Need to change oil in my Mercury 40hp 4stroke motor

[FishNotWork]

I got a 2006 40hp Mercury 4stroke engine - need to do an oil change. The previous owner had written down Mobil 1 10W30 for me - is this a good choice?!

I've heard that you can run Rotella T diesel motor oil in outboard engines - I've used that oil with my diesels and I know they are very reputable - can I run it in this Mercury marine engine?!

Thanks,
James

 

[Chris1956]

Re: Need to change oil in my Mercury 40hp 4stroke motor

Four cycle outboards have their own oil certification. Look for a FC-W motor oil. That stands for Four Cycle- watercooled. It is not as widespread as regular motor oil, but you should be able to find it. You can probably use Quicksilver 25W-40 oil as well. it should carry the designation, and it is used in MerCruiser engines.

 

[Jeep Man]

Re: Need to change oil in my Mercury 40hp 4stroke motor

I had asked my Merc technician about the proper oil for my engine (60 Bigfoot) just last week. His response was to only use Mercury oil. The additives are different than what is in automotive oil. He doesn't sell oil so he had no ulterior motive. You pay a little more, why take the chance.