OK, I am frustrated. Why is it that you cannot use what the OEM recommended? Is it cost? Is it genital size? Is it some version of "they don't want you to know"?
Just wondering?
Pull up any hatches and see if the fuel level sender is there. Look for a tag on the tank. If that doesn't get it, you may need to look under the console.
Alternatively, drain it into Jerry cans. Figure it to be about 40Gal.
Scott, Is your engine made by Michigan Motors?
Now my knowledge is dated, but my MerCruiser called for SAE-30 or SAE-40 or the Quicksilver 25W-40. I have seen newer four cycle marine motors that specified an FC-W oil, but never diesel motor oil.
Run what you want, but please update us on the...
Sure, just like those 60's cars needed to clear a flooded engine. Use the screwdriver to prop the choke open. Set the throttle to full in neutral.
Crank it until she fires, and then pull back on the throttle quickly to stop her from high RPM.
As was said. 2 cycle oil mixes very well with gasoline, especially in a portable tank. The 2 cycle OB OEMs recommend you put 1 gal of gasoline into a portable tank and then add the oil. Now shake the tank to mix it. Now fill the tank.
Automotive multivis oil is not recommended for sterndrive or OB boats. It does not have the warm viscosity to protect the engine under the high loads of water cooled, 4 cycle, marine engines. I do not know if the diesel oils protect or not.
Now I have never run auto oil in my sterndrive, and...
Gee, I have had no issue with my carbs in the last 20 years. I think it is because the e10 keeps the carbs and fuel system clean. I run a stabilizer in the fall and leave the carbs full over the winter. In the spring, she starts right up and runs perfectly.
Gee, what kind of oil is specified for your motor? I will bet it is FC-W oil. FC-W oil is specifically designed for sterndrive and 4 cycle OB motors. Why not use that?
