View Full Version : Type of oil

03-23-2009, 09:43 PM
What type of oil does everyone use? Marine Grade, is there a difference? Yeah maybe I opened a can of worms.

03-23-2009, 10:17 PM
Oh, the can of worms has been opened again!!!

I use mobile 1 10w30 fully synthetic.

03-24-2009, 01:20 AM
Oil is the great debate. I just purchased my boat and plan to stick with the previous owners oil choice, Rotella 15W40. Marine oil not common where I'm at so regular is my choice. (Indmar recomends 15W40) I don't run synthetic because Indmar says not to unless you have over 100 hrs. My veiw on oil is;

Old oil is better than no oil.
Wrong oil is better than no oil.
Can't leak oil if there is no oil in it.

03-24-2009, 04:08 AM
marine oil can hold better when mixed with water, only difference when it says marine

03-29-2009, 03:35 PM
Indmar Does Push The Pennzoil Marine 15w40...same When I Had My Malibu...but I Hear Great Things About The Shell Rotella 15w40...rec For Diesel Engines...quality Oil...and They Sell It At Wal Mart......

03-30-2009, 08:47 PM
Royal Purple in my baby!!!

03-30-2009, 09:15 PM
Gawd i just love these oil threads but in a nutshell i've learned two things from 35 years of wrenching on all types of engines whether air cooled (my Harleys), auto or marine is this ... one, the proper oil could be the difference in longevity or put another way ... your marine engine lasting 1000 hours with issues or 2000+ without. Two, I've also learned that everyone is an oil expert on what is acceptable and what isn't so i no longer get sucked into the great oil debates. :p

And for what it's worth my oil of choice if anyone is interested is Mobile 1 for at least 25 years now in everything.

03-30-2009, 11:22 PM
Your engine owners manual states the required certifications that the oil should have. Buy an oil that meets at least those minimum and you will be fine.

03-30-2009, 11:52 PM
I recently changed oil to Royal Purple 15/40. My idle actually increased after the change (I had to adjust it back down), so I'm guessing that there was a definite decrease in friction.

03-31-2009, 11:10 AM
What I know from research on here and elsewhere: The Pennzoil marine is recommended, even pushed, and usually available at Wally's. After 100 hrs. you can go to synthetic. Everybody has their own opinions about which one of these is best. If you can't find the Pennzoil, the Rotella meets all the same specs.

04-25-2009, 06:45 PM
Wow, 15w40. I used to work in the marine service industry and we only used 30w. Boy, things have changed. (1990-1994)

Mid Tenn LSV
04-26-2009, 12:24 AM
Just put in 5 quarts of Delo today. Made the 30 mile treck to pick up Pennsoil at the marine store and they were out. They sold me the Delo instead. Think I will stick with it since the Delo is available and a bit cheaper at the auto parts store 3 miles from the house. I imagine that there are many who believe there are better choices, but I will perform frequent oil changes (with the help of my oil extractor) and spend my time worrying how to get on the water instead of how can I make it to the marine store during business hours.

04-28-2009, 09:07 PM
I ran Mercruiser 25-40w engine oil in 2 boats and over 1000 hours . No lubrication issues in either one , and now running it in my Indmar (chevy) v-8 with another 80 hours . Mercruiser oil is made to their specs as far as water issues and having it breakdown in viscosity , etc, there is nothing wrong with synthetic oils , I understand that they hold their viscosity better under high heat and loads. I run blended synthetics in my turbocharged high rpm drag racer and have yet to loose an engine due to lubrication issues. Oh, I am a mechanic with 30 plus years of experience , industrial and automotive. Usually what the manufacturer recommends is a good rule of thumb. My 2 cents. Jim.