Double oil ok?

[Austral20]

Hi from down under. I have a 2009 8hp 2 stroke and manual says to run at 100:1 oil fuel. However the mechanic here recommends I run 50:1 to better protect the engine.

He said 100:1 is primarily for the US market due to tough emission laws. Will the 100:1 increase wear?

Thanks. Ray from Aus.

[boscoe99]

Hello from up over.

If 50/1 is better than 100/1 why not 25/1?

If blue locktite is good why not use red locktite.

If the torque value is 50 lb-ft then 100 lb-ft has to be just right.

Has your mechanic suggested taking out the pressure control valve to get the water pressure up? Does he recommend dialing up the oil pressure in four strokes?

It is a dangerous world out there. One cannot be too careful.

It continues to surprise me that there are so many mechanics that know more than Yamaha the engine maker. One would think I would stop being surprised.

[Nautical]

I think it a matter of expense..50:1 will probably give you a little more insurance if no maladies rear up like fouling plugs or excessive smoke.I don't think Yamaha was thinking of emissions during their design of a motor intended for world wide distribution, but who knows ?I know some guys put some extra in the fuel tank as a precautionary measure..

[rodbolt17]

if you will PROMISE to meticulously maintain the fuel and cooling system and if your going to let it sit over 30 days winterize it, then 100/1 is fine.
however your not going to.
I like the 50/1 mix myself and even OMC tried the 100/1.
100/1 works but wont leave enough oil behind to protect the shiney metal internal parts when stored over 30 days.

[boscoe99]

If 100/1 offers corrosion protection for 30 days, and 50/1 offers corrosion protection for 30 days plus Y days, does it follow suit that 25/1 will offer corrosion protection for 30 days plus Y days plus some more days?

Going back in time to my dads Mercury tower of power, I recall it being one quart of oil at 20 cents a quart to six gallons of gasoline at 29.9 cents a gallon. Give the man at the dock two bucks and he put a quart of 30 weight plus six gallons into the tank.

If my math is correct the oil ratio was 24/1.

[TownsendsFJR1300]

In addition to what Rodbolt posted, I would take into account how you use the engine generally.

IE, if running WOT or higher RPM's OFTEN, I'd go with the 50/1. If idling / *****ing most of the time, you'd be ok and less likely to foul a plug at 100/1.

All of my 2 stroke lawn machines mix NO less than 50/1, some 40/1 BUT their generally run very hard(chain saw especially), 7-8,000 RPMs...

And, all are run with RingFree as well....

[99yam40]

I have/had a couple of old sears/craftsman chain saws that called for 16 to 1 they still ran well after I went through the fuel and oil systems.
They sat around for many years with no one using them before I cleaned them up.
So my thoughts are yes the more oil the longer they will be able to sit without rusting the shiny parts inside.
I wish that SOB that stole one of them from my garage would have told the cops what he did with it.
At least he got a 2 year sentence for the tools he hocked and they found. I am sure he will not serve it all though

I would have preferred to have that 12" back that my Dad owned

[Austral20]

Thanks for the information US&A!

i didn't mention that the mechanic that suggestion to use 50:1 instead of 100:1 is from the Yamaha OEM dealer and is supposed to be Yamaha factory trained.

I am concerned that it would foul up the plugs quicker - although cleaning is not an issue, but breaking down is!

I think I will maybe increase slightly the amount of oil as to date the engine has run very well and the work shop said they did a compression test and it is almost as good as new.

The motor has moderate use as it is on a yacht, but if there is no wind it can work for a couple of hours in a row. I never rev it over 4000 and most of the time it is revving at around 3000.

Do you know what the max recommended RPM is?

Thanks again and I hope you guys are not freezing too much as we boil here in Aus.

Ray.

[TownsendsFJR1300]

i didn't mention that the mechanic that suggestion to use 50:1 instead of 100:1 is from the Yamaha OEM dealer and is supposed to be Yamaha factory trained.

I am concerned that it would foul up the plugs quicker - although cleaning is not an issue, but breaking down is!

I think I will maybe increase slightly the amount of oil as to date the engine has run very well and the work shop said they did a compression test and it is almost as good as new.

The motor has moderate use as it is on a yacht, but if there is no wind it can work for a couple of hours in a row. I never rev it over 4000 and most of the time it is revving at around 3000.

Do you know what the max recommended RPM is?

Thanks again and I hope you guys are not freezing too much as we boil here in Aus.

Ray.

Generally, the two strokes should max at 5,500. From what you posted, (it's healthy), your not dogging it and I agree, I'd personally mix a little more oil (just from experience with other two strokes).

My Poulan chain saw is mixed at 40/1 (run WOT most of time with a heavy load) and with that mix, will NOT foul a plug and idle all day long W/O issue.

**I would strongly suggest running Yamaha's RingFree. With today's crappy fuel and the added oil mix, it keeps the fuel system very clean as well as the TOP END/ rings, etc. I run it in EVERY GAS ENGINE (SUV too) I own.

I'll also add it to my customers machines(mostly cleaning carbs) for additional cleaning...

https://www.shopyamaha.com/product/d...?b=Search&d=34


.

[zenoahphobic]

Downunderers don't "winterise " outboards , so old protection only for storage!
I think the argument about oil fuel ratios, not only wise to increase oil percentage for heavy load but more so with max RPM . The faster a two stroke is run the more oil required. Model engine (radio control) users can quite confidently tell you that at 20,000 RPM 10:1 is used!!
They know from experience because they use engines like Zenoah (my namesake) to the absolute limit before destruction, that no less oil these engines will long earlier fail.
Of course the fuel system needs to be enriched to cater for the displacement of the burning fuel with non burning oil.
As far as fouling of plugs, this rarely is a problem if the engine is cooled to stop burning of the oil, but just warm enough to support combustion.
I must say engines are not designed to a particular oil fuel ratio, but rather to meet emissions. However if an engine blows up at lean 100:1 tolerances are slackened to stop engine from seizing.

[zenoahphobic]

I must add these engines use unleaded regular "gasoline" and quality synthetic or part synthetic oil used on any engine, and that the plugs look absolutely clean at 10:1 oil ratio, almost undetectable from any plug used at 50:1 or 100:1!

[rodbolt17]

freeking blowboater
wind is free and everything else outta be.
Yamaha, like most other brands, defines long term storage as any period of non use over 30 days.
that's in your manual as well. read it.

running correctly 50/1 wont foul plugs any faster than 100/1.

biggest thing is MAINTAIN your rig or pay double.

[boscoe99]

freeking blowboater
wind is free and everything else outta be.
Yamaha, like most other brands, defines long term storage as any period of non use over 30 days.
that's in your manual as well. read it.

running correctly 50/1 wont foul plugs any faster than 100/1.

biggest thing is MAINTAIN your rig or pay double.

Evinrude says no maintenance required for three years. Apparently, just add oil and go.

[bajakeith]

LOL "The wind is Free"

Right on Rodbolt !! I'm not prejudiced..*****ed from mex to Alaska on a rag boat,,,BUT, maybe 1 out a 100 sail boat calls I get, do I actually even go to the boat...Freaking cheapskates.. and this seems to be the world over..what---spend money on the iron genny.. cant you JUST Make it work for a ten spot and GOD knows the wireing on sail boats are a joke..And guess who always tows them in.....A power boat !!

[TownsendsFJR1300]

I got my popcorn and was waiting for the "blowboater" posts!!