I have a 4 stroke Yamaha F115 (actually a pair), they have around 600 hours on them. I have been running Yamaha 4 stroke oil 10w-30 but I want to switch to a fully synthetic. Not really an easy thing to do and get a Fc-w rated oil. I am probably going to go with Mobil 1 (I realize technically not fully syn). I change my oil sooner than required at usually 85 or 90 hours instead of the 100.. I dont think the Yamaha oil is that good of an oil..Thanks for any advice?
4 stroke outboard oil
- Thread starter lsd6988
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Amsoil WCT, no need to look further....especially with that kind of investment.
It looks like all I could find was sierra and amsoil in a 10-30.
Amsoil is the better oil , I am sure.
There were no FC-W oils back in 2004.
The FC-W standard was introduced by NMMA after the amount of anti-wear additives in automotive oils was reduced in 2006 in order to protect catalytic converters. The latest automotive standards are even more restrictive. FC-W oils have more in common with 2004 automotive oils than the oils that are designed for modern cars.
Most diesel oils would likely meet FC-W standards. But not modern automotive oils.
Because outboard motors have no catalytic converters additives can be used that can't be used in automobiles. So indeed the FW-C spec oil may have a better additive package or more additive than API spec oil for cars. BUT... outboard motors are different than car motors and could benefit from different or additional additives. Your typical car motor likely sees very little use over 3000 RPM. Most cars cruise down the highway at 60mph at less than 3000 RPM. Outboard motors can live a considerably larger portion of their life over 4000 and even 5000 RPM or higher.
Synthetics have hydrocarbons that are uniform and share similar sheer characteristics. Synthetics resist shear better than conventional oils for longer periods of time. In conventional oils some of the different size hydrocarbons break down earlier than others reducing the ability for the oil to protect the engine. Synthetics also vary in quality but that's for another topic. Just because a synthetic doesn't have a FW-C seal on it doesn't mean it does not meet the spec for FW-C oil. It likely far exceeds it.
Originally Posted By: lsd6988
I have a 4 stroke Yamaha F115 (actually a pair), they have around 600 hours on them. I have been running Yamaha 4 stroke oil 10w-30 but I want to switch to a fully synthetic. Not really an easy thing to do and get a Fc-w rated oil. I am probably going to go with Mobil 1 (I realize technically not fully syn). I change my oil sooner than required at usually 85 or 90 hours instead of the 100.. I dont think the Yamaha oil is that good of an oil..Thanks for any advice?
Originally Posted By: chad8
The FC-W standard was introduced by NMMA after the amount of anti-wear additives in automotive oils was reduced in 2006 in order to protect catalytic converters.
Most diesel oils would likely meet FC-W standards. But not modern automotive oils.
Because outboard motors have no catalytic converters additives can be used that can't be used in automobiles. So indeed the FW-C spec oil may have a better additive package or more additive than API spec oil for cars. BUT... outboard motors are different than car motors and could benefit from different or additional additives. Your typical car motor likely sees very little use over 3000 RPM. Most cars cruise down the highway at 60mph at less than 3000 RPM. Outboard motors can live a considerably larger portion of their life over 4000 and even 5000 RPM or higher.
Synthetics have hydrocarbons that are uniform and share similar sheer characteristics. Synthetics resist shear better than conventional oils for longer periods of time. In conventional oils some of the different size hydrocarbons break down earlier than others reducing the ability for the oil to protect the engine. Synthetics also vary in quality but that's for another topic. Just because a synthetic doesn't have a FW-C seal on it doesn't mean it does not meet the spec for FW-C oil. It likely far exceeds it.
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Not sure the price of the Royal Purple certified FC-W, but the Amsoil price is $7.80/qt or $7.40/qt at case price for comparison.
No need for synthetics in this application. Rotella Dino 15W-40...inexpensive, readily available, works great.
Originally Posted By: lsd6988
Originally Posted By: chad8
The FC-W standard was introduced by NMMA after the amount of anti-wear additives in automotive oils was reduced in 2006 in order to protect catalytic converters.
Most diesel oils would likely meet FC-W standards. But not modern automotive oils.
