Changing Fluids - Mercury 540 Bravo Manual

6. With the engine running, check the hose connections, fittings, and
gaskets for leaks. Also observe the engine temperature gauge to ensure
that the engine operating temperature is normal. If the gauge indicates
excessive temperature, stop the engine immediately and determine the
cause.
A sudden loss of pressure can cause hot coolant to boil and discharge
violently resulting in serious injury from burns. Allow the engine to cool
down before removing the coolant pressure cap.
7. After the engine has cooled completely, recheck the coolant level and add
coolant, if necessary.
8. If the reservoir was completely emptied of coolant, a significant amount of
air remains in the cooling system. Refill the reservoir to the "FULL" mark,
repeat the warm‑up/cool‑down cycle, and check the coolant level again.
9. Maintain the coolant level in the reservoir at or near the "FULL" mark with
the engine cold.
DRAINING
Contact your authorized Mercury MerCruiser dealer.
CLEANING
Contact your authorized Mercury MerCruiser dealer.

Changing Fluids

See the Maintenance Chart for the lubricant change frequency. The lubricant
should be changed before placing the boat in storage.
Power trim and power steering fluids do not require changing.
CRANKCASE OIL AND FILTER (BOAT IN THE WATER)
IMPORTANT: When changing the oil, make sure that the engine is near
operating temperature. Use only the recommended motor oil (refer to
Specifications).
1. With the engine off but at normal operating temperature, remove the
dipstick.
2. Install the crankcase oil pump onto the dipstick tube.
3. Insert the hose end of the crankcase oil pump into an appropriate
container and, using the pump handle, pump until the crankcase is empty.
a
eng
MAINTENANCE
CAUTION
!
b
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a - Crankcase oil pump
b - Crankcase oil pump hose