synthetic oil 2007 115 hp

I have a 2007 115 honda and thinking of putting synthetic 10w30 oil in it. I troll for salmon with it at 800 rmp most of the time and was wondering if this will be a good choise.

Re: synthetic oil

In general synthetic oil is the best for lubricating, but.
Marine engines have a tendency of getting moisture (water) in the oil, particularly raw water cooled engines running at 60++C. Unless you manage to get the oil temp a bit above 'boiling' (100C) (most automotive synthetic oils do not have the ability to absorb those small water droplets), the humidity will not evaporate.
If you find a 'marine' synthetic, then ok, but not a std automotive oil.

Re: synthetic oil

Honda does not recommend synthetic oil in the engine. It takes a good 700 - 800 hours for the rings to seat properly. Using synthetic oil will inhibit the rings from seating and essentially your motor will not ever break in and you may have runability problems.

Unofficially after that time, synthetic is ok...but you still have to change the oil at the standard intervals.

Personnally, I would stay with the oil that is recommended in your owner's manual.

Re: synthetic oil

My 2002, 9.9 HP Honda Owner's manual reads;
"Use a 4 stroke motor oil that meets or exceeds the requirements for API service classification SG, SH or SJ. Always check the API service level on the container to be sure it includes the letters SG,SH or SJ. Engine oil is a major factor affecting performance and service life. Use 4 stroke automotive detergent oil."

There is no mention about synthetic oil. My sailboat is at a marina in St. Petersburg, Florida where humidity levels are always high and after 8 years, I have had no oil related problems while only using Mobil 1, 10W-30.

Re: synthetic oil

I would suspect that you are running higher RPM on your sailboat when using the engine. Not too many sail boats around here use the sails unless they are in a regatta(?) Higher RPM will get rid of a little moisture, so consider your self lucky.

Re: synthetic oil

On the contrary, I only use my engine to get in and out the marina. Sometimes I wonder if the engine fully warms up. My comment was because Hondadude stated that Honda does not recommend the use of synthetic oils on their engines. After looking at my manual, I did not see any mention about synthetic oils so, I checked the manual for a Honda 225, please see the link below. There is no mention about synthetic either. If Honda does not mention it on their owner's manual, where do they advise their consumers not to use synthetic oil.
Below is the link to the 225 owner's manual.
http://marine.honda.com/pdf/manuals/31ZY2601.pdf

Re: synthetic oil

There are no differences in lubrication demands for this engine and car engines. Most of the critical components comes from the auto engines.
RUNNING the engine on synthetic is not a problem.
What may be a problem is that these engines are not run as regularly as your car and the 'storage capability' may not be as good as the mineral ones! Among others its ability to absob moisture.
Using your engine more or less daily, just run synthetic.
Using your engine perhaps once a week or even at bigger intervals, I would not go synthetic.
Any oil SG or above (SH,SJ.....) may do. That is the lubrication demand for a running engine and not a stored engine.

Re: synthetic oil

I got interested by the question and found this: Synthetic oil myths.

http://www.synthetic-motor-oil-change-and-filters.com/amsoil_articles/myths-of-synthetic-oils/

Keep in mind that it is written by an Amsoil marketing guru.

I think what hondadude was trying to point out is that Honda "doesn't recommend" synthetics. Conversely, Honda "doesn't prohibit" or "advise their consumers not to use synthetic oils" either.

I'm a mechanic that has taken and passed many ASE certification tests including;
L-1 Advanced engine performance/gas
L-2 advanced engine performance/diesel

And I'm still trying to make up my mind. I speak regularly on the subject with people that I consider much more knowledgeable than myself and I still can't find a reliable consensus.

But, when it comes to breaking in a new engine, I will agree with Mike (hondadude). Use a petroleum based oil for piston ring seating and switch to synthetic after a proper break in interval.

Re: synthetic oil

I think it would depend om the mfg. I just bought a new VW JETTA and it came with synthetic and the owners manual says it is good for 10K miles. I got a letter from the local dealer telling me it was time for an oil change, hardly as I only have 5 k on it and told them that, the service managers' comments were that they like to see it changed every 5k, but of course the owner pays, even though it has 3 years full service provided by VW. My point being, you have to be aware of the service reps as they are trying to drum up business at the owners expense.

Re: synthetic oil

Regardless of whether you use synthetic or petroleu-based oil, you need to change the oil evey 100 hours or annually, whichever comes first. Under those circumstances, synthetic is a waste of money.

I distinctly recall reading that Honda specifically recommends petroleum-based oil. Whether it was in the owner's manual or the shop manual, I do not recall.

