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What is best way to start a flooded engine


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On 12/24/2013 at 9:34 AM, Bob_Belville said:

This is SOP for the IO360 which probably will work with your O360. 

 

Flood engine start procedure for the IO-360 in the M20E ·         Master switch on  ·         Throttle, prop and mixture full forward ·         Boost pump on 3 seconds, then off ·         Mixture to IDLE/CUTOFF ·         Throttle full OPEN ·         Engage the starter  ·         Slowly pull the throttle back towards idle as the engine is turning over with the starter engaged  ·         When the throttled is reduced to about ½ to ¾ towards the idle position, the engine should fire after the throttle hits the position for the perfect fuel/air mixture for starting ·         When the engine fires, smoothly increase the mixture to full rich ·         Bring the throttle back to the normal idle speed (1000-1100RPM) ·         After idling awhile, lean the mixture for smooth operation on the ground and during taxi

This has been the ONLY way I have been able to consistently start my engine after it  has ran for any period of time. Taxi from hangar to fuel pump.... need to do a flood start. Fly for 3 hours, shit down for lunch, need to do a flood start. 
I’ve seen Don Maxwells YouTube and it doesn’t work for me. 
Tried several other ways to no avail. 
I just stick with this procedure and 7-8 blades max it’s fired up. 

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On 12/24/2013 at 2:07 PM, orionflt said:

I like what bob posted except if you are flooded, you do not need to run the boost pump to pressurize the fuel system, all you are doing at that point is dumping excess fuel overboard.

FWIW, my AME told me you’re using the boost pump to “make sure you’re flooded”. Sounds crazy, but his theory is that you now know what you’re dealing with for certain, and won’t do any damage.

 

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On 5/21/2020 at 7:45 PM, Matt Ward said:

Sorry to dig up a seven year old thread, but, what is the answer to this question? The reason I ask is this:1966 M20e, newly OH fuel pump. Cold crank this morning (Denver, 40 degrees) was fine. Ten minutes of taxi, shut down, check fuel pump for leak out of the tattle tale. 3-5 minutes of shutdown. Go to restart and decide to use hot start, no luck. Then decide to use flooded. No luck. Tried 4 or 5 times I think with the flooded start procedure. But I did manage to flood it! I only know that because I got out to check the sniffle and saw a pile of avgas on the ground. How would I have known from in the cockpit? Would it be because the hot start wouldn’t get a cough? Fuel pressure above zero? Any clues to help me know which starting technique to use would be greatly appreciated!

3 to 5 minutes of running is not a hot start but the procedure may work. A hot start by my definition means the engine compartment is heat soaked. Under these circumstances the injector lines which are on the top of the engine, absorb heat coming off the cylinders immediately after shutdown. The now stagnant fuel in the lines quickly reaches its boiling point and expands into the intake manifold. I’m am sure that you’ve heard the sound of hissing and burbling from the cowl after shutdown. That is fuel being squeezed through the injector into the intake manifold. In effect, this pre-primes the engine for the next start and is the reason why priming is not part of the hot start procedure. An engine that has been run for 5 minutes is not likely to boil fuel into the intake manifold so a hot start technique is sub-optimal. An engine that has been run for 5 minutes is not flooded so the flooded start technique is also sub-optimal. An engine that’s been running for 5 minutes is not the same as an engine that has not been run in days. In such a case, a quick primer shot (1-2secs) should be enough for a restart. 

Edited by Shadrach
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On 5/21/2020 at 9:22 PM, mike20papa said:

If you have not flown in months - there's a chance no fuel in the carb bowl.  turn the master on, turn the aux. fuel pump on till you see a few pounds psi.  turn it off.  pump the throttle (acc. pump) about 4 full strokes.  mixture rich, crack the throttle, make the left mag hot then hit the starter.  good luck.

Also, not a bad idea to pull the top plugs, spin the engine and pre-oil the motor. especially when it's been sitting for a while.

