Re: 20Hr check-up
Below is a copy and past from a Mercruiser OEM owners manual. PN 90-864195071 AUGUST 2007 in case your dealer want to check it. Merc stopped the long 20 service years ago, now it's only engine oil and filter, and drive oil. You should also have received a like owners manual with your new engine/drive setup. It comes with it. You should also have an isntallation CD in the packet also. If not, your dealer must have kept it.
20‑Hour Break‑In Period
IMPORTANT: The first 20 hours of operation is the engine break‑in period. Correct break‑in is essential to obtain minimum oil consumption and maximum engine performance. During this break‑in period, the following rules must be observed:
• Do not operate below 1500 RPM for extended periods of time for the first 10 hours. Shift into gear as soon as possible after starting and advance the throttle above 1500 rpm if conditions permit safe operation.
• Do not operate at one speed consistently for extended periods.
• Do not exceed 3/4 throttle during the first 10 hours. During the next 10 hours, occasional operation at full throttle is permissible (5 minutes at a time maximum).
• Avoid full throttle acceleration from idle speed.
• Do not operate at full throttle until the engine reaches normal operating temperature.
• Frequently check engine oil level. Add oil as needed. It is normal for oil consumption to be high during the break‑in period.
After Break‑In Period
To help extend the life of your Mercury MerCruiser power package, the following recommendations should be considered;
• Ensure that propeller allows the engine to operate at or near the top of the specified WOT RPM range (Refer to Specifications and Maintenance) when at full throttle with a normal boat load.
• Operation at 3/4 throttle setting or lower is recommended. Refrain from prolonged operation at WOT RPM.
• Change the engine oil and oil filter. Refer to Maintenance.
• Change the transmission oil and filter. Refer to Maintenance.
