Transmission Fluid - MerCruiser 305 CID (5.0L) Service Manual

SERVICE MANUAL NUMBER 24

Transmission Fluid

NOTE: Due to the various installation angles and oil cooler set-ups, it may be necessary to
adjust oil level.
Do not remove dipstick with engine running. Hot oil can cause burns.
Clean around the area of the dipstick before removing. Small particles of dirt can
cause damage to internal components and cause valves to stick.
IMPORTANT: DO NOT allow fluid level to drop below the bottom line.
TRANSMISSION WARM
The transmission should be at operating temperature (190° maximum) to get an accurate
oil level reading. Oil will expand when heated. Oil will drain back from the cooler. Expansion
and drain-back can significantly affect oil level.
1. When the transmission is at operating temperature, place selector lever in neutral.
2. Shut off engine.
3. Carefully remove dipstick and wipe clean.
4. Immediately insert clean dipstick and read oil level.
NOTE: Oil level must be checked immediately after engine shut-down to prevent an incor-
rect reading. Oil drains back into the transmission from the cooler and cooler lines.
5. Add or remove oil as necessary until the oil is at the required mark.
TRANSMISSION COLD
NOTE: For ease of checking the oil prior to engine start-up, a cold oil level mark can be
made. To find the cold oil level mark, the oil level must first be set according to the warm oil
level checking procedure.
1. Let the boat sit overnight. Insert clean dipstick and read level.
2. Put a mark on the dipstick at the cold oil level.
NOTE: You can use the new mark to check the oil level when cold. If oil level adjustment
is needed, add oil to the new mark. This procedure can be performed by the builder, dealer
or owner to ease fluid checking procedure.
Index
90-861327--1 OCTOBER 1999
WARNING
CAUTION
MAINTENANCE
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