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-   -   Fuel (http://www.rcuniverse.com/forum/speed-rc-nitro-boats-117/11125412-fuel.html)

wholehog 06-20-2012 10:18 AM

My motor manufacture recommends 20% oil. The problem with that is,my local hobby shops don't carry that blend in any of their brands or nitro percentages. The closest they have is 16% oil. Is 4% enough to make any never mind,or do I need to stay with 20%? Thanks

HendricX 06-20-2012 11:20 AM

RE: Fuel
Mix your stuff yourself ... methanol/nitro/and Klotz Super Techniplate ([link=http://www.klotzlube.com/proddetail.asp?prod=KL%2D100%5FQuart&cat=8]L I N K[/link])

And YES ... if engine-manufacturer requires 20% oil .. do so.

Sometimes the fuel-manufacturers also supply the oils they use , you can add that .

Bud ONLY use brand by brand .. don't mix .... some oils don't like eachother.

BUT : What is this NITRO question doing into the GAS section ? ;-)

wholehog 06-20-2012 12:01 PM

RE: Fuel
Thanks for the reply. By the way,I clicked on the wrong forum by mistake.

HendricX 06-20-2012 12:18 PM

RE: Fuel
You're lucky .... I do both .. ha ha

Dan S 06-20-2012 05:24 PM

RE: Fuel
you can use this calculator for mixing your nitro.
Scroll down at bottom of the page and pick which one you want to do.


Ron Olson 06-20-2012 08:42 PM

RE: Fuel
Most hobby shops get their products from two sources, Great Planes and Horizon Hobby so yes, they can get boat fuel from Great Planes which is part of Tower Hobbies. They can get AquaCraft's GrimRacer fuel which is good stuff in quarts or gallons. More than likely they would rather unload on you what they aleady have on the shelves. If they don't want to bother then you can order it yourself. If you buy quarts then there's no Haz-Mat fee but it's more expensive if you figure what you'd pay per gallon. With gallons you pay the Haz-Mat fee but the gallons are cheaper versus the quarts.
Heli fuel will do in a pinch but the nitro content is lower.

amax 06-21-2012 09:50 AM

RE: Fuel
Oil % in the fuel is one of Those Debates that have gone Haywire several times in the past but Here's My 2 Cents....

20% Oil in the fuel is the manufacturer trying to cover There Butt because it's harder to Burn an engine up by running To Lean with that much oil. You Burn off About 50% of that during combustion and about 90% of the rest goes out the exhaust because it can't burn that much oil in the short amount of time it's going through the combustion part of the Cycle, the rest if left clinging to the cylinder walls and the Bearings for Lubrication. Although having more than Plenty oil unburnt provides substantial lubrication it is also Robbing Performance.
1st: all that Extra Oil in the fuel mixture is taking up Space\Volume that Should be filled with Fuel, More Fuel= More Power.
2nd: Oil slows down the rate at which the fuel burns so your burning even Less of the fuel mixture in that very small amount of time during combustion, if the fuel isn't burning it's not making power, Plane and Simple.
3rd: Oil does not compress as easy as Fuel or Air, so it's takes more of the kinetic energy created from the combustion of the previous stroke for the piston to reach the top of the stroke for combustion, in turn providing less power to turn the prop and a Lower Maximum RPM.

4th: if the Oil Isn't burning it's getting dumped in The Pond and Polluting the water. The Oil in the fuel we run is the only part that's Not considered a Green Fuel, Both Methanol and Nitromethane will COMPLETLY Dissipate in water in 3 to 4 days,, Oil Does Not it floats on top of the water and sticks to anything it touches.

Ideally for Maximum Performance you want Just Enough Oil to provide what Will Burn Off during combustion and Leave Behind Just Enough to provide adequate Lubrication, Leaving a Light Smoke Trail behind the boat and not a Rainbow Colored Slick in the water,,, BUT running your oil% that low is MUCH Less Forgiving to the Inexperienced Tuner.

in another post I seen you stated, you were running the 1\12 Pro Boat so I'm assuming you have either the .15 Dynamite engine or the .18 Pro Boat Engine. I Have run Several of Both and 16% oil IMO is a fairly Safe level for a slightly experienced tuner especially if your running 30% or Less Nitro. I have run as low as 10% oil in both these engines and they Love It but That's Me, in my Modified Engines running much higher grade ceramic bearings I have run as low as 8% trying to Tweak Every Bit of Performance from the engine, But most the time I run around 12% Oil which is 80% synthetic and 20% Castor,,, and 60% Nitro[>:]

wholehog 06-21-2012 10:46 AM

RE: Fuel
My motor is an 18 pro boat. I went to the sight above about mixing you own fuel(quick easy formulas),problem is finding nitro that one can afford. Now that syn oils are so popular,do you still want one with castor in it also,or just run a straight syn oil?Thanks everyone for the tips.

Ron Olson 06-21-2012 07:36 PM

RE: Fuel
Wholehog, kind of a suggestion. Scroll down under the boat forums and there is a big one that can answer a lot of your fuel questions. Brian "Fuelman" Cooper hasn't been in here in a long time but you may find several threads related to all you want to know about nitro. I met Brian many years ago and found out at that time he only lived a few miles away from me. We talked one afternoon and this guy knows an amazing amount of info about nitro. The threads may be old but there's still a lot to be learned in there that still holds true today.

Blackout 06-22-2012 02:54 AM

RE: Fuel
If your LHS has Morgan's Omega airplane fuel, that works well in boat engines.

Just stay away from car fuel, they sometimes have real low oil contents.

toyotatruckin 06-22-2012 06:33 AM

RE: Fuel
I ran 12/40 and 12/50 for years and never blew an engine (due to fuel) Ive run everything from O'Donnell to redmax and some cheap blue crap that was on the shelf at the hobby shop, I was in need lol I mainly used 12/40(12 oil-40 nitro) as it was a good performing fuel with less wear and easier tuning than the higher nitro fuels

This kind of goes with what Adam said, There is NO fuel that will protect your engine from poor tuning

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