No carb bowl on the Bendix RSA fuel injection system.;)

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On 5/21/2020 at 10:08 PM, Tahir K said:


Would you say it's a bad idea to just always go straight for the flooded start to not have to deal with a failed hot start/dead battery?

I would say that’s bad SOP. If your plane is hard to hot start, something is either wrong with the airplane or the procedure.  I have met several people who have had a hard time hot starting their mooneys. One case was cured by rebuilding the fuel servo. The other two were entirely based on poor operating technique.

Edited by Shadrach
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Gents,

use some caution...

The thread is aged...

The new guy re-livened it... and has the same question regarding his engine...

The technique And hardware may be different... but the logic is all the same...
 

 

It helps to be forgiving...

Some of the most helpful people around, are burdened with harsh writing skills...   :)
 

PP thoughts only, 

Best regards,

-a-

 

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5 hours ago, mike20papa said:

The guy's question concerned starting a B model. Also it was NOT a hot start question.  The B model with an O-360 - has no fuel servo, cause it has a carburetor.   You are complicating things, here.

This is a seven year old thread. The OP@rockydoc has not visited this site  since 2015. The recent resurrection of this thread was by a gentleman asking how to start a 66 E model.

Edited by Shadrach
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On 5/21/2020 at 6:45 PM, Matt Ward said:

Sorry to dig up a seven year old thread, but, what is the answer to this question? The reason I ask is this:1966 M20e, newly OH fuel pump. Cold crank this morning (Denver, 40 degrees) was fine. Ten minutes of taxi, shut down, check fuel pump for leak out of the tattle tale. 3-5 minutes of shutdown. Go to restart and decide to use hot start, no luck. Then decide to use flooded. No luck. Tried 4 or 5 times I think with the flooded start procedure. But I did manage to flood it! I only know that because I got out to check the sniffle and saw a pile of avgas on the ground. How would I have known from in the cockpit? Would it be because the hot start wouldn’t get a cough? Fuel pressure above zero? Any clues to help me know which starting technique to use would be greatly appreciated!

You know it is flooded when it pops and you advance the mixture and it dies.

 

Hot start:

Shut down via mixture at 1100 RPM.

For start don't touch anything.  Don't use the elec fuel pump

Crank it should pop.   Advance mixture.

It was running when you turned it off.   It will run again when you spin the prop.

 

Flooded:

Open throttle fully.   Mixture off.

Crank till pops

Do the two handed dance of pulling the throttle back and advancing the mixture to keep the engine running.

Flooded starts have the ability to blow up your exhaust system.   I would not recommend doing it very often.

 

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In my experience a lot of students and even seasoned pilots don't understand what really constitutes the hot start vs normal or flooded. This is part of the reason for all the confusion, just something to keep in mind. Note the procedures, but also focus on the feedback from the engine as you apply these procedures. You will have it figured out in a few flights. 

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10 hours ago, Yetti said:

Flooded starts have the ability to blow up your exhaust system.   I would not recommend doing it very often

AFAIK, only issue with failed hot start is dead battery & hot ignition, with flooded start it could go really very bad if you don’t cut fuel or open that throttle wide open when it blows up 

Edited by Ibra
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2 hours ago, Ibra said:

AFAIK, only issue with failed hot start is dead battery & hot ignition, with flooded start it could go really very bad if you don’t cut fuel or open that throttle wide open when it blows up 

I was kind of surprised of the number of people saying just flood it.  Do you really want to be sitting over a pool of AVGAS when the thing actually fires off when most exhausts point at the ground.

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2 hours ago, Ibra said:

AFAIK, only issue with failed hot start is dead battery & hot ignition, with flooded start it could go really very bad if you don’t cut fuel or open that throttle wide open when it blows up 

 

13 hours ago, Yetti said:

You know it is flooded when it pops and you advance the mixture and it dies.

 

Hot start:

Shut down via mixture at 1100 RPM.

For start don't touch anything.  Don't use the elec fuel pump

Crank it should pop.   Advance mixture.

