4 stroke engine oil

[Steven]

My Ymaha service manual says to use 10w-30 or 10w-40 oil that meets API: SE, SF, SG , SH or SJ

I looked on my quart of Yamalube and it is API SJ. I looked on a quart of Castrol Automotive oil and it meets(actually it exceeds) API SJ. I can't see any reason not to use the Castrol. My father said he was told by a Honda rep that they are now adding some new additive to Marine 4 stroke oils to combat some issue that is specific to marine engines. May have something to do with the orientation of the power head, my dad couldn't remember. Input to this topic welcome.

Steven

[Pro Wader]

I run Mobile1 synthetic and have never had an issue. (Cars, boats, 4 wheelers, lawn mower, generators...) My Suburban has over 220K and 200+ hours on a Honda outboard.
Because synthetic oil burns at such high temperatures, there is no coking and the engine oil pH is stabilized, which prevents internal corrosion.

That is just my opinion. I'm sure some will disagree but if it meets the specs, there should be no issues.

[Steven]

I've been doing some research on this. My father runs a pair of Hondas and was told by a Honda Rep not to run Synthetic until the engines have 500 hrs. on them. Said they're not fully broke in til then. From what I've read the primary problem is oil dilution and you have to have oils that have the proper additives to combat the problem. Auto oils that have API SJ have the necessary additives. Future auto blends won't. So it's ok to run auto oils now with SJ ratings, which is what the Yamaha service manual recommends.

[wadestep]

I've been brand loyal to Amsoil now for about 150,000 miles on cars, but not so much on outboards. They do make a 10-30 and 10-40 for marine engines. The reason I use synthetics is because of extended drain intervals, which I don't do on boats.

I've read the debate about using conventional oil for the break-in and somewhat longer. I personally believe that 500 hours of operation to break in a motor is very excessive. I don't think I'd support more that 100 hours, for me personally. I'd service it at 20 hours, and at 100 hours and then be synthetic from there forward.

However, there really isn't that much real, hard facts for this topic. The above is just my personal opinion.

Also - I change oil in my cars/trucks only 1x/year. That's between 8,000 and 17,000 miles. I have it tested by Blackstone Labs and it always comes back fine (including TBN). However, in the boat I always change at the 100 hour mark for normal operation because of the increase chance (in my mind at least) of contaminates and the increased duty cycle of marine engines. Since I'm not getting the benefit of the extended longevity of the premium oils, I often don't want to pay for them. I end up using synthetic outboard oil some of the time, but still throw it away at 100 hours.

Just my opinion. This is another one of those Ford vs Chevy topics.

[nc_robbie]

My Suzuki dealer told me to use mobile 1 “that’s what I personally use from day one” so I don’t know about the break in data but on my 3ed change I went to mobile 1, easier to find and a little cheaper. If you’re a costco member they often have a coupon for mobile 1….

[Steven]

I've read the debate about using conventional oil for the break-in and somewhat longer. I personally believe that 500 hours of operation to break in a motor is very excessive. This is another one of those Ford vs Chevy topics.

He wasn't really suggesting anything special for break in, just that he didn't recommend synthetic until 500 hours. Probably his own opinion. I haven't looked into Honda's official stance on it because I don't own one.

It is definitely a muddy area. On one side there are those who blindly use the manufacturers brand for either fear of warranty repurcussions, or out of a belief the oil is much better. They seem to discount the fact that the manufacturers profit from their oil. On the other side is the run any oil you want camp. I don't mind spending the money on the marine brands if I'm getting a superior product. From all my research, there is zero evidence this is the case, outside of what you find in the manufactures sales literature. From what I can find, if it is API SJ, it contains the necessary additives to prevent the issues dilution can cause. Soon auto oils own't comply to that any more, and you can bet the marine oil prices will jump considerably.

[whosmatt]

My Ymaha service manual says to use 10w-30 or 10w-40 oil that meets API: SE, SF, SG , SH or SJ

I looked on my quart of Yamalube and it is API SJ. I looked on a quart of Castrol Automotive oil and it meets(actually it exceeds) API SJ. I can't see any reason not to use the Castrol. My father said he was told by a Honda rep that they are now adding some new additive to Marine 4 stroke oils to combat some issue that is specific to marine engines. May have something to do with the orientation of the power head, my dad couldn't remember. Input to this topic welcome.

Steven

When in doubt, stick to what the owner's manual says. There is a NMMA spec for marine four stroke motor oil called FC-W but if your manual just specifies SJ (I think the current automotive standard is SN) then anything that meets that spec should be fine, SN included. If you want to really immerse yourself in motor oil debates, hop over to bobistheoilguy.com; they have some spirited discussions about oil.

[LOW277]

I work for a powersport manufacturing company and we also build engines. The crankcase oil that is in the engines when they are shipped from our factory is low bidder for a specific specification. We specify color, weight and a industry standard. We can use oil from multiple manufactures in the same model year.


All that said I use yamalube in my Yamaha outboard as the cost difference is minimal.

[tobolamr]

Hmmm would that be Polaris? Judging from your location... I'm just making a wild guess.

[Steven]

I just went with a marine oil that met the FC-W cert. I don't think I'm getting anything more for the extra money, which irritates me, but it's a small amount to worry over. I just dislike being sold something that I don't believe meets the claims.