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Engine basics => Engine set up tips => Topic started by: Allen Eshleman on February 26, 2018, 06:03:36 PM
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My brother has just installed a Testors Series McCoy 40 in an old Nobler of mine. So far we have not been able to get it started. It is a hand me down. It does have compression. The spraybar is in correctly.
So far we have only tried to start it with the motor in the upside down position. Does this motor start better in the upright position. This will be for Sport flying.
Thanks for any help.
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Hey Allen, I assume you are talking about a series 21, the squarish engine that kinda looks like a baby impact gun, with a black head, do you know it's history. Make sure the ring isn't stuck and the other usual things is the needle valve plugged, glow plug etc. Once you get them going and the ring reseats a little bit, it will start much easier as the compression goes up. Goodluck T J
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If you have not tried to start the engine before, by all means turn it over. Figure out needle setting and such and then try upright again. You will probably find that some days it will start on the wheels and then some days it won't, especially on the first cold start of the day.
Type at you later,
Dan McEntee
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These are normally a good starter and runner. As said already turn it over at least until you get it going well for you and understand it better. It has a Dykes ring which could be stuck with old castor oil. They sometimes don't feel like they have tons of compression dry but shoot some fuel and a good battery to it and it will wake right up. Open the needle about four turns and give it a good prime in the exhaust and down the venturi. Once you get it freed up and close on the needle setting then a good choke and maybe just a tiny squirt in the exhaust-port closed- with get you going without turning the plane over. Actually in the 'old days' most guys turned them over anyway to insure good starts. These are great engines. Use at least 25% oil and a 50/50 castor/Klotz mix if the motor is fairly new. Pure castor if it's high milage.
Dave
A couple others thing to add; If it has the old Testers, McCoy or Fox plug in it-replace it with something decent. Also you might check to see if all the head and backplate bolts are snug. The paper gaskets can dry out and shrink or compress and leak.
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Thanks to all for the tips and explanations. My brother was given two of these motors and had to supply a venturi for one (I think) and various parts of the NVA's for both. They just sat in his hanger. I have this old Nobler from which I just robbed an OS 40 FP. The Nobler is more of a fun plane, a test bed, for engines. I can't wait for better weather. We should have it in a month or so, here in Pennsylvania. Then we will turn it over, fuel it up and see what we get. I can hardly wait. Maybe we will have something that can get me into some serious stunt practice.
I forgot to mention. The fuel tank had a leak in it. That has been repaired. I plan to report, when we get the chance to get it going.
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Where are you at in PA. I am western PA. I have many of the testers McCoy engines. A number of them still on planes. Loved the engine but it is heavy. No need to offer starting advice since that was covered already.
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Allen,
One item to check is the plug tightness. I recently had some trouble with a very reliable Fox 35 after changing the plug. The engine would firer but not catch. This engine would always take two pulls covering the venturi then flip 6 forward 6 backward put on the battery and spinner flip, off it would go. When the problem started to occur was after a few flights with a new plug and washer. Upon pulling the engine through compression it felt just a little soft. Checked head bolts, all tight then checked the plug and got 3/8 ish turn. Motor started fine, after the flight I checked again and got another 1/8 turn tighter.
Best, DennisT
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I am waiting for better weather and for Easter to be over. I am a pastor and this is a very busy time. We will check the fit of the glow plug. Also
David, I live in Mercersburg which is near Chambersburg and Greencastle. Not far from the Maryland line and Hagerstown, Md. We drive about two hours to get to Brodak, on Rt. 68 which is in Marlyand and West Virginia. Looks like better weather is coming and I am sure it's coming soon, regardless of the forecast. I am doing sport flying on a shoestring. The McCoy was given to us free. I started with Cox Babe Bee's and McCoy Redhead 35's and 19's 50 plus years ago. I had a wonderful running McCoy 35 on a good flying Ringmaster. Those were the days. I had a Ringmaster Junior and a Junior Flite Streak with McCoy 19's. Great stunt run on the Junior Flite Streak. In these later years I have progressed from inside loops to Figure 8's both horizontal and vertical. I've attempted triangles and a few hour glasses, the latter being far more like a vertical 8.
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Sometimes those things required a squirt off oil in the cylinder , when new . Untill the Rigs Seated .
then theyre supposed to go good. Only fault ? is weight .
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Make sure the hole in the spray bar is not clogged and dirty. Use a shot of Ronson lighter fluid in the port.
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If it gets really troublesome, put it in a test stand.
Some questions, to get us past "it doesn't start". Some of these are pretty obvious - bear with me. All are for the engine upright -- IMHO, cylinder down operation just complicates things. This list is more or less in order of importance; if you hit a snag as you go down figure you should stop and fix that problem before moving on.
- Does the glow plug light?
- What does "good compression" mean to you? You feel it when you flip it, it has good leakdown, etc.
- Do the glowplug and head seal? I dribble fuel over the glowplug & cylinder head sealing area, pull the prop over, and look for bubbles. I (and you) should probably dribble some around the stem of the plug, too, in case that's the problem.
- Does the crankcase seal? Two strokes work by compressing fuel/air mixture in the case and puffing it up into the cylinder -- if that doesn't work you'll get pops and porbles, but no sustained run
- Does fuel flow through the venturi? Try squirting fuel through with a syringe or fuel bulb.
- If you squirt fuel into the venturi, will it run out the prime? If I got this far with no joy I'd try replacing the glow plug and trying again.
I assume we'll hear from you next week -- have a good Easter.