Hi Randy,

Welcome aboard and many thanks for your comments. Especially thanks for the answer to, "why bother, kerosene is cheap and available". And about torching your engine to get it going on a low ether mix. Maybe not necessary. Just use a high ether prime and a half dozen prime runs should get you into the temperature range you need for a start. I use a prime mix of 50% oil and 50% ether.

About lubricating oils.

Much of my work with engines has been 1/2A. When you think of 1/2A, I think that naturally you think of Cox engines. Cox engines, (and only a few others) are unique in that the wrist pin isn't a pin at all but a ball socket. This ball socket is, what I call "shrouded". Shrouded by the piston. Another engine that has this shrouded issue is the VA engine, both the original split case and the latter MK2, which is a true and nearly only true, 1/2A ABC engine. The VA is unique in that the wrist pin is supported by a carrier that is threaded on the outside. This is then screwed into the threaded interior of the piston. You're given shims to apply on top of the carrier to adjust the length of the overall piston/rod assembly. You can see that you can make very fine adjustments to engine timing this way. This is likely why VA did it this way as both are primarily used in contest work, free flight and combat.

So what does this have to do with castor? Cox recommends that you use only their fuel for a good reason. It's an all castor formula. And VA also insists that you use an all castor fuel.

Cool Power is known to be a good fuel but it's an all synthetic and has only 18% oil. Yet I've been running it in Norvels for many years with perfect satisfaction. Excellent power, superior throttling and never a problem with rod wear.

BUT, use Cool Power in a Cox engine or a VA and your piston pin/socket wears out pretty quick. The issue with the shrouded pin/socket is that you get very little fresh lube circulating in this area. With a conventional wrist pin arrangement, on the down stroke, crankcase pressure tends to feed a little lube into the minute clearance between the pin and the piston. You have to have SOME clearance and all you need is a tiny amount for effective lubrication. In turn, this flow of lube allows some of that to work its way into the pin/rod interface. Picture a 1/2A doing 18K and you can see that a lot of fresh, circulating oil can happen.

So castor IS a superior lubricant, in my opinion, but not just because it protects against a lean run. I will concede though, that lean run protection was needed and put to good use on early technology engines using cast iron pistons and steel sleeves. These most often had tight fits that needed to be carefully wore in. In this case, where the piston and sleeve grew at the same rate with heat, a lean run could easily damage an engine before you managed to get on the throttle to save it. ABC style engines behave differently, as we all know. Having said that, and despite *****g the needle on many an older style engine, I can't recall ever "frying" an engine.

Many times, you hear that you should set your needle a little rich to prevent damage "if you got off a little too lean". This really IS good advice for freeflight and controline but during contest work, maximum power is the norm. So you risk frying an engine if you did get off with an overlean setting because you were stuck till the tank ran dry, the timer went off, or the engine seized. In that case, the unique characteristics of castor serves us well. But what the hell, most times we DO have a throttle and can save the engine before we ever hurt it.

In my dabbling with oils and fuels, I have REALLY bashed this poor, old Norvel .15. So far, only the rod bearing surfaces have seen any wear. Wear so bad in fact, that on one run the wrist pin actually suffered galling. But the piston/cylinder assembly is just fine with good compression seal still evident. The crank to case clearances have also held up well although by now, a bit of slop had prompted me to install brass bushing.

The brand/quality/grade of castor is important. Most everyone, except me, just knew that kerosene won't blend with castor without the help of ether. Well, Klotz's Benol will,, as long as the temperatures are reasonable. Last year I decided to simplify fuel mixing by making up a no ether mix with the percentages adjusted so that adding just this much ether gave me the exact percentages I wanted in the final mix. That strategy simply worked, I had no idea that it shouldn't.

I suspect that in most cases, we don't really NEED the superior qualities of an all castor mix. Especially, I think, in modern, ABC style diesels. On the other hand, back a while I spoke with a rep from Klotz. A right nice fellow and naturally, he thinks that Klotz makes the absolute best oil in the universe. He laid claim that their all synthetic is all you need and in fact you can run oil fuel ratios as low as twenty or thirty to one. I would dearly love to be hired by Klotz to prove this. With engines provided by them, of course.

It sounds like the modified olive oil has some of the properties of castor and some of the properties of a synthetic. If that could be proved though, and if Klotz made such an animal, how hard would it be to convince enough people that olive oil,,, jeez, OLIVE OIL??? was something that they should try in their six thousand dollar dirt bike, or snow machine?

But you never know. Maybe Morgan Fuels is reading this right now and six months from now, they'll come out with a fuel that performs as well as a castor mix but with all of the desireable properties of a synthetic.