SYNTHETIC OIL - Switch?

[dd716ted]

I have a 2003 Honda 50 HP outboard (135 Hrs) that I have used Petroleum based Oil in since it was new... The oil has been changed yearly regardless of hrs used previous year. Will it hurt anything or is it a good idea / bad idea to switch to a synthetic oil (Mobil One or equivelant) now or should I just stick with regular oil? Opinions Please...

 

[Nutt]

Re: SYNTHETIC OIL - Switch?

I have always gone to a synthetic but after that the rule of thumb is to not go back to standard oil.

 

[Tig]

Re: SYNTHETIC OIL - Switch?

I switched to synth for everything I own. My engines run quieter longer. I like that.
Some may say that if you change oil every year you are only using 10% of the synth and wasting it and/or money. (just a % I made up) If I short change synth in an engine I will use it in my old lawn mowers or snow blower. Personally I don't think of babying an engine as a waste of money. Same as washing a car isn't a waste of money. Just my opinion.
There are no technical reasons to not switch back and forth as you please.
Mobil say you can even mix if you are so inclined.
http://www.mobiloil.com/usa-english/motoroil/synthetics/synthetic_oils_faqs.aspx

 

[triumphrick]

Re: SYNTHETIC OIL - Switch?

I recently changed my F 115's over to Castrol Syntec 10-40. One of the Yamaha vendors on another forum has had many of his customers make the change and all have liked the results. Our rig runs about 200 rpm's faster at wot after the change. This boat is new to me, and I did not know what oil was being run previously.

 

[Primalurges]

Re: SYNTHETIC OIL - Switch?

I run synthetic on everything I own, except my outboards. Honda does not recommend using it. The reason I was given from a Honda rep. is that water that would otherwise blend and evaporate with regular oil tends to pool in synthetic which could in turn get pumped directly into bearings causing them to fail. Water in theory could contaminate the oil because of condensation and use in a wet environment.

 

[TOHATSU GURU]

Re: SYNTHETIC OIL - Switch?

The reason no outboard manufacturer recommends it is because it contributes to the fuel diluting the oil. Due to the raw water cooling system of your outboard they tend to run cooler than intended which causes the fuel to blow by the piston rings diluting the oil in the crankcase.

 

[triumphrick]

Re: SYNTHETIC OIL - Switch?

The reason no outboard manufacturer recommends it is because it contributes to the fuel diluting the oil. Due to the raw water cooling system of your outboard they tend to run cooler than intended which causes the fuel to blow by the piston rings diluting the oil in the crankcase.

Elvin, I see you are in my neck of the woods. Do you feel the same way for motors used down here? Maybe the increased heat helps us?

After changing my twins over, I have yet to see an increase in the oil level. I watch it religiously after all the posts about the Yamahas "making oil".

My thought on all this, as well as what I have heard is not to use synthetic on break in. But once past that point, say a hundred hours or so, you would be fine to use it....

 

[TOHATSU GURU]

Re: SYNTHETIC OIL - Switch?

The Yankee's get the worst of it But, we see it here as well. The harder you run your engine the better off you are with a synth. It's the idling that usually puts them over the edge. I run Mobile One in our vehicles, but I can't justify the synth in an outboard due to the frequent oil changes we recommend.

 

[Jake Windemere]

Re: SYNTHETIC OIL - Switch?

I use Amsoil in my outboards - after break in. The relatively low capacity of outboard crankcases means that the added cost of synthetics is not much of a sticker shock when compared to a full automobile crankcase.

http://www.amsoil.com/storefront/wct.aspx

 

[gss036]

Re: SYNTHETIC OIL - Switch?

[The relatively low capacity of outboard crankcases] My 225 Honda holds 8 qts in the V6.

 

[triumphrick]

Re: SYNTHETIC OIL - Switch?

My F115's will hold right at 6 quarts. That Castrol 10 - 40 is sold that way for about $32 at Sams....

 

[Jake Windemere]

Re: SYNTHETIC OIL - Switch?

The 50 horse holds 2.5 quarts with the filter, 2.1 quarts without.

That's a lot less than any automotive crankcase that I have owned.

Price is absolutely no excuse with the 50. Four bucks a quart for mineral oil about nine bucks a quart for Amsoil. Extra cost, maybe 14 bucks per change. Fourteen extra bucks a year?

Cheap insurance, IMHO.

 

[DECK SWABBER 58]

Re: SYNTHETIC OIL - Switch?

NAPA full synthetic (same as valvoline) is on sale right now at my local store for $2.99 a qt.

I'm going to run it in my 9.8 Tohatsu and change it just as often as conv. oil.

 

[Jake Windemere]

Re: SYNTHETIC OIL - Switch?

I can't vouch for the quality of NAPA synthetic, but remember that quality varies between manufacturers. The better oils, both synthetic and conventional have robust additive packages.

The ability of oil to lubricate and protect is a function of the additives, not the base oil. In general the main advantage of synthetic oil is consistency in viscosity regardless of temperatures, not necessarily protection.

Cheaply made synthetics are likely not much better than cheaply made conventional oils.

Whatever you use, make sure it meets the manufacturer's specs. Use marine grade oil for marine engines.

 

[ziemann]

Re: SYNTHETIC OIL - Switch?

Oil threads = The Hamster Wheel of the internet