The right fuel...AGAIN!

I'm SURE this topic has came up more times than most of us can remember...but that's the problem...I can't remember what the answer was!

OK...I just bought the McCoy .19 RH LB engine I was wanting. Now I just might want to re-live my childhood and put it in the air. My local fuel supplier (Ritches Brew) makes 29% castor fuel in FAI (0%), 5%, 10% and 15% nitro. I am thinking an OS A3 plug would be good in the engine...but how much nitro is good to use? Suggestions for other plugs, if the A3 isn't a good choice, and nitro % are more than welcome!

Based on what I have read on this forum and dozens of threads and
if that engine were mine I would go with the 29% castor and 5% nitro.
The OS plug A3 should be okay too.

I love Ritch's fuel. I didn't know they made an all castor. Wonder if a LHS will order me some..

I've put many happy miles on McCoy 19's with Sig Champion 10% nitro, 50/50 20% oil. Others will say run more oil, and/or run all castor.

My version of the subject line (INSTEAD OF THAT VERY STUPID SHORT limit imposed by the forum software):

RE: The right fuel... "wasn't all this somewhere in the ARCHIVES?"

Jim Thomerson wrote:

>I've put many happy miles on McCoy 19's with Sig Champion 10% nitro, 50/50
>20% oil. Others will say run more oil, and/or run all castor.
>
In retrospect, it now seems as if the Testors 19's somehow weren't quite as badly affected by the total lack of QC in assembly. For instance, fewer 19's as a percentage of total production of that size seemingly wouldn't run at all. My own personal experience with them was that they were more likely to stand up to the ordinary mistakes of beginners, with an occasional hot run less likely to destroy them.

Generally, smaller displacement engines should get fuels with lower proportions of oil and slightly higher percentages of Nitromethane.

That said, all iron piston/steel cylinder engines present their own distinct operational requirements. I wouldn't use less than 24% oil by volume, nor would more than 15% Nitro be a good idea, but 10% will be better for a 19 than 5%. My own engines have responded well to fuel mixes with some synthetic oil included. I don't see any need at all to insist on fuels with nothing but castor for oil (but at least half of the oil should be castor).
>

.

Kiwi

>My version of the subject line (INSTEAD OF THAT VERY STUPID
>SHORT limit imposed by the forum software):
>
>RE: The right fuel... "wasn't all this somewhere in the
>ARCHIVES?"

Gene, you used the correct noun, just the wrong adjective. It is indeed a subject line, and not intended for the whole text.

As to "Wasn't all this somewhere in the ARCHIVES?" well, why not do a search? If it is in the archives, then you will find it.

But, back to your original statement, these limits are set for a reason. And no matter how long we allow them to be, someone will want to exceed them. So, should we keep the subject line as-is by setting reasonable limits, or shall we expand it and let people put the whole content of their post up there and do away with all the rest?

Leonard,

If you take the time to look, it was Kiwi that changed the suject line, not I. I did realize when I posted my question that this topic existed in the archives...multiple times...Kiwi just 'plastered' that on my title. I guess I was just lazy. Sorry to exploit your members and clog your webpage once more.

For all that replied...I plan to use 29% castor/10% nitro Ritches Brew fuel and an OS A3 plug. I'm thinking since I live just North of Houston where there is essentially no Winter they should work just fine.

Use the 29% castor and 5 or 10% nitro and your vintage engines will love it. When I mixed my own fuel I would use 25% castor for the steel and iron engines and I still have most of them 30 years later. I have been cleaning them up and test running them and all still have great compression. It was a real pain to unstick them because of the old castor varnish but I guess that varnish was a great preservative.

Ritch's Super Stunt Fuel should work great in this engine. My memory of the McCoys is they had a tendancy to lose compression quickly, the heavy all castor oil should lessen this. From now to May 5% nitro should be enough, after that you might need 10% to regain the lost power due to the heat. If the plane comes out heavy consider going higher on the nitro.

Hi V.I.
The 29% castor will be fine. As Larry Foster, and many others have said, higher Nitro gives a cooling effect, also. I do not believe that you will have an "overcompressed" problem in the 19. 10% nitro to start would be my suggestion since I have used that in my Fierce Arrow 400 w/ RH 19. Didn't have any 15% or higher, or I would have tried it. Plenty of oil will help McCoys last longer.
BTW: several engine experts say that basically all fuel makers now use a touch of synthetic in all their fuels.
Bill <><