2 vs 4 stroke glow fuel

Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:
USUALLY, that is all it is, HOWEVER, a lot of 4 stroke fuels are all synthetic oils. They say that castor oil will mess up the valves in a 4 stroke. I don't know. My Saito 72 is 3 years old and has about 2 gallons of 10% nitro with a synthetic/castor mix through it. I have had no problems at all. I use the same fuel for both my 2 strokes and 4 strokes. I usually run Byron's 10%, however recently I was given 4 gallons of 15% Cool Power, so I have been running that.
Yes, you can mix them, but I wouldn't. If you are going to mix them, I presume at least one of the jugs has been in use for a while. If the fuel in either jug has picked up water, you will be ruining all of the fuel. For storage, I would keep the jug tightly capped and in a cool environment (basement, etc ). If it is kept well sealed and cool, fuel should last several years (or more).

Byron's fuel out of Ida Grove told me that their 2 & 4 cycle fuel wa
the same, that they did was just put it in a different jug because som people wouldn't buy it if didn't say 4 cycle if that's the engine the had, I've burned their 2 cycle fuel in my OS 4 strokes for 1 yr's.without any problems or failures ahd I'm not good abou winterstorage or the use of after run oil. Garr
-- sandburr@fmctc. ----------------------------------------------------------------------- snipped-for-privacy@fmctc.c's Profile: this thread:

I've done a bit of reading about this topic. Conventional wisdom holds that fuel for 4-stroke engines should be 100% synthetic oil instead of Castor oil or a blend of synthetic and Castor oil. Conventional wisdom says that Castor oil can cause excessive build-up in 4-stroke motors.
This conventional wisdom flies in the face of the recommended fuel by most every major 4-stroke engine manufacturer:
Magnum recommends 20% Castor oil for break-in and 16% or more pure Castor after break-in. A partial blend of Castor oil is required for warranty coverage for Magnum 4-strokes.
Thunder Tiger's recommendations aren't listed on Ace Hobby's website, but Tower Hobbies' tech notes mention that 2-stroke fuel is recommended for Thunder Tiger 4-stroke engines, and not 4-stroke fuel.
O.S. doesn't require Castor oil, but it doesn't forbid it either. O.S. only recommends fuel with 18% or greater lubricant content. Synthetic, Castor, or a synthetic/Castor blend may be used. O.S. does note that certain 4-cycle fuels shouldn't be used because they have less than 18% lubricant content.
Like O.S., the folks at YS don't forbid or demand Castor oil. Synthetic, Castor, or blended lubricant can be used. YS recommends 20% to 24% lubricant content, however. Like O.S., YS recommends avoiding 4-stroke fuel with less than 20% lubricant content.
Of all of the major 4-stroke engine manufacturers that I checked, only Saito specifically recommended synthetic lubricants over Castor oil. Saito also recommends at least 20% lubricant content, and a mix of synthetic-castor oil is acceptable.
When actual manufacturers' recommendations are examined, in almost all cases the following parameters apply:
2-stroke fuel = 5% to 15% nitro content with 16% minimum lubrication, synthetic, castor, or blended lubricants.
4-stroke fuel = 10% to 15% nitro content with 18% to 20% minimum lubrication, synthetic, castor, or blended depending on manufacturer.
Is there a universal fuel? Sure! A fuel with 10% to 15% nitro and 20% synthetic/castor blend lubrication will work with almost any 2-stroke or 4-stroke RC airplane engine from any manufacturer. A Saito purist may scoff at the idea of of using blended lubrication, but even Saito says that 80/20 blended lubrication is just fine for their engines.

Ed,
Thank you for your informative post. Your delivery was fantastic too, btw : )).
CJ

Nice (accurate) analysis Ed - congrats :-)