hi out there I have been having a problem starting my J 3 cub!!! It took 15- 20 times of swinging the prop through. once it was running it runs great.
hi out there I have been having a problem starting my J 3 cub!!! It took 15- 20 times of swinging the prop through. once it was running it runs great.
Are you priming the engine before you start swinging the prop. My a-65 starts on the first swing of the prop. I give it three squirts of the primer. Then pump the throttle three times to let the accelerator pump pump three times. I then keep the mags off and pull the prop through three times. Make the mags hot and she fires right up.
Tony
My J3
My J3 with a C90 starts on the first pull most times from cold, and usually on the 2nd when it has been running and if warm.
Heres my way.
First and above all tie the tail down, and put chocks in front of the wheels. Starting an unsecured plane is nuts. And even with an actual pilot inside, I'd want a tie down andor chocks. Now if you don't have a tie down, chocks are even more important, but a plane can jump chocks if the throttle is open wide.
Next, make sure mags are off, but don't take this for granted, stay out of the prop arc just in case.
Crack the throttle the smallest amount possible, just off closed.
Mine has a primer and I usually use 2 strokes, and remember to let it fill after you pull it out before pushing back in or you don't get the fuel.
2 should be enough. My Stromberg does not have an accelerator pump.
Then maybe try one pull with the mags off to pull fuel into the cylinders.
Then mags on, start close, and as you pull down step back and to the outside.
Carefull, it can kick back and grab a finger.
If it starts it should idle perhaps 600-700 rpm, just trying to move but not quite.
Give it a moment at fast idle and then close the throttle before CAREFULLY removing tail tie down and chocks, with the last chock being in the rt main wheel.
If it won't fire after several pulls, I would experiment with amount of prime. No fire at all probably means no fuel or not enough.
Try a lot of fuel, then pull prop through 2 times mags off and then mags hot and pull.
If you see fuel dripping from carb you are way too rich. In that case you can let it sit a few minutes or turn mags off and turn prop a few times to clear.
Then mags back on to start.
When hot after running I use only one prime or no prime at all.
Seems to me it is more likely to kick back when it is flooded and just cleaning that excess out, so be carefull.
Your carb may not be set right, the idle mixture and speed. Are you using av gas or some substitute? I use 100 ll and it seems to start well.
Last edited by Bill Greenwood; 06-11-2015 at 09:02 AM.
Several good ideas posted. I had Champ with an A65. Prime, etc. as Bill indicated. When cold I usually pull the prop through four revs "with the mags off". Then turn the mags on and leave the throttle at idle, generally stand behind the prop and one or two swings will get it going. Seems to me you should hit the compression on about the "two 0 clock' position from the rear or "ten O clock" from the front which indicates the prop is on right. If you do it from the front beware of the giant meat cleaver (prop) and stand away after the swing. Pumping the throttle only works if you have an accelerator pump. If a Stromberg carb, pumping doesn't help. One other thought: starting depends also depends on the magnetos and timing, etc. I happened to have dual impulse Slicks which worked well.
If God had intended man to fly He would have given us more money!
All the A-65's I've ever flown, I never bothered with the primer in warm weather. No accelerator pump on Stromberg carbs as mentioned. In warm weather, throttle closed, three pulls on the prop to suck some fuel in, mags hot and she goes.Originally Posted by 1600vw
I would love to help you but you don't give us any real information to help you.
What kind of Mags do you have, what carb is on the plane, is the prop indexed correctly and what starting technique are you using, like prime or no prime, do you pull the prop through before or after priming?
It would have helped, ACEFLYER2, if you'd given us a bit more information, like what you have bolted in between the firewall and the prop. If you're going to hand prop alone, and have long arms, all the safety steps that Bill mentions above are a good idea, but not always available. That's why I set up the engine with priming etc. similar to those above, then when the mags are hot (if you don't have an impulse coupling on at least one mag, forget it), I place my left foot in front of the tire, like a chock, and hold the front wing strut firmly with my left hand, then use my right foot to steady myself and my right hand to swing the prop. If the throttle is a little too advanced, the plane isn't going anywhere with your foot there. If you lose your balance and fall down, you won't end up in the prop, as long as you don't let go of the strut. Dick Wagner taught me this technique when checking me out in his Little Myrt and I've used it ever since.
If you do have one of those nightmare scenarios where your plane gets loose with the throttle open, don't grab a wing strut, jump on the horizontal tail and push or pull the rudder to direct the plane into the side of a hangar, a fence, an SUV, or at least away from people.
I installed this to my tailwheel airplane.
http://www.bowersflybaby.com/tech/tailhook.html
Tony
I find it works well to first just hand prop and let the engine bounce thru compression with closed-throttle-switch-off-mixture-rich to "juice" up the engine, maybe using a little prime only for a cold engine that has been sitting. I then hand prop my J-4A C-85 again on a completely closed throttle. The advantage of closed throttle is you get a momentary vacuum in the intake manifold which will help flash any liquid into vapor.
I think many try to start with too many shots of prime and too much "throttle crack".
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