Got caught my first time!

I would consider the National Marine Manufacturers Association (NMMA), a long standing and well respected organization, to be the authority on the needs of marine engines. I would be inclined to trust their recommendations over Internet opinions. The NMMA states the following in their Certification Procedure Manual for FC-W® and FC-W Catalyst Compatible® Four-Stroke Cycle, Water-Cooled Gasoline Engine Lubricants:

"Recently introduced, larger 4 and 6 cylinder four-stroke cycle outboard engines are now taking the place of some conventional two-stroke cycle outboard engines. The duty cycles of marine engines have always discriminated these engines from over-the-road light and heavy duty automotive engines. In particular, the lubrication demands of marine engines are unique. High loads, high speeds, and exposure to high levels of humidity and salt water are just a few of the unique characteristics of an engine in the marine environment. Aware of the particular lubrication requirements of four-stroke cycle engines in the marine market and their increasing use, the National Marine Manufacturers Association Oil Certification Committee developed the four-stroke cycle engine oil specification, NMMA FC-W®."


Clearly the industry technical authority on four-stroke marine engines believes the lubrication demands of these engines are unique and different from that of light and heavy duty automotive engines, and accordingly have developed a set of tests and specifications specific to the needs of marine four-stroke engines. That's good enough for me, even without knowing the details of how the marine formulations are different. Therefore I would place my trust in the NMMA and look for certification against FC-W.
 
I hear your logic, Tom. But there are some conflicts of interest that make me hesitate to take their words at face value. NNMA members include the manufacturers who make the oil, these manufacturers pay NNMA the fees to get the cert, and both of them push the oil. None of the FC-W oils seem to have product specs available online, which is out-of-norm from the rest of the oil industry. If none of the makers have been able to quantify or specify to the public what makes their oils different and better, it's possible there isn't anything. Ads like this which throw out tons of catch words and slick advertising, while providing zero hard info on their product in six and a half minutes, don't help their cause for the skeptic:

Again, if anyone has technical information on differences between marine and diesel oils in makeup, base oils, additives, corrosion inhibitors, etc, I'm all ears.
 
Thanks Drew. I mainly operate in saltwater, so corrosion is always a concern. The oil I'm looking at has strong corrosion protection, I think. No one has said otherwise here at least.
So just because no one here has said anything to the contrary do you think that’s true?

But I guess that’s the problem when relying on unsubstantiated information you think you hear on the Internet rather than real-world proven results from approvals and standards.
 
Again, if anyone has technical information on differences between marine and diesel oils in makeup, base oils, additives, corrosion inhibitors, etc, I'm all ears.
Yes, the details of FC-W which is exactly what you asked for and was provided to you. What is it that you’re looking for now? More testimonials from Internet discussion boards?

At some point you realize this is no longer a technical discussion that involves facts.
 
So just because no one here has said anything to the contrary do you think that’s true?

But I guess that’s the problem when relying on unsubstantiated information you think you hear on the Internet rather than real-world proven results from approvals and standards.
Dude, you’re a troll, go away. Or are you on NNMA or Yamaha payroll and it’s your job to obfuscate the issue?
 
At some point you realize this is no longer a technical discussion that involves facts.
You haven’t contributed anything to a technical discussion. You’ve pointed to a cert a bunch of times, with no info for why it’s good. And you haven’t directly answered the questions I and others have asked you. Here’s one more for you to try: how is the FC-W corrosion test better than the ones done for diesel certs?
 
BIL's 20+ boat has a big yamaha OB>I'm gonna find out what he uses for oil and why. You guys keep the topic open and I'll get back to you with anecdotal info to further obfuscate the issue🍿:cool:
 
You haven’t contributed anything to a technical discussion. You’ve pointed to a cert a bunch of times, with no info for why it’s good. And you haven’t directly answered the questions I and others have asked you. Here’s one more for you to try: how is the FC-W corrosion test better than the ones done for diesel certs?
Which corrosion test is that for which diesel cert?
 
Dude, you’re a troll, go away. Or are you on NNMA or Yamaha payroll and it’s your job to obfuscate the issue?
You had a technical and detailed response from TomNJ (who by the way knows what he’s talking about, do you know who he is?) yet you continue to post nonsense questions about fictitious diesel certifications that clearly you know nothing about. How does that make me the troll? Every question or comment I have made in this thread has been relevant to the subject. It is you that will not listen nor engage in substantive dialogue. You were given exactly what you asked for.
 
You had a technical and detailed response from TomNJ (who by the way knows what he’s talking about, do you know who he is?) yet you continue to post nonsense questions about fictitious diesel certifications that clearly you know nothing about. How does that make me the troll?
I appreciated Tom’s response, but a bunch of it was a copy-paste from NNMA’s website. And it appears it could be a case of the fox guarding the hen house, although I believe the test is good. If diesel certs don’t have a corrosion test, that’s the first piece of knowledge I’ve learned from any of your posts. You keep banging on the table saying the cert is good, trust the cert, and I’m trying to understand why I should trust it and how marine oils are formulated differently than good diesels. You either can’t or won’t answer that. Other posters in this thread have said marine oil is rebranded diesel, and you haven’t denied that. As far as I can tell, there’s far more pedigree and history of quality with a Schaeffer diesel oil than marine oils which won’t even share the most basic of product information and have a relatively new cert. And you also brushed off the fact that Yamaha still says API oils are good to use. Diesels have more protective additives than API.

