2 cycle oil, water cooled vs. air cooled

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I don't have much in the way of 2 cycle equipment and don't often get this to part of the forum. I had a friend ask a question and I didn't have an answer. So I thought I'd post the question and we'd learn something. I apologize in advance if it's a newby question. Is there a difference in 2 cycle oil for water cooled (like an outboard motor) compared with air cooled (like in a dirt bike)? My friend was told the spark plug in an outboard motor would be more prone to fouling if 2 cycle oil for an air cooled operation was used. It seemed to ring true, since air cooled engines typically run hotter than water cooled engines.
 
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Your friend is right, however 2 stroke water cooled Snowmobiles and watercraft are very different than an outboard. You need a low ash oil for them
 
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I think marine 2 cycle oil has to be rated Biodegradable, verses non marine. Most quality 2 cycles oils are not biodegradable, especially racing oils.
 

CT8

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They are different especially in the additive package . To make things more interesting is there are dual use oils that seem to work fine. I have been using a dual purpose oil in my lawn equipment and chain saw with great results. The oil jobber used to sell M1 2 cycle oil and when I whined about the oil being discontinued he recommended the dual use oil and said the commercial ground services use it and get great engine life.
 
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Duel use oil is a compromise at best. I would never use one in my expensive snowmobiles or watercraft. Maybe for a lawnmower. As mentioned, TCW3 oils use a biodegradable (no metallic ash) additive package. Thats fine for an outboard motor.
 
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CT8

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I finally got around to this link I can't say it is gospel but it is really interesting as it compares different oils in an ultra light plane 2cycle engine and deposits from the different oil. ultra light
 

CT8

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Originally Posted By: FastGame
I would hope things have gotten better since 1994 ???
Think about the content of the article beyond the name brand of the oil. The article basically tells the differences between the oil ratings. Think!
 
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I've been thinking since 1994 and know what it says about the differences. Today's oils are better and may cross the boundary between ratings with the universal rated oils, or maybe not ?
 
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Originally Posted By: CT8
Think about the content of the article beyond the name brand of the oil. The article basically tells the differences between the oil ratings. Think!
I would "think" oils are different now than 20 years ago. And of course his results were only valid for his application.
 

CT8

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I would think the article explained some of the differenced in air and water cooled oils.
 
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Also, those ultralight engines are not highly stressed 2 strokes. They are made to be reliable, when properly cared for. Note: There are 125cc motocross racers that swear by TCW-III outboard oil. They make all sorts of claims of low engine wear, clean internals and low power valve deposits. However, the guys doing this successfully use an oil rich mixture ratio, have well tuned engines and often use race gas. I'm not saying TCW-III is the right choice for highly stress, and air cooled engines. But, it does work when done correctly.
 
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A lot of modern two strokes use their own oil, like Yamaha and Evinrude. Two cycle oil isn't just two cycle oil anymore.
 
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I'm going to go out on a limb and suggest you follow what the engine manufacturer tells you to use. My Husqvarna blower specifically says: "Never use two-stroke oil intended for water-cooled outboard engines, sometimes referred to as outboard oil." My Husqvarna string trimmer specifically says: "Never use two-stroke oil intended for water-cooled engines, sometimes referred to as outboard oil (rated TCW)." My LawnBoy push mower specifically says: "Do NOT use use automotive oil (i.e., SAE30 or 10W30), a two cycle oil that is NOT NMMA TCW-III certified, or a fuel mixed at the wrong gasoline/oil ratio." And my last piece of 2-cycle equipment is a cheapy Poulan chain saw that says: "DO NOT USE AUTOMOTIVE OR BOAT OIL." So one piece of equipment says to use boat oil and the others say not to use it. They're all air-cooled outdoor power equipment. My point - RTFM!
 
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Technical articles have made it clear that TCW-3 oils may not be suitable for many air cooled engines for a simple reason: Outboard engines are water cooled and the thermostat temperatures are often between 120 and 140 degrees. This allows for the use of some very effective and desirable anti wear additives.....who's only shortcomings are that they loose their effectiveness at the higher temperatures that air cooled engines often operate at. Yes, I have noticed that some air cooled engines allow TCW-3 oils....my chain saw does. I also notice that it blows large volumes of air through the fins, and the head never gets too hot to touch. Outboards certainly need the best they can get.....it seems common for someone to mount a 35 hp motor on a pontoon, push the throttle wide open and leave it there for long periods of time.....maybe an hour when cruising from lock to lock on the Mississippi. Like FowVay says, RTFM!!
 
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not once in 25 years of commercial lawn service have i had an oil related failure using twc3 oil. dont use it in sthil 4 mix engines.
 
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not directly related but interesting... my local Piaggio-Vespa-Aprilia dealer sells and services Aprilia SR-50 2-stroke scooters that cost over $3k; they sell and fill new scooters with Valvoline Multi-Purpose 2-stroke oil: http://www.valvoline.com/products/brands/valvoline/small-engine-oil/18 they have manufacturer's approval or they couldn't do it; I find the choice odd considering they are using Mobil 1 0w-40 synthetic oil in all of their 4-stroke scooters (again with manufacturer's approval) another local shop that sells Genuine Scooter Company products splits their decisions between 2-stroke oils... older 2-stroke scooter designs (Stella or older Vespas) get BelRay 2T conventional: http://www.belray.com/bel-ray-2t-mineral-engine-oil newer 2-stroke scooter designs (Roughhouse 50 or Buddy 50 or Rattler 110 -- discontinued model) get Amsoil Synthetic Injector Oil: http://www.amsoil.com/shop/by-product/mo.../?code=AIOQT-EA or Amsoil HP Marine Synthetic: http://www.amsoil.com/shop/by-product/mo.../?code=HPMQT-EA another local Genuine Scooter shop sells multiple 2T oils from Spectro & Ipone; another dealer that sells Honda and Genuine scooters carries Honda 2T oil; another dealer that sells Yamaha, Honda, and Suzuki has all sorts of 2T oils by Spectro, Yamaha, Honda, and Suzuki! and those are just the injector or injector/premix formulas...several of those shops also sell various 2T premix only oils, 2T racing oils, and even 2T castor-based oils as a prospective owner of a new 2T scooter in my near future I am very confused...many multipurpose injector oils meet the warranty specs of the air-cooled scooters I am considering!
 
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I can tell you from tearing many Polaris two stroke engines down. TCW3 oil is bad for air cooled engines and I don't believe the two stroke motocross racers. The "Boat" oil leaves very hard carbon behind and have seen it freeze up rings solid several times. Look for a TC only rated oil with FB,FC of FD ratings. I have had much luck with Yamalube 2R. Stay away from Marine oils.
 
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