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hoss_the_hermit

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"Was talking w/ a gentleman th

"Was talking w/ a gentleman the other day about my outboards ('53 Lightwins) and was told that with today's TCW3 oil I should be running 1 pint to 4 gal. of (minimum 89 octane) gas, instead of the pint to 2 gal.(87 octane) that I am running now. Let me add,this man has been running a highly recommended marine engine shop in the area for the last 30+ years. Any thoughts?"
 
"Any chance he is trying to se

"Any chance he is trying to sell you a new engine?

Your motor should be running on mix at 24:1 - according to OMC. Yes, the new oil is better and produces less smoke etc, but that really shouldn't affect the ratio.

I have read a number of opinions on which octane to use. OMC calls for 86 or greater octane. The opinion is pretty solid that you shouldn't use 91 or premium unless called for by the mfg. That's because the octane is boosted by additives that are detrimental to outboards.

Mid-grade (89) is supposed to contain detergents that are beneficial (however, since the mfg doesn't call for this grade, I tend to take their word for it).

The only thing that may lead me to use the mid-grade gas would be if I was burning the new E10 (10% Ethanol fuels on the market).

All the major mfg's are in agreement. E10 gets old (loses octane to below 85) in a period as short as 3 weeks. If used they also recommend running stablizer in it "all the time". So in this case, if you tend not to burn your whole tank quickly, perhaps the mid-grade, stabilized would be the way to go.

Other than that - listen to the mfg - they make a recommendation for a reason...."
 
"Thanks a lot, Graham. But tha

"Thanks a lot, Graham. But that leads me to another point of confusion. There's 2 pints in a quart, 4 quarts in a gallon, 16 pints in 2 gallons, right? Doesn't that make it 16:1, or am I missing some convention?"
 
"My OMC notes state 24:1 for 1

"My OMC notes state 24:1 for 1964 and earlier models - 16:1 is a normal mix for air cooled engines.

Having said that, yours being 1953 models may have called for a 16:1 mix - perhaps Joe Reeves can step in here and confirm for sure..."
 
"Thanks a lot, guys. My reason

"Thanks a lot, guys. My reasoning when I first got these was the decal that said mix 1/2 pint sae 30 oil to one gallon of gasoline (I did use TC-W 3 instead). Haven't really run them much yet, less than a tank each, guess I'll see if they foul plugs on what's already mixed up and then go 24:1.Again, I appreciate the help."
 
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