No-Primer Starting Advice

[6597]

A few details on the Marvel accelerator pump for starting...

Make sure the engine is turning so it sucks the fuel up the spider. If you don't then it just puddles in your airbox, not a good thing. Usually it takes a few seconds between 1 or 2 pumps and the engine catching, at least on my 0-200.

Make sure you do FULL strokes, otherwise the jet of fuel will hit the partially closed butterfly valve and, again, drip down and puddle in the airbox.

Otherwise it works pretty well. Haven't used the Lunkenheimer primer in years.

Don't ask me how I know this....

Seeing as our primer line just dribbles fuel down onto the throttle, it seems to me it would only be of use while the crank is turning.

Actually there should be an atomizer near the base of the spider that kind of 'sprays' raw fuel.
https://www.fresnoairpartsco.com/produc ... le-primer/
https://www.mcfarlaneaviation.com/products/AN800C2-MOD/

[6643]

Back when I was a student pilot, one of my instructors said to me "Why would you want to spray fuel into the engine if it's not turning over?"

[7896]

Hello,

My 120 has an O-200, pull-cable starter, and no primer. Seems everyone has a slightly different technique. Here is what works for me:

1. Throttle to Idle
2. Mixture to full Lean
3. Pull starter handle (prop now spinning)
4. Mixture to full Rich
5. Pump Throttle (~2 times)
6. Listen for Engine Start
7. If it doesn't fire after a few seconds, close throttle & mixture back to full Lean.
8. Wait 30 seconds and try again.

I've had success on some pretty cold days.

It could be your starter is not spinning the prop fast enough. If you are confident in your hand propping ability you might give that a try.

Hope you find success!

[6643]

If your impulse couplings are working, you can't turn it too slowly. OTOH, if they aren't working you probably can't turn it fast enough...