Mercury 300R HD CMS Mechanical Operation And Maintenance Manual page 36

4. Remove the dipstick and observe the area of the five beads.
a
a - Service access door
b - Oil fill cap
c - Dipstick
5. The bead or crosshatch which shows oil furthest from the end is the oil
level.
NOTE: New oil (level) may be difficult to identify which is why the crosshatch
between the beads are part of the dipstick assembly. When checking the oil
level, if oil is on any of the five oil range beads or four crosshatch, the oil level
is within the safe operating range. When the oil level is only on the lowest oil
range bead, the operator can add 1.8 Liter (2 US qt) of oil and the level will
remain within the safe operating range. When the oil becomes dark from hours
of product use, it will be easier to identify the oil level on the dipstick.
FUEL AND OIL
b
c
Oil level example
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