Synthetic Oil

[Cape Codder]

I Have A F50 Yamaha And I Just Did My 10 Hr. Oil Change. I Used 10w-30 Amsoil Synthetic Marine Oil. Also Used Marine Gear Oil For The Lower Unit. Very Expensive Compared To Regular Oil But Its Worth It. Never See Any Discussion On This Site About Synthetic Oil. Anybody Use It?

 

[Dave LeGear]

Their have been several discussions on it's use, just punch in the words "Synthetic Oil" or "AMSOIL" in the site search tool and you can read several

 

[Cape Codder]

Thanks Dave.

 

[MolarBoater]

I use Suzuki products in my Suzuki motor but have to mail order and wouldn't loose too much sleep over different brands of similar oils.

 

[Cape Codder]

thanks for taking the time to reply.bill

 

[Cincinnati]

My mechanic told me not to use synthetic oil in my Honda. He said that the regular oil helps prohibit 'making oil'. That is, keeps the piston rings seated so that there isn't fuel blow-by into the crankcase. He says that synthetic lubricates too well and allows fuel mix into the crankcase oil. Either way, you can't go wrong with using regular oil changed every 100 hours or less.

 

[Cape Codder]

some say o.k. others say no way. nothings ever easy. thanks for taking the time to reply to me.bill

 

[rockman]

syn.oil for cars ok, boats no. moisture is a problem reg oil absorbs some no problem. syn does not. moisture will cause crankcase acid build up in 4 strokes.

 

[Cape Codder]

In Yesterdays Mail I Received A Brochure From Yamaha Suggesting I Use Yamalube 4-m. In The Brochure It States Its Properties Are Basically Synthetic. The Price Is More Than Twice That Of Fossil Oil But Less Than Amsoil. I Will Be Using Yamalube In My Yamaha For All The Warranty Issues. This Is My First 4 Stroke And Research From You All Has Been Very Helpful To Me. Thanks For Your Reply.bill

 

[Dave LeGear]

There is only one “sure” way to remove moisture from the oil (no matter which type) and that is through the application of heat to the oil. That is why it is critical that your engine thermostats work as designed, and that you run the engine both long and hard enough to "boil off" that moisture before engine shut down, this no matter what is in the crankcase…

We have to understand though the end game in certain people telling you one thing or another when it comes to engine care. Some mechanics (I'm being kind here) are sly and realize that don't get paid as much to change your oil as they would installing a new power head AND (worse yet) will get paid even more labor dollars to install that power head AFTER the warranty has expired so keep that in the back of your mind when hearing recommendations for sure.

The Outboard makers though do know what can happen when oils that do not contain the correct additives (automotive use grades) for the intended marine environment can do to your engine. That is why the recent push to produce oils that have such additives by the OEM’s. There can be though a large difference though in thermal breakdown and lubricity properties and (even more important) deposit levels left behind between the two oil types be it either a 2 or 4 stroke engine. Now if you plan on keeping your engine for a long time, (or for the re-sale value if you do not) then the use of Marine Grade Synthetic oils is a logical route...

Oil (shocking as it may sound) does not wear out, but becomes diluted with fuel, dirt, and deposits over time and it is during that time period (between your oil changes) is where you need to "choose" just how much engine wear you are willing to have occur on your engine? Like the old FRAM ads use to say "You can pay a little now or a lot latter" still holds true

25 years ago I worked on huge engines that rarely had oil changes (just additions) then again, how many engines do you run now that have lube oil pre-lube pumps installed (oil pressure to 30 plus PSI before it was even turned over) and purifiers that sent the oil through a centrifuge to sling out all the crud and deposits and clean oil was always sent back into the engine on each lap and that is why, those engine’s lasted for generations… Engine start up with zero oil pressure though is where you get the majority of your engine wear and is very hard to combat on any engine that does not have a pre-lube pump to get all that "motion lotion" flowing before crank starts to spin.

So post engine break in period and after your standard warm up, if you are running the engine long enough to remove the moisture (some period of or near WOT running before shut down) and are changing the oil as recommended, then for me the choice is clear and I will run synthetic. I though have never heard of it being possible for a synthetic oil to be "too slick" for rings too seal (which by the way, is not the rings primary job)... for if it was, then my fuel burn rates should drop by huge amounts (which they don't) from all that lost heat and friction from using such, true?

More information though on this interesting subject and the fairly recent release of “Marine Grade” synthetic 4 stroke oils can be found here http://www.amsoil.com/StoreFront/wcf.aspx for your viewing pleasure.

Enjoy!

 

[Cape Codder]

Hi Dave-once Again I Thank You For Your Clear And Concise Explaination ,this Time On Synthetic Oils. Sure Am Glad Your On This Site.bill

 

[Cincinnati]

I would suspect that if synthetic was then 'end all', then my Honda manual would recommend synthetic oil - it doesn't. No, I think that Amsoil, Mobil 1 and the bunch are just printing money every time someone buys a quart of full synthetic crank case oil...

 

[Dave LeGear]

The OEM's cannot insist on one brand of oil or filter over another unless they are willing to supply it for free. This is from some law that was put into place some years back though for the life of me cannot remember it's name since I got out of that businesses years ago.

Honda though does not discourage it use and (just like the AMSOIL page before) only recommends that the oil meet it's weight and additive requirements in your manual http://www.honda-marine.com/faq_8.aspx and still get changed at the same time period.

As I has stated in the past, it is your engine and you choose to run in it what you feel is best Synthetic oil though is not some kind of acid that eats though metal (just your wallet when you go to buy it ) as some would have you believe it is...

 

[Cape Codder]

Cincinnati-thanks For Your Thoughts On This Subject. I Love The Free Expression Of Ideas On This Site. I Suspect The Reason Honda Manuals And My Yamaha Manuals Dont Encourage The Use Of Synthetics Is Boaters May Become Complaisant With The Long Term Capabilities Of Syn. Oil And Therfore May Not Change Oil At Specified Intervals. One Of The Big Selling Points Of Syn Oil Is Its Longevity. Dont Forget Who Writes These Manuals.............lawyers. Anyway,just My Thoughts.bill

 

[Cincinnati]

Agreed Cape Codder. It's tough when guys like us who do not work on boats for a living, rather, use them on the weekends try to do maintenance ourselves. Everyone has an opinion on what is best, etc. Somewhat off topic, but last year I purchased an aftermarket fuel filter from a reliable brand name company. Turns out, the glue that held the filter element in place disolved when it came into contact with the 10% ethanol in our CT fuel. The glue traveled into my VST and stuck the needle open - flooding it and sending raw fuel out the vapor recapture. I noticed it when there was a rainbow trail behind the boat approaching the dock. I sent my mechanic's report along with the old filter back to the company and they refunded me the entire $400 repair bill (which included a VST and fuel system cleaning). Went back to a Honda filter and had no further issues. Since, I'm just not comfortable using anything but OEM. Likewise, I use regular automotive 10-30 oil and change it frequently. Some guys go out and buy a Honda Accord oil filter for their marine engine. That is a also a mistake, the marine filters have a different design and seal... just some additional thoughts.

Big Dave - you know we're buddies.

 

[Cape Codder]

Cincinnati-your Right.stick With What You Know,and In My Case, When It Comes To Marine Engines , I Dont Know Much. My Plan Is To Take Your Advise And Dave(putershark) And Everybody Elses Advise. Use Yamalube 4-m (basically Synthetic), Change It Often And Scream This Boat Back To The Ramp. Life Sure Is Simple When You Listen More Than You Talk. You All Have Been Terrific And I Thank You.bill