I recently bought a 2000 fountain sportfish/ walk around cabin. It has twin 225 merc efi
99 year.
The oil light on the dash comes on after running for a few minutes.
Both oil tanks are full. I'm not getting an alarm just a light on for the port engine. Is the light from the main tank in the Hull or tank on engine?
thanks

Most likely the tank on the engine. It needs to be completely full. Just crack the cap with the engine running and it will fill itself from the large tank.

I missed the part where you said both were full. Mine will come on if the level drops an inch from the top. I never have an issue with my oil tanks staying full unless I store it with the engines raised, then they tend to drop the oil level a little.

OK. The tank was full when I checked and ran the engine. I'll check it again. Thanks

Now that I think, the engines were up for about 3 weeks before I ran it so tank might have filled before I got cowl off.
thanks again