Engine Fuel

Welcome to CEF

Assuming you are here because you have a Cox or two to run

You are looking for 15% to 35% Nitro fuel with a fairly heavy OIL package in the 22% to 25% range --either all Castor oil or a blend that has more castor than synthetic

If you prefer to just buy small qty until you really want to play small engine YOU CAN go locally and usually find most hobby shops carry Racing fuel for RC cars--usually a metal Gallon can for under $20

But Beware! These do have some impressive Nitro content and are on the lower cost side...Problem is-- RC nitro cars do not need high oil contents so most will be something like 35% Nitro but 11%~17% oil, mostly all synthetic.

Actually these are a good buy and it is easy to increase the oil % by adding Castor Oils you can buy locally or on line from companies like Sig

Locally, castor oil is a tad pricey because it is sold for medicinal purposes in small quantities 4 to 8 oz at the pharmacies. This is OK to use to add to low oil fuels

Here at CEF, are all kinds of on line calculators to tell you how much of this or that to add to fuel to result in any desired blend

Beware --using fuels in small engines has various religious zealots with very strong opinions

Just know this-- Cox small engines have a ball joint connecting the connecting rod to the piston and a small diameter hole connecting to the crankshaft pin. Castor oils have very desirable characteristics in how they behave in any high temp high pressure areas of a small engine. They also do not fully burn off in combustion cycle and this fosters some heat reduction as the unburnt oil is exhausted (sliming the hell out of your model) shedding any excess heat

A cox small engine can run on low (5%~15%) Nitro fuel, but life is much easier from a starting and adjusting point of view with 25% to 40% Nitro methane a very good ignition starter in Glow plug engines.

Again a big Texas welcome to CEF