Unflood engine

[DannyDot]

OK it is summer now and recovering from a flooded engine is with us.

I am looking for ideas. With a starter motor, turning it over with full throttle and pulling it back as soon as it starts is a good way. But how about without a starter motor. Does opening the throttle and turning over backwards work? How about ignition off, open throttle and turn it over forwards a few time?

[flylo]

Re: Unflood engine

I just open the throttle & back blade it. When I shut it down I shut off the fuel & run the carb dry. Works for me. I like your web site!

[DannyDot]

Re: Unflood engine

I just open the throttle & back blade it. When I shut it down I shut off the fuel & run the carb dry. Works for me. I like your web site!

So you use your fuel shut off to kill the engine? This sounds like a good way to avoid flooding the engine next time it.

On back blading. How many time backwards before you attempt to start it again?

[btbell]

Re: Unflood engine

Danny,

I usually pull it through backwards about 10 blades or so and it will start on the next blade. Your engine may differ a bit so just pick a number to start with.

Good luck,
Brian

[flylo]

Re: Unflood engine

10 or 12 blades normally works. Shutting off the fuel really helps when you just land for fuel & the engine is still hot when you restart. You just have to find what works for your plane.

[flyguy]

Re: Unflood engine

One additional thing. If you think you have a rich condition as in a warm engine after you stop for fuel I think cracking the throttle provides two advantages. First a cracked throttle gives a leaner mixture than a completely closed one. In addition you may avoid the single pop and then dead response because it is flooded again. Usually the single pop with the throttle cracked will develope enough power to get to the next cylinder which has a leaner mixture because the throttle is cracked and will fire also. This works well for me after I have "cleared" a flooded engine.

This has worked on 3 different continentals for me.

Just something to try under those conditions.

DC

[taylorcraftbc65]

Re: Unflood engine

Danny,
I start the first time with a cracked throttle. If that floods the engine, I backblade it 7 or 8 blades, and that does the trick. Brie

[n6346m]

Re: Unflood engine

The idle mixture screw (the big thumbscrew at the back of the carburetor) on a stromberg carb is an air screw. Perhaps your idle mixture is too rich. Try unscrewing it (CCW) one quarter to one half turn and see if that helps. Also when shutting down I let the engine idle at 700 to 750 RPM and leave the throttle alone to start the engine. This is my third C-65 powered airplane and I finally discovered that for me "cracking the throttle" was never an exact science. It seemed that every time I cracked the throttle it was always different. There is usually a certain amount of "slop" in the cable or linkage or even the carb butterfly or my own guess as to how much to crack it, that I could not get repeatability, so I have been using this technique for the last ten years and it has worked well for me. Yes, I have accidently bumped it over the years and had to search for that sweet spot. I also know where that starting range is on my throttle quadrant (L-2) so I don't wind up with a high RPM surprise if the throttle has been messed with. I always start with the fuel valve closed. Unless you have one of those rare Strombergs that doesn't drip, your float bowl is overflowing and raw gas is pouring out your air intake, affecting your mixture. I have never been successful at starting an engine when gas was dripping out of the carb. Do whatever works for you, I just thought I would pass this along.
Bob

[M Towsley]

Re: Unflood engine

Danny,

I learned this the hard way. At shutdown, idle about 800 and then shut off your mags. Briskly advance the throttle to full throttle. This is the 'book' way of shutdown. Upon startup, crack the throttle a little. Remember, when the throttle is closed it will pull in fuel every time the prop makes a revolution. If you are shutting it down at idle, this is part of the problem. If flooded, I found out that opening the throttle fully and rotating the prop backward several times helped clear it out. Don't ask me why, as some will argue it doesn't do anything, but it worked for my BC-12D I had. I follow the above and never had a hot start problem again. Opening the throttle fully after shutdown accomplishes two things, clearing the carb and cooling the cylinders to prevent the engine from detonating from any hot carbon deposits, etc.

[flyguy]

Re: Unflood engine

"The idle mixture screw (the big thumbscrew at the back of the carburetor) on a stromberg carb is an air screw. Perhaps your idle mixture is too rich. Try unscrewing it (CCW) one quarter to one half turn and see if that helps."

Man I hate doing this, but 144 people have read this and some may not be knowledgeable or experienced enough to realize that that this is not true.

All the drawings I have of strombergs indicate that it is a fuel metering adjustment screw with standard right-hand threads so turning it counter- clockwise, that is backing it out, will make the mixture richer, just like on other carburetors.
It has been a while since I adjusted one, but my personal experience confirms that it does in fact work that way.

If I'm wrong on this, someone correct me.
Darryl

[Len Petterson]

Re: Unflood engine

FULL THROTTLEL WITH MAGS OFF, NEVER! IF THE MAGS SWITCH FAILED . AND SHE STARTS WITH FULL POWER, EVEN FOR A SHORT TIME!
NO THANKS IT COULD TAKE YOUR HAND OFF OR RUN YOU OVER.
LEN
MIKE H DO YOU HAVE ANYTHING TO ADD?

[mhorowit]

Re: Unflood engine

MIKE H DO YOU HAVE ANYTHING TO ADD?

Chocks and tie downs MikeH

[VictorBravo]

Re: Unflood engine

Please forgive the hijack...

Danny, the guy from the Twilight Zone was not Ron Seward, it was Rod Serling. I can't imagine any child of the Cold War not knowing that

Your website does indeed have an interesting story to tell, but IMHO your story should be told with better spelling, grammar, and punctuation.

The better it is written, the more effect it will have... because the way it is now someone can (wrongfully) take a shot at your entire credibility by pointing out that the quality of your writing does not seem commensurate with the level of professional achievements you have reached in your life thus far. if I were a NASA lawyer that's the first tactic I'd be using to take you out in terms of PR.

If the website content was formatted differently, written better, and had more data, perhaps you can get NASA to raise their offer to a higher number!

[DannyDot]

Re: Unflood engine

snip
Also when shutting down I let the engine idle at 700 to 750 RPM and leave the throttle alone to start the engine. This is my third C-65 powered airplane and I finally discovered that for me "cracking the throttle" was never an exact science.
snip
Bob

I really like this idea for cracking the throttle. Set the RPM, tighten the throttle lock, then shut down.

Danny Deger

[Pearson]

Re: Unflood engine

I agree with Darryl!!! Screw the thumbscrew IN to lean the mixture, OUT to enrichen. A 1/4 turn makes a difference.

I also agree with Len Petterson. I personally would never prop my engine with the throttle wide open unless the tail was tied down.

The few times I have flooded my engine,the backward propping cleared it out after 10-12 revs.

The obvious solution is to avoid flooding. How you do that varies with each aircraft. On MY airplane the technique that works for me is to shutdown with the fuel shutoff valve, open throttle as the engine dies. And I alway start with the throttle fully CLOSED. After the engine fires I have to be quick to get the the throttle to crack it so the engine keeps running.

The main thing is to be patient when you are experimenting to find what works for you. Pay attention to the OAT and whether your engine is warm or cool. The technique will vary according to those conditions. And always think SAFTEY. I like the prop from behind method with the right door opened against the cowl.