Engine Oil - Mercury MerCruiser Service Manual

IMPORTANT: If you use gasoline that contains or might contain methanol or ethanol, you must increase the frequency of
inspection for leaks and abnormalities.
IMPORTANT: When operating a Mercury Marine engine on gasoline containing methanol or ethanol, do not store the gasoline
in the fuel tank for long periods. Cars normally consume these blended fuels before they can absorb enough moisture to cause
trouble; boats often sit idle long enough for phase separation to take place. Internal corrosion may occur during storage if
alcohol has washed protective oil films from internal components.

Engine Oil

For optimum engine performance and maximum protection, use the following oil:
Application
All MerCruiser engines
IMPORTANT: Lubrication requirements for catalyzed engines differ from the requirements for noncatalyzed engines. Some
marine‑grade lubricants contain high levels of phosphorus. Although these high‑phosphorus lubricants may allow acceptable
engine performance, exposure over time will damage the catalyst. Catalysts damaged by lubricants containing high levels of
phosphorus may not be covered by the MerCruiser Limited Warranty.
If Mercury/Quicksilver 25W‑40 Synthetic Blend Engine Oil is unavailable, use the following lubricants, listed in order of
recommendation.
1. Mercury/Quicksilver 25W‑40 Mineral NMMA FC‑W Catalyst Compatible.
IMPORTANT: If you are servicing a catalyst engine, use the following oils for short periods of time only.
2. Other recognized brands of NMMA FC‑W Catalyst Compatible rated 4‑cycle oil.
3. Other recognized brands of NMMA FC‑W rated 4‑cycle oils.
4. A good‑grade, straight‑weight detergent automotive oil according to the last row of the operating chart below.
NOTE: We do not recommend nondetergent oils, multi‑viscosity oils (other than as specified), non‑FC‑W rated synthetic oils,
low‑quality oils, or oils that contain solid additives.
Use the following information for selecting the type of oil according to the order of preference.
90-8M0099748 eng DECEMBER 2015
Recommended Oil
Mercury/Quicksilver 25W‑40 Synthetic Blend Engine Oil, NMMA FC‑W Catalyst Compatible rated
Mercury/Quicksilver 25W-40 Synthetic Blend, NMMA FC-W Catalyst Compatible rated 4-cycle oil
Mercury/Quicksilver 25W-40 Mineral NMMA FC-W Catalyst Compatible rated 4-cycle oil
Other recognized brands of NMMA FC-W Catalyst Compatible rated 4-cycle oil
Other recognized brands of NMMA FC-W rated 4-cycle oil
SAE 20W
0° C
(32° F)
SAE30W
10° C
(50° F)
AIR TEMPERATURE
© 2016 Mercury Marine
General Information
SAE40W
53574
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