Flooding procedure

[JDH]

It seems that once a winter, I mess up and flood the engine and can't get it started. Engine is a O-300 A. I had pre-warmed, but probably not enough; was naturally, in a rush... Normally, when it is properly pre-warmed, It starts same as in the summer. When no pre-warming cold starting procedure gets her going just fine. But when I mess up and it is "quasi-warm" I flooded it.
What is the best starting procedure after flooding the O-300?
Thanks, JD

[Roesbery]

Have had some luck rotating the prop backwards with the Lycoming. Maybe 8 or 10 times before trying to start again. Might work with the stock engine.

[zero.one.victor]

I would pull the mixture to idle cut-off,firewall the throttle,and try to start it. When it starts,retard the throttle and advance the mixture. I believe this is similar to the "hot-start" procedure recommended for some injected engines.
You might want to crank the starter a bit with the mag switch off,to clear out the flooding. If that was successful,you might then be able to start it normally,without going thru the above drill.

Eric

[funseventy]

There is a lot of info missing to give you good advise. When you prime does it go into the intake or to all cylinders? How do you know it's flooded? Just because its dripping fuel doesn't mean the cylinders are flooded. If the engine is cold or quasi-warm the fuel will not get to the cylinders. It would rather dribble out the bottom. If you don't have the time to pre-heat properly I would give it 2 or 3 shots with the primer and try starting. If it doesn't start right away, pump the throttle a few times while the engine is turning. While its turning it will suck that fuel up into the cylinders. If it is truly flooded I would suggest, mags off, throttle full open and turn the prop backwards by hand. If you don't open the throttle the butterfly will restrict the flow enough to where you may or may not get the fuel backed out. 10 Blades is the good number. I would say more than likely the airplane was not flooded it just could not get the fuel and started dripping. Anything you tried to do to fix the flooded engine was just keeping more fuel from getting to the engine and thats why it would start.

Kelly

[N170GA]

Here's my 2 cents worth!
I fight the urge to alter my summer starting proceedure at all costs. For some reason I have the urge to add one or two extra squirts when it's cold, but have learned that to be counterproductive and illogical. If I miss the initial fire of the engine when the engine is cold (below 32F) or multiple attempts using more priming or pumping the throttle don't work...
Mixture to lean, Crack the throttle (same as for normal start) and attempt start. The first few rotations of the engine will frequently clear the condition. If the engine fires at all during this attempt, I return mixture to rich while cranking (if possible) or try again with mixture lean. In Minnesota if that fails you roll her back in the hanger and heat her up again. I have had much better luck this year with strictly following this procedure. Oh yeah...one other thing...I leave for the hanger a half hour earlier than I use to, so I don't have to skimp on the pre-heat.

Neil

[GAHorn]

C145/O300 engines usually are primed at the left intake manifold. This means that only half the engine is getting the enriched fuel.
When it's cold, these engines don't like it!
In temps below freezing it sometimes takes up to SIX full priming shots, and then let it sit 1/2 minute to let that vaporize a little. Then load the primer with another full charge of fuel. Crack the throttle 1/4" and crank! When it fires, push that loaded primer in and recharge it quickly preparatory to another push!
This system works for me when it's below freezing. Otherwise, the engine is a real beast.
In warmer temps (above freezing/below 60F) I use 3 shots of prime, and that's all it takes, along with 1/4" of open throttle.
I use no prime above 60F, only a few strokes of the throttle accelerator pump.
In really cold temps, have a ground-handler outside looking for backfire flames. Brief him to rotate his arms wildly encouraging you to keep cranking on an engine that shows flames. And keep him armed with a fire extinguisher in case things get out of hand.
Inspect your air filter backside often in cold weather for signs of intake fires.

[6886]

That's a great procedure George. I've used it successfully on 2 170's over the years. Add to that: I give it the first 2-3 shots of prime before my ritual hand pull-thru of the prop. I pull it thru 3 or 4 blades when very cold, give it the 2-3 shots and pull it through a few more. I guess by the time I'm strapped in those seconds you wait have elapsed. Of course that's all after a pre-heat if it's below freezing. A couple more shots and 1 loaded and ready and it always starts right up and the loaded one will keep it going.

[JDH]

Thanks guys! I now know what my problem was. You see, when I do pre-heat properly, set the timer the nite before for a morning run, she'd start right up. One day, someone told me: If you properly pre-heated, do not use cold weather starting procedure, your plane doesn't know seasons, it is warm and you should start it as if it was in the summer, otherwise you will flood it. I started doing that and it would start OK. But on this day that I rushed the pre-heating, I again did not use cold starting procedure and that's where I got into trouble. After reading your posts and thinking it through again, I remembered that I did not have problems before following my buddy's recommendation. So, I've been following the cold weather procedure on initial start up when its been pre-heated and no more trouble and I have had to start her up after 4 hours on a lake on a -15ºC day and she starts right up. Thanks guys! JD