Hand propping a fuel injected 320 - possible?

Doug · #1 09-06-2009, 04:40 PM

Folks,

I am considering converting my O-320 to an IO-320 with the Precision system and had a thought about hand starting - perhaps it is not possible to swing the prop for a start like one can with a carby.

I expect the most likely reason to swing the prop is a flat battery - in which case priming would not be possible so my gut feeling is that it would be next to impossible to make an engine start under these circumstances.

What is the general view?

We have many very isolated airfields in this country and being stranded can be a major risk.

Doug Gray

Mel · #2 09-06-2009, 04:48 PM

I have "propped" many fuel injected engines. Some are easy, some are not. Every engine is different.

As you said, priming can be a problem. However, unless the battery is completely dead there is usually enough to prime.

sandifer · #3 09-06-2009, 05:12 PM

If you're by yourself, you might have trouble getting back to the cockpit to push in the mixture before the engine quits. But I have limited experience with injected Lycomings. Is there truly significant fire risk in starting with mixture rich? I follow the manual for my IO-360, but once forgot to pull the mixture to idle cut-off for a hot start, and it started immediately, without the normal few blades of cranking.

pierre smith · #4 09-07-2009, 05:22 AM

...I have propped IO-520's in Cessna Agwagons in my younger days and as Mel pointed out, they're all slightly different. I'd prime the engine for a few seconds with the mixture rich, mags on, then run around and prop it. Cold, they started easily....hot, almost impossible and I suspect the Lyc would be much the same.

Experiment at home and see what it takes so you won't have to learn when you're stranded someplace. I have a three-bladed Catto on my -6A and I tried propping it once...scary...since the next blade is too close for comfort. For this reason alone, I'd have a two-blade in the event it needs propping in a remote area.

Regards,