I just bought a Testor McCoy .40 RC engine of the bag.
I like the look and will not fly it, only run it on the test stand.

Thanks.

This was the McCoy Series "21" I think they called it? They came out about 1971 or '72? They were not very successful with this version. They did not sell and the company soon shut down.

Good engine though. Dykes ring made hot restarts difficult, but if you let it cool it was pretty strong for its size. Mecoa still lists parts for them. You will have to find a strap on muffler for it.

I have the same engine N.I.B. but in .20 RC size - Series 21 - mine also dykes ring. To me it's interesting because of the rather unusual shaped crankcase. Even though I've been modelling for 30 years, mine is the only one I've ever seen. Maybe they were more common here in Australia during the 70's - perhaps I lived in the wrong part of the country & missed all the action

30 years is about 5 years short. The Testors .21 was sitting in just about every hobby store in the early 70's. They were the cheapest engine in the store for their size. So when Testors decided they were not going to sell McCoy's (they didn't go under, just decided they were not going to sell flying models or accesorys), the remaining stock sold fast. Most were control line engines and usually owned by beginners. As such they soon met their demise in a crash, (thats what happened to mine). I am told they didn't last well but so what they were super cheap. There are still many around, but their value is so low nobody bothers to sell them.

My first "big" control line engine was one of these...a .29...it went into a Goldberg "Shoestring Stunter" and I still have it. ( got it for Christmas in '72 from a chain department store)

The rod is un-bushed, so you should run it on a fuel with mostly or all castor oil content. I wouldn't use more than 10% nitro either...5% should be enough...especially if you're just gonna bench run it.

My .29 ran well...but like S-P said, hot starts were difficult at best.

I resumed flying control line when I got out of the USAF in January of 1969. Got married that June and the wife joined me in the hobby. We flew McCoy .40 Redheads and K&B .35 Stallions on our control line models, then, just as the Series 21 made it into the rumor mill, we jumped into flying R/C.

I had messed with R/C a bit while in the USAF (1966), but mostly flew control line because of the financial situation that being in the military brought back then.

I looked at a few Series 21 R/C engines, but never bought one. I was an ardent OS fan back then.


Ed Cregger

Thanks.

I really like the little diffrent tings, I have newer seen on here in Sweden.
My dad flew alot C/L in the 1950-60 and used McCoy's only.
He still has all of them in a box in the garage.

Thanks.

I do remember reading an article in one of the US model mags where McCoy and K&B were wheeling and dealing so that McCoy could use some internal parts from a K&B .40 in the McCoy Series 21 engine. Perhaps the dykes ring and piston?


Ed Cregger

Hello all. I have a McCoy .29 that i got for dirt cheap at an estate sale about 3 or so years ago. So it sat around until today when i was like what the heck i'll see if it'll fire, ( all you old timer die hard control liners better not read this or had better take your heart meds ) so i replaced the glow plug with a new McCoy and flooded the engine with ( insert pills in mouth now) 20% traxxas nitro and cranked it over by hand to un gum it, then i flooded the heck out of it again and put my glow plug iginitor on the plug and cranked her over and after about half an our it started to backfire then about ten minutes later it fired up and ran real smooth and sounded pretty good for being so rich/on the verge of exploding due to the high nitro content. Okay so after that long winded story of how not to treat a control line engine what i really need to know is the proper nitro % to run in it is and where do i find parts like head gaskets,head bolts,and the whole needle valve assembly so i can put my O.S. .15 back together.

20% nirro and 20% mix of castor and synthetic should be good. It ran real good on Missle mist which I think was 25% nitro and 18% castor oil.