10W-30 outboard oil recommendations?

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Nov 18, 2020
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The Netherlands
I am planning to change the oil in my Honda BF 50 this winter, Honda prescribes 10w30 oil.

In europe its hard to get official honda 10w30 outboard oil, its only sold in liter bottles and costs a fortune. It is not FC-W approved like the honda 10w30 marine oil is in the USA.

This engine needs 3.3 litres if i am not mistaken. So that would be 4 bottles times 16 euros =64 euros.

I also see quicksilver (mercury) mineral 10w30 is sold in 4 liter bottles for 40 euros.
Castrol outboard 10w30 for 10 a liter, no fc-w approval though.
Motul and liqui moly for aroud 45 euros for 5l.

Yamalube 4-Stroke Synthetic Marine Oil SAE 10W30 for 63 euros​

Quicksilver 10w30 syntetich blend 4l for 63 euros.

Besides from brand preference does anybody have any good reasons to choose one over another? Failure rate per brand? Who makes the oil for the oems?
I also heard outboard oil is never fully synthetic because syntetics are vulnerable for moisture.
 
My vote is for Yamalube synthetic! No reason other than I prefer synthetic oil for cold starts and high temp protection.

What is your time change interval? by hours or just yearly time or ???

Was under the impression that Honda is recommending 5w30's now too.

Are there any heavy duty 'diesel' engine trucker 10w30 oils, or automobile oils in your autopart stores?

I don't care for FC-W. So, I might consider other grades/oils too, like 5w30, 10w30, and 0w40's. But, if under warranty, follow the manual grade/type recommendations and keep records.

What filter are you using? Guessing it takes the ph6607 sized equivalent, common to many car engines.
 
I use OEM honda filter, eventhough i estimate to make more then 100hrs a year i change the oil only every winter.

I like to stick to fc-w approved marine oils.
5w30 is also approved but i see most marine oils are 10w30, because its a carburated motor and they tend to dilute the oil with fuel when a lot of slow speed idling is done i like to stick to 10w30.
Outboars do not run that hot so the oil does not really vapourize the gasoline and moisture.
 
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Honestly. if you ran whatever brand of synthetic oil I'm sure that Honda will last forever... or any other brand of outboard. I've ran marine and non marine oil in my Merc 30hp. Hasn't blown up yet.....
 
The outboard oils put focus on anti foaming - think most HDEO’s pass those tests - but a dealer did twin engine WOT testing here - (basically a long run to an offshore platform) 5W30 “car lubes” foamed when approved marine lubes did not …
Not scientific - but aerated oil on the dipstick was only seen in 1 motor …
Many 4 strokes don’t hold much oil to start with …
 
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If you look at VOA's you'll see just as much silicon in pcmo as "outboard oil". But , outboard oils are pretty high in zinc.
 
The outboard oils put focus on anti foaming - think most HDEO’s pass those tests - but a dealer did twin engine WOT testing here - (basically a long run to an offshore platform) 5W30 “car lubes” foamed when approved marine lubes did not …
Not scientific - but aerated oil on the dipstick was only seen in 1 motor …
Many 4 strokes don’t hold much oil to start with …
Why would foaming be any more of an issue in an outboard than it is in any car, motorcycle, non-diesel ICE, etc? What about Honda's large outboards which are just repurposed auto engines? My Suzuki 175s have an 8 1/2 quart oil capacity each - that's " (not) much oil to start with"?This is from my Suzuki owner's manual:

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Note no FC-W requirement for the Suzukis. This is from the Yamaha F300 (6.66 quart oil capacity) owners manual, again no FC-W requirement, API certs are fine. In all likelihood much better oils are available with API certs than FC-W certs - think various Porsche and VW certs that are also (easily) API.

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Note no FC-W requirement for the Suzukis. This is from the Yamaha F300 (6.66 quart oil capacity) owners manual, again no FC-W requirement, API certs are fine. In all likelihood much better oils are available with API certs than FC-W certs - think various Porsche and VW certs that are also (easily) API.

