Engine Oil; Checking And Filling The Engine Oil - Mercury MerCruiser Service Manual

Maintenance
Task Interval
Every 5 years

Engine Oil

Checking and Filling the Engine Oil

Discharge of oil, coolant, or other engine/drive fluids into the environment is restricted by law. Use caution not to spill oil,
coolant, or other fluids into the environment when using or servicing your boat. Be aware of the local restrictions governing
the disposal or recycling of waste, and contain and dispose of fluids as required.
Oil Level—Overfilled
An overfilled crankcase—oil level too high, can cause a fluctuation or drop in oil pressure, and rocker arm clatter. This condition
results in the engine crankshaft splashing and agitating the oil, causing it to foam—become aerated. The aerated oil causes the
hydraulic valve lifters to bleed down. This, in turn, results in rocker arm clatter and loss of engine performance, due to the
valves not opening properly.
Care must be taken when checking the engine oil level. The oil level must be maintained between the minimum and maximum
marks on the dipstick. To avoid getting a false reading, adhere to the following procedures.
Checking
1. Stop the engine. Allow approximately five minutes for the oil to drain into the oil pan. The boat must be at rest in the water.
2. Remove the dipstick. Wipe the oil from the dipstick.
NOTE: Ensure that the dipstick is installed with oil level indication marks facing the rear of the engine—flywheel end.
3. Install the dipstick fully into the dipstick tube. Wait one minute to allow trapped air to vent.
Page 1C-8
• Replace the coolant/anitifreeze. Replace every two years if not using extended‑life coolant/
antifreeze.
In-line drive model shown
© 2016 Mercury Marine
Maintenance to Be Performed
NOTICE
58400
58402
90-8M0099748 eng DECEMBER 2015