ORIGINAL: Bob Pastorello
30. If your engine was fine yesterday, and today it's NFG, then *something* changed. Find what changed, and fix it. Don't jump to conclusions and speculate....
That is exactly what happened to my DL50 last weekend.. It's a new engine and was working perfectly the week before.
Last week, I came to the strip, put the plane out, put on the wings, charged everything up, put the canopy, fueled it up, choke, flip, flip, flip, nothing.. opened the choke, flip,flip,flip, flip,... unusual POP! from the manifold.. hmm.. it never done that before?
So, removed the spark plug, wettish.. I let it dry and start over. With choke, flip flip flip, POP! again with an unusual sound as if the timing is off.. removed the cowling, inspected everything.
I suspected the properly padded ignition, so I removed the plug, put a new plug in it outside of the engine - to see if its firing. It did seem normal. spark visible..
So here I am, with perfectly fine engine thats got fuel, oxygen and fire but no go.. now thats not possible..
needles were adjusted properly, no junk anywhere, ignition battery, switch and cables are OK...
After 5 hours of inspection, trial and fail, I came back to my first suspect: the ignition module..
Swapped out my ignition module from a frieds DL50 - no choke, flip ONCE and VRRRRRRRAMM!! Running like a clock..
Put my ignition on my friends DL50; flip, flip, flip, flip...... unusual POP!.. no go.. There it was.. a mysteriously gone bad ignition module that decided not to work properly anymore without a single reason..