water flow in the engine.
  6. Use mid-grade octane major manufacturer fuel without alcohol.
  7. We recommend removing the oil injection system or updating to the latest VRO pump.
  8. Clean and refill oil tank with TCW-3 oil.
  9. Verify oil consumption by marking the oil tank during the double-oil break-in period.
  10. Double your oil with a major manufacturer TCW-3 oil for approximately 30 gallons of fuel. If running oil injection, add 1 pint of oil to 6 gallons of gas. If no oil injection, add 1 quart of oil to 6 gallons of gas. Does NOT apply to direct-injected motors.
  11. Re-torque cylinder heads after one hour of running time, after the engine has cooled.
  12. Rebuild carburetors and/or fuel pump.
  13. Check overheat and oil alarm horn for proper function.

Carbureted & EFI Mercury V6

  1. Install .002 larger main jets in carburetors.
  2. Rebuild or replace carburetors and fuel pump.
  3. Retard maximum timing 2 degrees.
  4. Remove advance module and idle stabilizer if present on the motor.
  5. Replace water pump and all gaskets at the time of powerhead replacement and every year. Use the newest-style gaskets.
  6. Use a mid-grade octane major manufacturer fuel without alcohol.
  7. We recommend removing the oil injection system. If oil injection is used, replace the 2-PSI oil valve and check oil pump bushing and seal.
  8. Clean and refill oil tank with TCW-3 oil. Verify oil consumption by marking the oil tank.
  9. Make sure trigger wires on the flywheel are free-moving for proper advance.
  10. Re-torque 2.0 / 2.4 / 2.5 cylinder heads to 40 ft. lbs. after 1 hour of running time, after the engine has cooled.
  11. Check overheat alarm system and horn. Beware of problems with the detonation sensor and module.
  12. On 2.5 EFI engines, there are as many as seven fuel filters. Remove the cone-shaped filter in the line below the electric pump. Verify fuel pressure is to specification.
  13. Check all latest factory specifications and service bulletins.

4-Stroke Powerhead Break-In

It is critical to thoroughly clean the midsection and oil pan to avoid contaminating the new powerhead or cylinder head. Complete removal of the oil pan is recommended.

⚠ Failures from contaminated oil are NOT covered: change the oil and oil filter after the first 30 minutes of running on a test tank — this removes many of the contaminants left in the oiling system. Failures due to oil-system contamination are not covered under warranty.

  1. 1st hour: operate the engine at varying speeds up to 2,000 RPM (approximately ½ throttle).
  2. 2nd hour: increase the engine speed until the boat is on plane, avoiding full throttle. Back off the throttle while keeping the boat at a planing speed.
  3. Next 8 hours: run the engine at any safe speed, but avoid operating at full throttle for more than five (5) minutes at a time.
  4. After the first 10 hours of use, change the oil and oil filter. After this service, operate the engine normally.

Oil pump notes

  • All Yamaha 3.3L F200 / F225 / F250 shortblocks require oil pump 6P2-13300-00-00 (YA-282)
  • All Yamaha 2.7L F150 shortblocks require oil pump 63P-13300-02-00 (YA-281)

Always use premium oil as recommended by the OEM manufacturer.

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