I assume you know a lot about oil by your post count, but you don’t seem willing to share that knowledge or answer straightforward questions. I’ll probably stop responding to you since we seem to be talking past each other and not getting anywhere. Thanks.
 
I hear your logic, Tom. But there are some conflicts of interest that make me hesitate to take their words at face value. NNMA members include the manufacturers who make the oil, these manufacturers pay NNMA the fees to get the cert, and both of them push the oil.

Specification and test development is a very expensive process and someone has to pay for it. In this industry that is the stakeholders, such as the engine builders, oil companies, additive companies, and consumers. It is a necessary and cooperative effort based on need and science rather than business bias. In the end everyone benefits - engines are protected better, oil formulators have solid targets to develop against, and consumers get better oils. Certification fees help offset some of the cost. The same process is used in the development of specifications for API automotive oils, jet engine oils, and others.

The very first step in the process is the establishment of need. No one wants to invest millions of dollars and years of time developing tests and specifications if there are no pressing needs for improvement in the field. The need step is highly debated by the technical committees and taken very seriously. The industry has determined that there is a need for different formulations for marine engines and invested in developing them.

Based on the statements from the NMMA it appears high loads, high speeds, and exposure to high levels of humidity and salt water were among the factors dictating the need for a new specification for marine engines. Knowing and having participated in such a process I feel confident that such needs were addressed in the final specification. Trust me the industry does not do this for fun and profit.

You should not assume there is no benefit from these formulations just because the marketers do not list their data. Some companies choose not to play the paper sale approach by throwing out test results to consumers who do not understand them, and prefer to use marketing language instead. Yes that may be frustrating to technical types but it does not mean there is not some technical meat behind the products.

I believe you may be over thinking this. FC-W oils were designed specifically for marine engines by an industry that determined there was a need to do so. Other oils may work to a degree and even be adequate for some engines and operating environments, but knowing how the development process works and the technical competence and seriousness of the participants, I would certainly choose an oil specifically designed for the application and certified against the specifications.
 
Thanks for your response, Sir! You answered many of my questions and concerns and led me to more strongly consider sticking to FC-W oils. I’m still interested in any insights people have into why this cert was required and the composition differences, if any, between marine and diesel oils.
 
And I agree, I’m sure I’m overthinking this. But isn’t that the whole point of BITOG, people overthinking oils? 😆
 
Hi BITOG’ers, thanks for this site and all the knowledge you’ve shared. You can skip this paragraph and the next two if you just want to get to the oil recommendations part. I came across this site while researching what oil to put in my boat engine, and went way down the rabbit hole reading a ton and losing a bunch of sleep on here over the last week (yes I’m an engineer, ha). Now I know way more than I ever thought I would about oil, although my brain can only assimilate so much knowledge in a week and I’ve just scratched the surface.

Based on what I’ve read, I went to buy some non-manufacturer recommended oils today for my cars. I made the mistake of answering what vehicle I was getting oil for when the oil stocker asked. I had to listen to him go on about how cars in Europe are made differently, engineers know what spec is best (as if engineers ever get to make the final call on business decisions), etc. I got a blank stare when I tried telling him about different additive packs, how viscosity changes with temp, etc. He did agree that it probably wasn’t in an automotive company’s best interests for your vehicles to last a long time. I waited until he started talking to another customer, then grabbed the oils I wanted and hightailed it out of there. It’s funny, it felt sneaking a cookie out of the cookie jar or stealing something.

My wife is also skeptical of doing something different than what the manufacturers say, and isn’t on board with me changing her Toyota Sienna’s oil yet. So I’m hoping I can get some validation from you all on what I selected, or some correction if I’m off the mark. Here’s my plan for vehicles and boat.

Overall objectives: Minimize wear on my vehicles for maximum life, while also balancing oil and gas costs
Location: Washington state


Vehicle: 2012 Ford Expedition
- Mileage: ~200K
- Use: Hardest usage is as a tow vehicle for a 4k or 5k pound boat and trailer. I also try to drive it once a week when it’s not boating season. It only sees a few thousand miles per year, but works hard towing a boat over passes.
- Oil: 0w40 Mobile 1 FS. I thought the Mobil 1 would hold up well in a towing environment, but hopefully not decrease gas mileage or power noticeably since it’s a pretty light 40 weight.


Vehicle: 2007 Ford Freestyle
- Mileage: ~125K
- Use: Daily commuter, get 6 to 8K miles a year
- Oil: I wanted to get Quaker State 5w30 UD, but they only had 5w40 UD or 10w30 UD. I grabbed the 5w40, but may return it and go to another location that has 5w30 UD.