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If you look at the OP - he’s asking about small/mid 4 strokes of which there are thousands- my F60 only holds 2.6 quarts
FC-W is from what many OEM’s assembled - and they bench test with F150’s … doubt they‘d want to use automotive derivatives because most outboards are not. All OEM label oils carry this approval … Mystik and others do as well …

I shared what a large/mature service department did on their own - tested a long run offshore at WOT … Visible air in oil might be OK for some - not others. Back to your first reply - who drives cars like that … ? Or has very humid air intake …
What you posted is that they “recommend” NMMA’s oils - doubt they can force you to do anything … but it’s similar to other warranty debates folks have here over how they interpreted the manual …
The automotive world is moving away from the viscosity spreads that outboard OEM’s continue to recommend (and test) in some motors - another reason a higher TBN HDEO is perhaps a better/proven alternative to save money on oil …
(but Noack should be compared) …
 
The Quicksilver FC-W is fine oil. I use (10W30) in my 200 horsepower 4 stroke. No foaming and as mentioned above, outboard motors always have fuel dilution. Some to the point of “making oil” when trolling for lengthy fishing outings etc. Why try and save a few bucks and not protect that huge investment hanging on the stern??
 
Havoline has a 10w30 outboard oil, vis @ 100C is 12.44

Probably harder to obtain in the Netherlands.

What about that?

 
If you look at the OP - he’s asking about small/mid 4 strokes of which there are thousands- my F60 only holds 2.6 quarts. No, he's talking specifically about a Honda BF 50. The oil capacity is 3.3 liters - that seems to me to be fair bit of oil for a water cooled motor that only puts out 50 hp. And certainly not consistent with your unsupported claim that "4 stokes don't hold much oil" (exactly what does that mean, anyway)? And what is the point you are attempting to make?
FC-W is from what many OEM’s assembled (exactly what does that mean?)- and they bench test with F150’s … doubt they‘d want to use automotive derivatives because most outboards are not. All OEM label oils carry this approval … Mystik and others do as well … I sincerely doubt that you know what Yamaha uses to bench test their 150s(or any other motors for that matter) and even if you miraculously did why do they continue to recommend non FC-W oils in their manuals if they're not appropriate?
Let's get really specific and to the point here with a fact for the OP as opposed to unsupported anecdotes. Copied directly from the Honda BF50 owner's manual:

Engine Oil Recommendations
Oil is a major factor affecting performance and service life. Use 4-stroke detergent oil.
SERVICING YOUR OUTBOARD MOTOR Spark Plug Service
SAE 5W-30 is recommended for general use.
Honda recommends that you use API service category SG, SH or SJ oil. The SAE oil viscosity and service category are in the API label on the oil container.


I shared what a large/mature service department did on their own - tested a long run offshore at WOT … Visible air in oil might be OK for some - not others. Back to your first reply - who drives cars like that … ? Or has very humid air intake … This is nothing but an unsubstantiated anecdote and a poor one, at that, although it is humorous. It is in all respects the equivalent of my local Dodge mechanic telling me that synthetic oil will ruin my Cummins because it is "too slippery" Again, I guess these "guys" (and you) must know better than the major manufacturers with respect to appropriate oil specs and clearly, according to you, their recommendation for automotive grade oils is inappropriate. For readers who find these n=1 anecdotes more compelling (or compelling at all) than the mfg specs, well, I guess they're you're audience and are, of course, free to do what they want.
What you posted is that they “recommend” NMMA’s oils - doubt they can force you to do anything … but it’s similar to other warranty debates folks have here over how they interpreted the manual (mmm, I never commented on warranties. Perhaps you're referring to another poster … I'm not sure what this has to do with this discussion - read the manufacturers' recommendations that I posted. No interpretation required, it's right there in black and white for everyone to read. Those are the facts of manufacturer's recommendations. Read the three excerpts from the Suzuki, Yamaha and Honda owner's manuals that I posted. I'm not sure why it's controversial for guys like you to run specs (any or all) recommended by manufacturers. I know, I know... you and the guys in your local service shop know better. The automotive world is moving away from the viscosity spreads that outboard OEM’s continue to recommend (and test) in some motors - another reason a higher TBN HDEO is perhaps a better/proven alternative to save money on oil …Not sure why we've now introduced a TBN discussion, but it's a red herring. A HDEO that meets the specs is no better than any other oil that meets the manufacturers specs. If you have proof that it is, by all means share it with us. Automotive oils that meet recommended viscosity recommendations are, and always have been, readily available.
(but Noack should be compared) …
See my responses in green text, above.
 
See my responses in green text, above.
That lots of green - but you clearly need to read more from the OEM which is part of NMMA along with formulators … and THEY test with outboard motors … and many other ASTM standards with extra tests for foaming and corrosion …

It is pretty simple that a large dealer ran a twin engine WOT - one on car oil and one on NMMA … One foamed … Simple



Run what you want … Adios (on ignore) …

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