speed1
New member
On a 6.5 hp , HF engine I did notget an owner's manual with it, should I use Premium or regular Unleaded gas, does it make a difference? Thanks...Bob
Fowler, you're lucky. Over here (at retail level) we average about 10 cents/litre more for premium vs regular unleaded. The difference adds up quickly.
Huh I was under the impression it was the same as ultimate deisel
Oh well that's what u get for never buying petrol from a pump
Oh well u say u won't notice the differences but when an auger is running for 14 hrs a day for 1 month we find the engines run cleaner in the end
Anyhow if its 5 c more then over a 44 gallon drum (205L) u only spend an extra $10.25
Like I said, some higher octane fuels use less ethanol in their mixes. That seems strange to me, since ethanol does a great job of boosting the octane rating, but it is sometimes the case.
I had attempted to determine the actual energy loss from running 10% ethanol by volume with stock jetting, but gasoline mixes vary widely depending on season, location, and crude from which it was distilled. I could still attempt it, I would just need to do it several times over with different mixes to get accurate results.
My hypothesis was that because ethanol requires less air to fully combust, the result of running E10 with stock jetting was a poor a/f mixture, resulting in power losses greater than than 3.7%. One problem is that I would need to find out how much energy would be consumed when the products of ethanol's combustion combine with the un-used air.
I had gotten so far as to determine the volume of one mole of 2,2,4-Trimethylpentane, Heptane, and Ethanol. This was needed to convert the volumetric percentages of the gasoline mix to molecular percentages. The math required covers several pages, and that's only a fraction of what's needed. And in order to get accurate results, rounding has to be used as little as possible.
Just food for thought:
There are-
1,204,428,300,000,000,000,000,000 Carbon atoms
3,613,284,900,000,000,000,000,000 Hydrogen atoms
602,214,150,000,000,000,000,000 Oxygen atoms
in one mole of ethanol. One mole of ethanol is 58.388390367553865652724968314322 mL
That bored, huh?J/K. Very interesting!

Speaking of which, anyone seen Robert around lately?
On a 6.5 hp , HF engine I did notget an owner's manual with it, should I use Premium or regular Unleaded gas, does it make a difference? Thanks...Bob
We are about 150c for deisel
And 140c for petrol
I think the aus $ is only a tiny but higher than the Canadian $
I love the technicality , wish I could understand it...I am so confused right now that I hope I never run out of gas...Thanks for all the answers...
Bob
It's fine , I love to lean and have done lot's of it in the short time I've been here ...Have decided to use Premium next time , it's a small tank...Sorry
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