Air Filter; Removal - Mercury MR504LB3 Manual

1. Allow the engine to cool.
2. Remove the pressure cap from the expansion tank and coolant reservoir.
3. Remove the fuel filter for access to the engine coolant drain plug. Refer to Water‑Separating Fuel Filter.
4. If the engine has the optional fuel cooler installed, move the fuel lines so they do not obstruct access to the engine coolant
drain plug.
e
d
5. Remove the engine coolant drain plug and drain the coolant into a suitable container. Allow the engine coolant system to
drain completely. Dispose of the coolant according to local laws.
6. Ensure that the coolant has drained completely.
7. If required, clean the closed‑cooling system. See your local Mercury Diesel authorized repair facility.
8. Install and tighten the engine coolant drain plug.
9. Install the water‑separating fuel filter. Refer to Water‑Separating Fuel Filter ‑ Replacing.
10. Fill the system with the specified coolant. Refer to Checking and Filling the Closed‑Cooling System.

Air Filter

Removal

1. Loosen the clamp and remove the oil separator vent hose.
90-8M0089579 MARCH 2014
eng
f
c
a
b
a
Port side of engine
a - Throttle cable bracket
b - 14‑pin electrical connector
c - Water‑separating fuel filter
d - Fuel cooler with fuel lines moved to provide access (if
equipped)
e - General location of engine coolant drain plug
f - Engine control module
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Section 5 - Maintenance
Port side of block with
water-separating fuel
filter removed for access
a - Engine coolant drain
plug
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