Well, its finally official on Koh Phangan, the local PTT is now only offering 95 gasohol. So, does anybody know what kind of effect using it will have on my husband's 2 stroke 15hp outboard engine? Does he need to modify anything? Does he need to change the gas/oil ratio?

Well, its finally official on Koh Phangan, the local PTT is now only offering 95 gasohol. So, does anybody know what kind of effect using it will have on my husband's 2 stroke 15hp outboard engine? Does he need to modify anything? Does he need to change the gas/oil ratio?

I don't know about all the two stroke outboard engines, but Yamaha doesn't recommend gasohol. They will run fine on 91 octane gasoline.

Agreed, I don't recommend using gashol. It should run just fine with 91 octane and there is no need to alter the mixture. If, on the off-chance, you suffer a large loss in power or severe 'pinking' then maybe alter the timing but you should be able to run fine

Thanks guys, it is a Yamaha, so that is good to know.

Hello

Do NOT, EVER, run a two-stroke on Gasohol!! Think about it. What is the best stuff to remove oil? Correct, Alcohol. What does a two-stroke live off? Correct, oil mixed with the gasoline.

So what does Gasohol do to a two-stroke? Correct, killing it by dissolving the oil.

However i doubt that your two-stroke is so highly compressed that you need to run it on 95. It should run just fine on 91. If not time the ignition a tad bit later.

I once (only once!) tested my Yamaha RXZ (135cc two-stroke) bike with 95 - it used MORE gas than when using 91, the power was exactly the same tough (no better, no worse).

Best regards.....

Thanh

<edit> double post deleted

Hello

Do NOT, EVER, run a two-stroke on Gasohol!! Think about it. What is the best stuff to remove oil? Correct, Alcohol. What does a two-stroke live off? Correct, oil mixed with the gasoline.

Absolute rubbish! You CAN run two-stroke on Gasohol (ethanol) It DOES NOT remove oil.

You can mix it with regular as well if you are worried about that. Ethanol burns slightly cooler that petrol so mileage is slightly reduced and if left for some time, the ethanol may rise to the top of the oil. But a quick waggle of the boat and it will mix again.

So what does Gasohol do to a two-stroke? Correct, killing it by dissolving the oil.

wrong, wrong, wrong. Ignore this guy, he doesn't know what he is talking about.

We have the same problem with our Rotax-powered small aircraft here in Thailand. We need 95 octane non-ethanol fuel. Fortunately, it is still available at gas stations other than PTT. Check with Yamaha. I think the website for watchara marine dot com will have some specs and phone numbers in Thailand you can call regarding their Marine engines. In our airplanes, 91 octane gasoline is the only choice; never gasohol!

Hello

Do NOT, EVER, run a two-stroke on Gasohol!! Think about it. What is the best stuff to remove oil? Correct, Alcohol. What does a two-stroke live off? Correct, oil mixed with the gasoline.

Absolute rubbish! You CAN run two-stroke on Gasohol (ethanol) It DOES NOT remove oil.

You can mix it with regular as well if you are worried about that. Ethanol burns slightly cooler that petrol so mileage is slightly reduced and if left for some time, the ethanol may rise to the top of the oil. But a quick waggle of the boat and it will mix again.

So what does Gasohol do to a two-stroke? Correct, killing it by dissolving the oil.

wrong, wrong, wrong. Ignore this guy, he doesn't know what he is talking about.

Oh yes, ignore me.

Dears, i have probably more kilometers on two-strokes under my ass than you have in any form of transport, including trains and aircraft, combined. I spent a large part of my life so far maintaining, rebuilding, repairing, tuning and restoring two-stroke engines anywhere from 3 to 750 cc. I still drive a two-stroke daily in Bangkok today, 300 kilometers a week in fact.

If that is all worth ignoring, do a quick google on "two-stroke gasohol" and believe others, specifically the engine manufacturers and users from areas where gasohol is common, here specifically U.S. marine users (marine as in "boat", not as in "soldier"). EVERYWHERE you'll hear of catastrophic engine failures due to the ethanol in gasohol doing what it does best - cleaning that is - on the needle bearings in conrod, piston bolt etc and thereby, yes, KILLING the engine.

If that's all worth ignoring, go right ahead and put it into your tank. I am happily assisting you in changing your crankshafts, pistons and scratched-up cylinders. But do NOT say "but nobody warned me...." later!

Best regards.....

Thanh

PTT the biggest petrol retailer announced Mar 4th that they will stop all sales of regular 95 gasoline nationwide following the lead of Chevron and JET .

Analysts say that sales of 95 will be affected at other outlets as PTT is the biggest local refiner and distributer.

The government has made it very clear that 91 petrol will be replaced by gasohol.

Only in Thailand where vested interests overrule sanity.

Quote of the year from Chakrit Charuchinda, VP for Retail Marketing, PTT

"For owners of cars older than 12 years that need premium petrol. we are sorry about that"

By the governments own calculations there are 500,000 car owners (they ignored motorcycles), including owners of brand new cars like Ferraris for example, that are a tad sorrier