Fuel

[Garf]

I am out of Castor so I bought a gallon of what was available locally. The best I could do was Omega 10% nitro with Castor/Synthetic mix. They won't tell you on the bottle how much oil in what proportions they use, so I went to their website to see what I could find out. Turns out, the oil is 17% total with a 30/70 castor/synthetic mix. Has anyone ever used this stuff right out of the bottle? It doesn't sound promising to me. It cost $19.80 including tax, out the door.

[Steve Helmick]

The components are measured by weight, so the oil is much less than 17%...more like 14% by volume. Nitro is much heavier than oil or alcohol, so it would be under 8%.  Add plenty of castor oil. Some call it "bug killer"....for a reason.    Steve

[Phil Coopy]

Garf,

I use it a lot, but I boost the total lube up to 22% with castor oil.  I buy my castor from Tower but you can get the same thing under the Klotz BeNol name from a lot of motor cycle shops.  I've use this method with everthing from Omega 25% thru 10%. Finally settled on 10%.  Works for me. For old engines (Fox, McCoy, etc.) I just boost to 28%. I've got a formula to calculate how much castor to add based on the starting volume and % of lube.

Phil

[john e. holliday]

At one time Omega Fuel the red stuff was all I could.  I just ran my engines a little richer.  Of course most of them were well broken in.  Never added castor until a couple of years ago when I was told to add castor.  They said 4 ounces to a gallon of fuel.  Could never get engine runs like I liked.  Even mixed it with new fuel as I was told later that was too much oil.  Wound up dumping it on some weeds and getting a new gallon of fuel.  DOC Holliday

[Frank Sheridan]

So DOC, what are you running now? And what engines are you running it in? I've got one gallon each of Omega 5% and 15% and I'll be using it in Fox 35s and Enya 35s, all of which have bushed mains. If adding four ounces of castor oil is too much, then what is the correct amount? None?

[Dennis Adamisin]

I ran stock Omega 10% in a LA 40, then a 45+ year old K&B 35 GH - ran great.  Clean and cool. 

IMO - Castor is overrated; note Doc's experience.  Add castor at your own risk, I do not think it needs it.

[EddyR]

I also have used it for the last two years in my Rustler/40 and my ST/46 that has the ABC conversion. I did all the testing work for Brian on the ABC parts for the ST/46 and that is all I used. The Rustler's do not run well on Castor fuels.
Ed

[minnesotamodeler]

128 oz. in a gallon...to increase 1%, add 1.28 oz.  Doc, your 4 oz. amounted to an additional 3.5% or so.  Doesn't seem like too much to me; I've added much more than that before. 

This is approximate, rule-of-thumb...don't jump on me for not being precisely accurate.

[john e. holliday]

Frank,  I am using Excaliber Fuel that I picked up while at VSC.  Leroy Black is listed as a member on this forum.  Try him,  DOC Holliday

[Pinecone]

http://www.morganfuel.com/omega_blends.htm

Omega is 75% synthetic/25% castor.

And I have heard the old by weight statement for most every fuel on the market (except maybe Sig).  So I took 50 ml of Morgan Cool Power 30% Heli fuel (advertised at 22% oil) and evaporated off the alcohol and nitro (using heat) and ended up with 11 ml of oil left.  EXACTLY 22% oil by VOLUME.

I would bet that the basis of this rumor is that most places probably mix by weight, but have converted the proper volume to a weight using the density.  It is much easier to measure large amounts accurately by weight versus actually measuring the volume.  But if you do the calculations using the density, you will get the final proporations as reported by VOLUME.

So 10% nitro (by volume), 20% castor oil (by volume) would be mixed at the weights of (for 5 gallons):

Nitro - 4.755699  pounds = 4 pounds 11.915 ounces
Castor - 8.0199335 pounds = 8 pounds 0.319 ounces
Methanol - 23.127619 pounds =23 pounds 2.042 ounces

So to mix 5 gallons accurately, you could put a 5 gallon bucket on a 50 pound capacity scale, hit Tare to 0 the scale with the bucket on it, then add 4 pounds 11.9 ounces of nitro, hit Tare, add 8 pounds 0.2 ounces of castor, hit Tare, and add 23 pounds 2 ounces of methanol mix and have 5 gallons of 10% by volume nitro and 20% by volume castor.  

For reference, this works out to 13.246% nitro by weight, 22.338% castor oil by weight, and 64.417% methanol by weight.

You can measure weight to the 1/10 ounce much easier than you can measure say 2 gallons to the accuracy of less than 1 ounce.