Mercury MerCruiser Axius 350 MAG, User Manual, Page: 105 / 151

Section 5 - Maintenance
90-864197084 NOVEMBER 2008 Page 97
2.
a - PCV valve
b - Hose
3. If inspecting the valve with the engine stopped:
a. Disconnect the PCV valve from the hose.
b. Shake the PCV valve. If you hear a metallic rattle, the valve is functional. If you do not hear the rattle, replace the valve.
c. Install the valve onto the hose.
4. If inspecting the valve with the engine running:
a. Leave the hose connected to the PCV valve.
b. Start the engine. You may hear the sound of suction through the PCV valve.
c. Place a small sheet of card stock or heavy paper near the open end of the PCV valve. If the valve is working, the manifold
vacuum will suck the paper against the open end of the valve.
d. Stop the engine. If the paper was not drawn onto the open end of the valve, check the hose connection and for vacuum
leaks in the hose. If no leaks are present, replace the PCV valve.
5. Install the PCV valve in the valve cover and reconnect the hose, if not connected already.
6. Ensure that the PCV valve is tightly seated in the valve cover.
Replacement
IMPORTANT: Use only Mercury MerCruiser replacement parts to ensure compliance with emission regulations.
1. Remove the PCV valve from the port valve cover.
a - PCV valve
b - Hose
2. Disconnect the PCV valve from the hose and discard the valve.
3. Install a new PCV valve in the valve cover and reconnect the hose.
4. Ensure that the PCV valve is tightly seated in the valve cover.
mc71925-1
a
b
mc71925-1
a
b