Re: synthetic oil

No outboard manufacturer lists a pure synth oil as approved...No manufacturer lists a pure synth oil as forbidden....One did list it as a no, no, up until about six months ago(They got tired of explaining why synth was a bad idea and took the caveat off their website) The reasons not to use synth have already been listed....There is no justification in using synth other than for high RPM commercial use where fuel dilution of the crankcase oil does not occur. Is synthetic oil a better oil? Yes, absolutely, no doubt, it is a much better lubricant. But, think for just a second what that means.....It reduces friction. Now think what a reduction in friction brings....A reduction in temperature....Now think what that means on a raw water cooled outboard engine running at a low RPM....Yes, your right, fuel in the crankcase. Since the advantage to synth is increased interval between oil changes, something that is now removed from the benefit side due to moisture in the marine environment, there is no economic justification for its use. Remember, your oil in an outboard should never be dirty as you are not running it where dust and dirt will get into it. You change it due to contaminates like water and fuel. Can you use synth it anyway? Yes, you can. Are you going to harm your engine? Almost certainly not...As long as you do not idle for excessive periods of time. Won't the fuel just burn off when you bring the idle back up? Yes, at the exact time where the synthetic oil would normally be doing some good, at high RPM, you will be running diluted oil that will eventually burn off....While you are getting excessive wear, which is why you were running the synth to begin with. Well then, why would anyone run synthetic oil in a 4-stroke outboard once this has been explained to them? We don't know. Some people get an idea into their heads and simply refuse to except reality. Does that make them stupid? No, it makes them hardheaded and since the likelihood of catastrophic failure from synthetic oil is remote they will NEVER have the kind of proof that they need to change their minds. So that means this entire load of crap was a waste my time and your time? Pretty much...But, it is my job to shed light where there was darkness. If people want to keep their eyes closed and put an extra year or two of wear and spend a few extra dollars on their outboard. I can live with that...That's how marine service departments make money

Re: synthetic oil

Tohatsu_guru. Great explanation. I copied and saved in my files to send to others with the same question - attribution to you. Hope you don't mind.

Re: synthetic oil

I am old enough to remember the opposition to radial tires when they came out. It is not unusual to hold on to what our parents told us but nowadays, it is hard to find bias belted tires. Those were OK when we were doing 55 MPH on Dad's old Buick and those engines, would cruise at 2500 RPM's at 55 MPH and dinosaur lubrication was adequate. Today we have small displacement engines turning 4, 5 or 6000 RPMs for a prolonged periods and lubrication requirements are not the same as before.
Some of the myths about synthetic oils are quickly being proven wrong. One myth that is not true is that you can not use synthetics until your engine has broken in or the engine will not seat adequately. Every day you see more automobile manufacturers using synthetic oil in their engines, some will not honor the warranty unless you use synthetic. Some Volkswagens, BMW, Mercedes, Corvettes and other brands, will specifically, not recommend, but specify that you use ONLY synthetic oils or the warranty will be voided.

There is a lot of hear say about what I think, he said or what I read. Keep in mind that there are 3 versions to every argument. What I say, what you say and then, there is always the truth. Read your owner's manual and follow the manufactures recommendations. The engineers that built the engine know more than you and I do. If the manufacturer specifically tells you not to use synthetic, then don't. I have yet to see an owner's manual that tells you not to.
Time will tell!

Re: synthetic oil

Raul,

Think back to January of 1998 on "thehulltruth"....You have seen it, in writing on a manufacturer's website...Tohatsu removed the "do not use synth" warning due to questions as to why they were the only manufacturer who had the balls to say it, in writing. Some Podunk dealer somewhere said he lost a Tohatsu sale because the customer felt that their must be something wrong with Tohatsu's designs as no other manufacturer had it in writing...The guy went and bought a Mercury instead. The irony there is that the Mercury IS the Tohatsu
The marketing department felt that other manufacturers were letting them take the hit on the caveat...That and the factory oil has a synthetic component to it as well so they felt that it was just confusing people. Like I said, the damage, if any, is all on the back end of the service life so your never going to see the headline:

"Four-Stroke Outboards Blowing Up Due to Synthetic Oil Use"

Now the "myth" about the rings not wearing in is not a "myth", its a cold, hard fact. But, it is not so much the slickness of the synthetic. Rather, it's once again about the operating temperature of the engine during the traditional low RPM break-in process. You can use synthetic for break-in, but you HAVE to spend at least twice as much time at each time/RPM interval to get the rings to seat.

Remember, auto's have a closed water cooling system so what you can do with them does not transfer over to an outboard's much more sensitive open water cooling system.