Hot starting a Leburg VW

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Nick Allen
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Hot starting a Leburg VW

Post by Nick Allen » Fri Jul 30, 2010 9:35 am

Has anyone got a protocol for starting a VW, equipped with Leburg ignition, when the engine is warm? (The engine starts first swing when it's cold!)
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cardiffrob
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Post by cardiffrob » Fri Jul 30, 2010 3:54 pm

My (albeit limited) experience is that throttle set, ignition on....and it goes. I've not needed any choke or re-priming to get it going again. Are you having issues?
Rob Thomas
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Nick Allen
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Post by Nick Allen » Fri Jul 30, 2010 4:36 pm

Yes! I've just started flying a Jodel D9 -- first flight in it yesterday: whoo-hoo! Starting from cold, as I said, is no problem -- prime, pull through four blades, and off it goes. But yesterday, after I flew, one of the other syndicatees wanted another go, and it was a right b*gger to get going, which apparently it always is when hot. (I was not partaking of the exercise, but watched from a safe distance.) I suspect it was flooding...so maybe they are trying with too much throttle.
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Bill McCarthy
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Post by Bill McCarthy » Fri Jul 30, 2010 6:03 pm

You lucky devil - where did you get that D9 ! Give us a run down on your first flight then.

mb2
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Post by mb2 » Fri Jul 30, 2010 10:36 pm

I have a Colibri with a Leburg system fitted.
If you compressions are down, then this will cause issues when starting from hot, but be fine when cold, so it might be worth checking.
If all is OK with the above. Wind the prop backwards about 12 times, obviously with the ignition in th off position, and then attempt to start. In my experience, it's best to follow this routine as standard operating procedure when hot rather than trying a couple of prop swings, just to see if it starts. Reason being, if it fails to start, then it probably be flooded, even after a couple of swings.
Best of luck.
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Nick Allen
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Post by Nick Allen » Sat Jul 31, 2010 4:19 pm

Mark, thanks for that. I think the compressions are OK, so we'll try the winding back idea -- one of the guys has been doing that but only to salvage an already flooded engine.
Bill, a group of us at Hinton had the idea last year of buying/syndicating a single-seater, with a D9 top of the list, and after a couple of false starts, we found a decent one (we think): there are some fine photos of it in the hands of a previous owner here: http://gallery.blacknosugar.com/similar ... s=Jodel+D9
One of the syndicate has a Jodel D112, and has been kindly showing the members the ways of the bent wing. At the same time, I was doing an SEP tailwheel course on a SuperCub, which I finished a couple of weeks ago (I've been flying a tailwheel motorglider for a few years).
So Thursday, after another session in the D112, it was suggested that now was a good time for me to take the Bébé up. I had to borrow a helmet and jacket, as I wasn't expecting to do the deed that day, and had turned up in a T-shirt. Strap in, refamiliarise myself where everything is. Listen again to the counsel of those who have already flown it. A friendly swing gets the engine going. Usual checks. Chocks away! I taxi cautiously the long way round to the threshold, using the chance to get a good feel of the rudder pedals. Line up 27 -- 700plus metres of grass, wind about 20° from the right; not steady, but not gusting too much. Radio call (remembered that I'm not flying the usual aeroplane whose callsign I default to!). Deep breath. Take a guess as to how much into-wind aileron I'll need. Open throttle (and hold it firmly as I've been advised it tends to creep off). After a short run, ease the tail up, adjust swing, overcorrect, recorrect (etc.!). (Think: bloody hell, this is lively.) Luckily, soon thereafter we're airborne, and as usual it all then gets a bit easier! Let the speed build a little; ease back very gently and we're climbing well, bang on 60kts (the placarded climb speed, which the plane seemed to find on its own). I cross the far end of the runway at over 400ft, which is somewhat higher than I'm accustomed to. I spend about 40 minutes getting used to the feel of the little plane, and the sensation of being out in the open. Turns. Steep turns. A stall (which takes a long time to happen, at an infeasibly low airspeed). Can't quite get the cruise speed advertised, so will have to do some more exploration to work out how to get the wing right on the step. Pull back the power to feel the descent. I find my back is aching, then realise I'm unconsciously hunching to tuck the top of my head below the windshield. I'm loving the view; the general buffetting takes a bit of getting used to (it's quite a lively day thermally). At 1000 ft the temperature is quite tolerable, but 2000 feels chilly -- so thinking out the attire will clearly be important in future. Back to the circuit. A couple of dummy approaches to get the feel of the descent closer to the ground, and to try a go-around for size. Drop the power too low and there is a stone-like quality to the flight profile...I had been warned of this! So finally, to land: approach felt OK, until I pulled the power back bit too much, and felt the ground start to surge up. More power! Perhaps a bit too much.... Touch gently; balloon gently (so yes, it was too much power!). Correct power again, stick back a touch...and all three wheels touch the ground at approximately the same time, and pointing in the right direction. And soon thereafter we come to a graceful stop. At which event, I am both slightly surprised, but very pleased! I haven't stopped smiling since...
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Bill McCarthy
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Post by Bill McCarthy » Sat Jul 31, 2010 8:00 pm

You jammy git ! That D9 looks like the one that was in a PFA flight test report in the mag back in the mid 70s. I took a load of the magazines to sea on the sub with me at the time and I can virtually recite the report still. I've hankered after one ever since. A canopy adds a few knots to the cruise speed apparently. I think it was JC who said that the Colibri has similar performance and gave it the edge over the D9. Great picture by the way.

Jim Alex
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Post by Jim Alex » Sat Jul 31, 2010 8:50 pm

:D When I had a Leburg D9, I found that with a hot engine, touch nothing! leave the throttle in the closed position and it should start first blade. If you pump the throttle or prime by pulling it through you've had it. Best of luck!

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Mike Mold
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Post by Mike Mold » Sun Aug 01, 2010 10:23 pm

Nick, "I haven't stopped smiling since..." just about sums up the D9!
G-BGFJ 1993-2007
Mike Mold
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Watchford Farm, Devon
www.devonstrut.co.uk

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