Marine Engine Oil

fish brain

Crew Member
How does marine engine oil differ from regular oil?
Do I need to use it in my motor?
 
I've been using Castrol/Quaker State in my outboards for 15 years.
There was a post many years ago where the oil was graded
marine vs automotive and virtually no difference.
 
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I‘m sure marine oils do in fact contain extra additives mostly do to maintaining viscosities longer in high RPM situations seen in outboards. But are they necessary. If your under warranty I would say yes for sure. After that if you change it regularly I highly doubt it makes much of a difference. But its a peace of mind type thing. There are many places in the real world where marine oil is not easily obtainable and their engines run just fine for many years.
 
I use Royal Purple 15w-40 in my little diesel and Volvo-Penta filters. The oil is what was recommended by mechanic at Gartland Marine. I can get cheaper oil and filters for sure but for piece of mine it's not a big deal in the scheme of things. Oil changes every 200hrs and still going strong with 2800hrs on the clock. Knock on wood.
 
How would you find which automotive filter would cross to your outboard? Trial and error?
Lots of info on the hull truth website. Lots of guys have them cross referenced to Wix filters. We can’t get those up here (at least at lordco we can’t, but we do have access to Baldwin filters which are phenomenal quality filters. Lordco can cross reference any wix number or other automotive filter you come up with.
 
Lots of info on the hull truth website. Lots of guys have them cross referenced to Wix filters. We can’t get those up here (at least at lordco we can’t, but we do have access to Baldwin filters which are phenomenal quality filters. Lordco can cross reference any wix number or other automotive filter you come up with.
There is an automotive place in qualicum that sells Wix filters. My friend use to buy his Yamaha 225 filters off of them. Can not remember the name of the business.
 
Lots of info on the hull truth website. Lots of guys have them cross referenced to Wix filters. We can’t get those up here (at least at lordco we can’t, but we do have access to Baldwin filters which are phenomenal quality filters. Lordco can cross reference any wix number or other automotive filter you come up with.
Napa Gold filters are a Wix filter. I have run them on every boat I have owned for both oil and fuel.

Most filters are fairly easy to cross on their website.

 
Lots of info on the hull truth website. Lots of guys have them cross referenced to Wix filters. We can’t get those up here (at least at lordco we can’t, but we do have access to Baldwin filters which are phenomenal quality filters. Lordco can cross reference any wix number or other automotive filter you come up with.
Shawnigan Mill Bay Auto Parts carries WIX filters. My Mercury 35-877761K01 filter is a WIX 10069 filter
 
I shouldn’t have said we can’t get them up here, although I did mention I only shop at lordco and they don’t carry them. I run Baldwin filters on all my stuff, they are about the best you can get for most automotive, if you can find a Donaldson filter for your application they are the top top of the line.
 
How does marine engine oil differ from regular oil?
Do I need to use it in my motor?
This post and all the comments was the inspiration I needed to send my Mercury semisynthetic 25W40 out for analysis!

For this test I bought another brand of 25W40 that carries the same FC-W certification as a test comparison and actually to my extreme dismay…….

The Mercury Marine Oil had double the additives the other Oil did and some stuff that was Zeros on the form. My analyst was also surprised and actually thought I had an antifreeze leak until he remembered it was for an outboard. This was because of the 210ppm of Boron which until 2008 has only been an additive usually found in some coolants.
Google this and you will find Boron is magic in oil! There was Zero ppm in the brand X. There was also 881ppm of zinc, 58ppm of Molybdenum and 2340ppm of calcium which not only cleans but is also an anti-wear additive.

The funny but cheeky comments about your crankcase not living in seawater isn’t totally true because I guarantee you if you sampled your oil at the end of the season you would find sodium on the oil analysis (minute amounts but it’ll be there) and it’s from the air your outboard engine breaths!
All the additives listed above adheres to the surfaces of metals and helps fight that corrosion. Outboards suffer from sitting in the off season as we know.

I was really and truly hoping that it was all propaganda and industrial lies covered in fancy labeling but I will keep buying Marine oil. Specifically Merc’s stuff.
And, in all honesty it’s really not that much more expensive than semisynthetic car oils is it?
 
Its not really about cost for me but I do buy my full synthetic Castrol for about $7 per liter on sale.
Yamalube semi-synthetic is around $25.
Performance is really all that matters and like I said previously 1300 hours and going strong.
Pretty good video earlier on comparing Honda and Pensoil.
 
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