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  • May 12, 2021, 06:51:51 PM

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Author Topic: McCoy 35 rear venturi, front tear down  (Read 596 times)

Offline Scorpionjack

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McCoy 35 rear venturi, front tear down
« on: February 27, 2021, 08:16:52 PM »
I've rebuilt probably 30 McCoy 35 redheads.   First time I've seen a rear venturi McCoy Sportsman 29. I can't find anything on it.  It's cleaned and serviced. I'll run it up this spring.  Would be nice if someone knows something about it.

Online dennis lipsett

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Re: McCoy 35 rear venturi, front tear down
« Reply #1 on: February 28, 2021, 07:43:04 AM »
I've rebuilt probably 30 McCoy 35 redheads.   First time I've seen a rear venturi McCoy Sportsman 29. I can't find anything on it.  It's cleaned and serviced. I'll run it up this spring.  Would be nice if someone knows something about it.
t
The Sportsman series of motors from were at best just mild sport engines. I remember the rear venturi engine. Dick McCoy was into cars and didn't fly aircraft. I think that it was probably used in some form of car at the time. But it could easily be used in the right model aircraft. If I remember Sportsman engines were made up to about 56/7? discontinued when the redhead 19.29.35 engines came out in 57. my memory isn't the best anymore so I could be off a year.

Offline De Hill

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Re: McCoy 35 rear venturi, front tear down
« Reply #2 on: February 28, 2021, 01:34:40 PM »
The McCoy Sportsman engines were all rear venturi engines. They were made from 1948 to 1949. Some were Ignition, and some were glow. They were more powerful than the front rotor  McCoy "Stunt" and "Super Stunt" engines that followed them. The front rotor stunt and super stunt engines were made from 1950 -1955.

The McCoy co. bought out the Duromatic co. in 1956. The front rotor Redheads were produced from 1957 to 1966.
Dick McCoy made the first Red Head prototypes. The Red Head McCoys and the Johnson series of engines both used sintered iron pistons. The McCoys ran well, but wore out quicker than the Johnsons. The McCoys MAY have had a cylinder made of softer metal that made the McCoys wear out sooner.

The McCoy series 21 series followed the redheads. They were ringed and overweight, but ran well . Wild Bill Netzeband designed the interiors, and an unknown artist designed the exteriors making them heavy. (but streamlined looking )
De Hill

Offline frank mccune

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Re: McCoy 35 rear venturi, front tear down
« Reply #3 on: February 28, 2021, 03:23:47 PM »
      Hello:

       I have had some of these, and they all had very low compression.  Mine had two rings that should have been replaced!

       I did get a .19 and a .29 running, but they were very low on power! I thought that they would look great on an airplane of the same vintage. I doubt if they have enough power to fly anything that would put a smile on your face.  I also had a McCoy .098 That had the same problem.

      Good luck with the engine and let us know of your progress.

       Frank

       

Offline De Hill

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Re: McCoy 35 rear venturi, front tear down
« Reply #4 on: February 28, 2021, 08:33:11 PM »
Hi Frank,

Are you talking about the Sportsman engines?
De Hill

Offline frank mccune

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Re: McCoy 35 rear venturi, front tear down
« Reply #5 on: March 01, 2021, 08:40:45 AM »
         Hello De Hill:

          I am speaking about engines that look like the engine in the first photo.  I may have these stashed these in my junk drawer.  I can not justify the expense of returning these engines to running condition.  Perhaps someday.

         Stay well,

          Frank

Offline BillP

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Re: McCoy 35 rear venturi, front tear down
« Reply #6 on: March 07, 2021, 10:20:09 AM »
I'm looking at Anderson's book and none of the McCoys of that vintage show an angled venturi. They are all facing straight back and at the top of the backplate. I had a 29 bump lug like that. It was identical to your pic but with the venturi pointing straight back. It had a single ring and ran about like a Fox 35. That would have been in the pre Superstunt era according to Anderson.
Bill P.

Offline De Hill

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Re: McCoy 35 rear venturi, front tear down
« Reply #7 on: March 07, 2021, 11:04:42 AM »
Hi Bill P,

If you will look in Tim Dannels American Model engine encyclopedia, (volume 2, on page 157) It shows a 1949 McCoy Sportsman .29 with bump lugs and an upward angled rear intake venturi.
De Hill

Offline BillP

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Re: McCoy 35 rear venturi, front tear down
« Reply #8 on: March 07, 2021, 02:49:07 PM »
Hi Bill P,

If you will look in Tim Dannels American Model engine encyclopedia, (volume 2, on page 157) It shows a 1949 McCoy Sportsman .29 with bump lugs and an upward angled rear intake venturi.

Yeah, I went on ebay after writing that note and there are several with the upward venturi.
Bill P.


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