Because outboard motors have no catalytic converters additives can be used that can't be used in automobiles. So indeed the FW-C spec oil may have a better additive package or more additive than API spec oil for cars. BUT... outboard motors are different than car motors and could benefit from different or additional additives. Your typical car motor likely sees very little use over 3000 RPM. Most cars cruise down the highway at 60mph at less than 3000 RPM. Outboard motors can live a considerably larger portion of their life over 4000 and even 5000 RPM or higher.
Synthetics have hydrocarbons that are uniform and share similar sheer characteristics. Synthetics resist shear better than conventional oils for longer periods of time. In conventional oils some of the different size hydrocarbons break down earlier than others reducing the ability for the oil to protect the engine. Synthetics also vary in quality but that's for another topic. Just because a synthetic doesn't have a FW-C seal on it doesn't mean it does not meet the spec for FW-C oil. It likely far exceeds it.
Here's what I went with:
http://www.westmarine.com/webapp/wcs/sto...;classNum=50398
West Marine 10-30 Full Synthetic 4 stroke Outboard engine oil
Originally Posted By: chad8
It looks like all I could find was sierra and amsoil in a 10-30.
Amsoil is the better oil , I am sure.
There were no FC-W oils back in 2004.
The FC-W standard was introduced by NMMA after the amount of anti-wear additives in automotive oils was reduced in 2006 in order to protect catalytic converters. The latest automotive standards are even more restrictive. FC-W oils have more in common with 2004 automotive oils than the oils that are designed for modern cars.
Most diesel oils would likely meet FC-W standards. But not modern automotive oils.
Because outboard motors have no catalytic converters additives can be used that can't be used in automobiles. So indeed the FW-C spec oil may have a better additive package or more additive than API spec oil for cars. BUT... outboard motors are different than car motors and could benefit from different or additional additives. Your typical car motor likely sees very little use over 3000 RPM. Most cars cruise down the highway at 60mph at less than 3000 RPM. Outboard motors can live a considerably larger portion of their life over 4000 and even 5000 RPM or higher.
Synthetics have hydrocarbons that are uniform and share similar sheer characteristics. Synthetics resist shear better than conventional oils for longer periods of time. In conventional oils some of the different size hydrocarbons break down earlier than others reducing the ability for the oil to protect the engine. Synthetics also vary in quality but that's for another topic. Just because a synthetic doesn't have a FW-C seal on it doesn't mean it does not meet the spec for FW-C oil. It likely far exceeds it.
Try it next time. Highly recommended.You do realize Yamaha makes a full synthetic outboard oil.......
But if you want it cheap you are out of luck.
The only problem is it is not made by Yamaha, only branded by them.
Originally Posted By: SteveSRT8
The only problem is it is not made by Yamaha, only branded by them.
I have a f115 Yamaha. I plan on using napa 14 40 universal fleet oil (it is easy and cheap to obtain) most marine oils compare to this oil. should there be any problem with this? I also change oil at fifty hrs
Originally Posted By: rokwldr
I have a f115 Yamaha. I plan on using napa 14 40 universal fleet oil (it is easy and cheap to obtain) most marine oils compare to this oil. should there be any problem with this? I also change oil at fifty hrs
Hope I get that amount of hours on my f115. The napa 15 40 is a diesel rated oil. Most fwc rated oils are rated CJ4 just like diesel oil, and about 1300 ppm of zddp (zinc) which all flat tappet engines need. It is also made by valvoline. I use it in all my lawn equipment with no problems.
The Honda outboard tech I work with feels that regular non marine rated oils should not be used. I agree but don't have real world experience to back that up. That being said I don't think that running car oil, or HEDO is a slam dunk doable thing as a broad recommendation.
Depending on how you use the engine, and if it's stored for periods of time, salt water vs fresh water use etc.
The tech I work with tells me the cam lobes among other things get pitted with automotive oil. He did not elaborate on what use and storage the engine might have had with that comment. With that investment I would not be trying to save a buck on non marine rated oil.
He has been working on Honda outboards for I believe 10 years range.
napa 15w40 is a diesel rated oil but it is universal fleet. it is rated cj4 & sl which is what most fwc oil is rated. i believe most diesel oil will pass the fwc standard.
I switched from Yamalube to Penzoil Platinum 10W30 in my Yamaha F90 4 stroke - so far I am pleased.
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