Boat motor: 2009 Yamaha F150
- Useage: Typically low hours, ~50 or so a season. Boat mostly cruises at ~4500 rpm, as well as some time at 5900 rpm to blow things out, and some low sped trolling. - The boat is heavy and the motor is pretty loaded. It sometimes sits for several months in the winter without being run
- Oil: Schaeffer’s 5w40 OTR plus. Specs on this look similar to Rotella T6 which many use successfully in outboards. Schaeffer oil seems to have a rep for being high quality and holding up very well. Plus their moly cocktail sounds really cool. I like the idea of a protective layer being built up to prevent corrosion and protect against wear when the boat is fired up cold after sitting for a while. I'm not sure if their moly works as advertised or if it's just a good sales pitch. This oil may be overkill due to the low number of hours it sees, but I’m more concerned about preventing any corrosion or other buildup in it, as well as avoiding wear when it’s started.

As an aside, I looked at the marine rated FW-C oils, and those jokers share basically nothing about their oils. It’s pretty much a jedi mind trick they’re pulling: “trust us, this oil is what your engine needs.” Unless they decide to be more transparent or I see more VOAs/UOAs on them, I’m not going to risk paying a premium for what may be crappy, cheap oil.

The oils I picked seem to have strong additive packs (moly, ZDDP, etc.), decent HTHS and TBN levels, are known performers with good reputations, and are relatively inexpensive. Please let me know if you think these are decent picks, or if I should be listening to my wife and the oil jockey to stick with manufacturer specs. Do I need to worry about oil film thickness or strength on any of these, especially the boat which may sit for months? Thanks in advance!

From my experience, boat engines spend a lot more time under load and at high RPMs, as compared to car engines. And I doubt you will operate it below freezing temperatures much. With this in mind:
2012 Ford Expedition - M1 0W40 (lower spectrum of 40), or Castrol Edge 0W40 (higher end of 40), or QSUD 5W40 Euro (smooth juice).
2007 Ford Freestyle - QSUD 5W30 is perfectly fine, but you could definitely simplify the oil stash by running the same oil as in Expedition.
Sienna - same as Fords.
2009 Yamaha F150 - Mobil1 15W50, to help battle oil shear due to high and constant RPMs under load. Or NAPA 15w50.
 
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And I agree, I’m sure I’m overthinking this. But isn’t that the whole point of BITOG, people overthinking oils? 😆

Here is what someone else said about BITOG, and I tend to agree.

98% of what is discussed on BITOG is purely mental masturbation with no real world importance other than feeding the OCD needs of the group to obsess over things that do not matter.
 
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I don't get the humidity aspect. For every gallon of gasoline your engine consumes, about a gallon of water is produced.
In other words, it's raining inside the combustion chamber and the water is going out of the exhaust.

Edit; What happens when you drive your car on a hot humid day?
 
As far as four cycle, water cooled boat engine oil (FC-W), There is an SAE paper #2007-32-0079 written by Brent Dohner of Lubrizol Corp. that explains the reasons and methods for developing this specific oil. The abstract mentions protecting against salt water corrosion, while operating at lower engine temperature with open loop cooling and extensive trolling, extra wear protection when quickly increasing load from idle to full throttle by maintaining higher High temperature high shear viscosity (HTHS) and extra corrosion protection during long seasonal storage. These oils seem to have a considerably different additive package than automotive oils and I would follow the boat engine manufacturer's recommendation.
 
As far as four cycle, water cooled boat engine oil (FC-W), There is an SAE paper #2007-32-0079 written by Brent Dohner of Lubrizol Corp. that explains the reasons and methods for developing this specific oil. The abstract mentions protecting against salt water corrosion, while operating at lower engine temperature with open loop cooling and extensive trolling, extra wear protection when quickly increasing load from idle to full throttle by maintaining higher High temperature high shear viscosity (HTHS) and extra corrosion protection during long seasonal storage. These oils seem to have a considerably different additive package than automotive oils and I would follow the boat engine manufacturer's recommendation.
www.lubrizol.com look under recreation

Maybe we can find the additive package on their web site.

A few others...

www.oronite.com
www.api.org
www.infineum.com
www.aftonchemical.com
www.vanderbiltchemicals.com
 
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Thanks guys, I read that paper’s abstract and will check out those links later. The abstract talked about high ZDDP being good to protect boat engines, but bad on car catalytic converters. Like I mentioned earlier, Yamaha still says it is acceptable to use API oils in the engine. If API is OK, wouldn’t a diesel be better with its higher HTHS and more anti-corrosion additives and detergents? If I read old threads correctly, CAFE and LSPI concerns caused auto oils to change and be less suitable for boat engines, which drove the marine guys to do the FC-W label. But I still haven’t heard a reason other than “trust the manufacturer” for why a strong diesel is a bad choice for a marine application, or what the differences between a marine and diesel oil are.
 
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