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Unleaded premium/Ethanol gas


Rick3410

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Just topped off my tank with premium unleaded. Thought I'd see how the old cast 16HP would run on that. Man, what a mistake. Now it's running like crap! I can't get it to start for anything, the idle is terrible, backfires alot and serious loss of power. Is this typical and should I be even using unleaded in this thing? I figured it was made in the seventies and all new vehicles (at least cars and trucks) were mandated to use unleaded. Or is premium with ethanol the problem? Folks, I'll use whatever works best. Someone please let me know what's going on. I've reset the points and cleaned them, adjusted the carb and it still runs lousy. When it's warmed up I can get it adjusted to run OK and have enough power to mow. Let it cool down and it becomes extremely difficult to start.

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The high octane fuels are not needed in our engines, as you found out. Octane is there to delay the ignition of fuel. Our engines do not have high compression so there is not enough "pressure" to properly ignite the fuel. I have a high(er) performance motorcycle. It's about 110 HP out of 1200cc. It actually gets better fuel milage on regular fuel as compared to premium fuel.

Now if you were to shave the cylinder head, change the cam timing & lift, it's possible you could take advantage of the high octane fuel.

Ken

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I use premium unleaded with out ethanol in everything string trimmers mowers chain saws tillers leaf blowers. No problems

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So the higher octane would explain why the power is still there and why it has become difficult to start. I can't believe how lousy this thing runs. I don't think the ethanol is helping any either. Although I will say that I was using 87 octane with ethanol before and it was running fine.

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I put E10 in everything I have and have had zero problems because of it. 70 year old tractor sits over winter with E10 and it'll hand crank and start on the 4th pull. B10 and B110 will pop right off and run great. Zero turn mower sits all winter and starts perfect in the spring. The cheapest gas at the pump you can find is probably better than what these mowers burnt when new.

b110guy

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So you don't think that the ethanol is contributing to the problem. I tend to agree. I thinking the octane and it's firing requirements per Kenh is probably the root cause to the poor performance. Has anyone else had this happen to them?

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Harley put out some info about ethanol being hard on rubber and robbing a little power and that it is not as stable as gas w/o it. I always run regular in everything, and like Kenh said, my engines can't use the higher octane. It is hard to find any fuel around here with no ethanol in it.

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If an engine can't use the higher octane, can using it cause the deterioration in performance that I have experienced? Or, do I need to be looking for a deeper problem?

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I always run premium (and it has the ethanol in it) in all of my equipment and have never had problems. Al Edens recommended it strongly. I would think there is something else going on, but all I can say is, try regular fuel and see if the problem clears up. If not, then you know there is some other issue.

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I use premium in all our tractors ethanol free. They all run fine. The reason I stopped using the ethanol gas was my son has a Toro mower they use around the shop and they put ethanol gas in it. After the third tank it wouldn't start. I drained the gas and put premium without ethanol in and pull it a couple times. Left it set and came back a couple hours later and it popped right off. The extra cost is worth it. BP Amaco and Kwik-Trip both have ethanol free premium in town.

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High test gas is for high compression engines for most gasoline engines regular is what they need.High octane means its slower to ignite than regular this is needed in a high compression engines to keep them from going off like a diesel before the piston is in place where the plug fires.In a regular compression engine High Octane gas is harder to ignite and doesn't burn as clean and carbon build up will the result.As carbon builds it then will cause its own set of problems.Not only are you wasting money on high octane you're also causing yourself problems.

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We've always used the cheapest gas at the pump as well, Never had a problem in any of our engines, although I won't run a Briggs so I have no input on that, but in the old K series singles, Magnum twins, and our Commands, they run flawlessly for us on regular grade.

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quote:Originally posted by Rick3410

If an engine can't use the higher octane, can using it cause the deterioration in performance that I have experienced? Or, do I need to be looking for a deeper problem?


id="quote">
id="quote">Higher octane won't hurt your engine------nor will it help your particular engine. A several things that could be your problem. One is that you simply got some bad fuel.If you have been using non-ethanol fuel, there could have been some accumulation of water in the bottom of your fuel tank. Putting E10 into it could have absorbed enough water back into the fuel to cause problems.Again, if you have been using non-ethanol fuel, you could have a bunch of varnish and rust in your fuel system. The ethanol would start to dissolve that varnish and rust and cause blocked fuel filters and carburetor passages.Empty your fuel tank. If it is brownish or cloudy in color, clean the tank as best as you can and refill with either E10 or regular gas. If you keep using E10, your fuel system will stay clean and rust free.
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High octane gas burns slower than the lower octanes. For an engine to need 93 octane it should have around 10:1 compression. Our engines only have around 6:1 compression. They do not need high octane, and because it burns slower, a significant portion of the high octane will not be burned and will be dumped out the exhaust. Octane requirements are related directly to compression ratio.

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The premium gas has 87 or 89 octane not much different from regular

but it does not have ethanol in it

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Originally posted by Ronald Hribar

The premium gas has 87 or 89 octane not much different from regularbut it does not have ethanol in it

id="quote">Ethanol has some serious side effects for older fuel systems - but it is here to stay, and usually the problems can be worked out.
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The premium I bought said 93 octane on the pump. I'm gonna drain the tank and run a tank of regular unleaded and see if that solves my problem.

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There is very little gas available around here. I can get some at an airport about 25 miles away.

E10/87 tremendously outsells high test E10. Stale E10 is to be avoided.

Vapor pressure is now a days designed to be lower so it makes starting harder.

good reading:

http://www.goldeagle.com/UserFiles/file/STA-BIL%20files/White_Paper_Ethanol_%20Blended_Gasline.pdf

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Around here they sell 87,89, and 91. BP started selling their premium without ethanol and Kwik-Trip started a while ago. Been using it for a long time with no problems and will continue to use it. Don't have any winter starting problems either.

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quote:Originally posted by Ronald Hribar

The premium gas has 87 or 89 octane not much different from regularbut it does not have ethanol in it


id="quote">
id="quote">Some stations out west there in Oconomowoc do not sell blended premium gasoline. I check the pumps here in Waukesha and the Premium gas still is blended E10.Advancements in a car's OBDII system have pretty much negated the need for Ethanol in fuel.
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I burn what's cheapest never had a fuel issue.

I believe these old cast iron brigs would run on buttermilk

once you got them wormed up.^:D

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FWIW.... At one time Marathon was selling "sub octane" fuel and added ethanol to bring it up to the minimum standards. I don't believe there were any additives (detergents) in the fuel except the ethanol.

Things may have change in the three years since I've heard that "rumor" though.

Ken

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I think the engines may need whatever they were tuned/adjusted to use??

I have NEVER used anything other than Reg/unleaded with 10% ethanol. Before that Reg/leaded. In 30 years I've never had a fuel related problem in any of my outdoor equipment.

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