It was running when you turned it off.   It will run again when you spin the prop.

 

Flooded:

Open throttle fully.   Mixture off.

Crank till pops

Do the two handed dance of pulling the throttle back and advancing the mixture to keep the engine running.

Flooded starts have the ability to blow up your exhaust system.   I would not recommend doing it very often.

 

I have see multiple airplanes of all makes and models catch fire from flooded engine starts. We almost lost a beautiful Stearman on our field. He was smart enough to keep cranking inspire of the flames and the running engine smothered the fire. Still caused minor damage. My dad lightly melted the ram or cable on our F model back in the 80s because of a fire caused by a flooded engine. 

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The last time two chaps turned up to club house asking for help after 30min of trying to hand start their wood & fabric, someone asked them to check if they still have enough fuel in the tanks for their trip? or if all of it is on the ground ! there is no battery to flatten or starter to burn in that type, so going for a quick hot start first time would have done the job in that specific aircraft...

With starters & fuel injection, I am not sure how bad it can go with a very flooded engines? but if it bangs every time it is not healthy: if one can’t afford few attempts with minimal priming they may need to get new battery, new technique or fix something in the fuel system 

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On 5/23/2020 at 11:35 AM, Shadrach said:

3 to 5 minutes of running is not a hot start but the procedure may work. A hot start by my definition means the engine compartment is heat soaked. Under these circumstances the injector lines which are on the top of the engine, absorb heat coming off the cylinders immediately after shutdown. The now stagnant fuel in the lines quickly reaches its boiling point and expands into the intake manifold. I’m am sure that you’ve heard the sound of hissing and burbling from the cowl after shutdown. That is fuel being squeezed through the injector into the intake manifold. In effect, this pre-primes the engine for the next start and is the reason why priming is not part of the hot start procedure. An engine that has been run for 5 minutes is not likely to boil fuel into the intake manifold so a hot start technique is sub-optimal. An engine that has been run for 5 minutes is not flooded so the flooded start technique is also sub-optimal. An engine that’s been running for 5 minutes is not the same as an engine that has not been run in days. In such a case, a quick primer shot (1-2secs) should be enough for a restart. 

Thanks a lot.  I just flew my M20E from CO and GA this weekend and have had a few opportunities to practice this.  It's good advice.  One thing I'll add is that I'm still trying to get the feel of when to release the key from the Start position.  That seems to be a very important part of this timing - hold it over too long, no start.  Let it go when the engine starts to cough, much better.  I'm supposing it has to do with the shower of sparks system but I'm not certain of that.  I do know that, unlike other planes I've flown, there is no click if you pull the prop through by hand.  That was always an old trick I used with other planes to confirm the mag was functional (maybe not a good trick!) but on the Mooney you don't get it.  I'm guessing that's because of the shower of sparks. 

Thanks again everybody!

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4 hours ago, Matt Ward said:

Thanks a lot.  I just flew my M20E from CO and GA this weekend and have had a few opportunities to practice this.  It's good advice.  One thing I'll add is that I'm still trying to get the feel of when to release the key from the Start position.  That seems to be a very important part of this timing - hold it over too long, no start.  Let it go when the engine starts to cough, much better.  I'm supposing it has to do with the shower of sparks system but I'm not certain of that.  I do know that, unlike other planes I've flown, there is no click if you pull the prop through by hand.  That was always an old trick I used with other planes to confirm the mag was functional (maybe not a good trick!) but on the Mooney you don't get it.  I'm guessing that's because of the shower of sparks. 

Thanks again everybody!

Well be careful here with the switch... when the switch is engaged to “start” and the engine is turning over, your right mag is grounded to prevent backfire at 20 or 25 tdc.  Your left mag and sos are on their 0 degrees tdc timing to make a clean start. So it only starts on the left mag.  When you release the key to the both position, both mags are firing.

If the airplane turns over ok but starts when the key is released, it can be telling you there’s an issue with the sos or left mag.  Sometimes it will even start as you let go and the right mag fires. Of course, yeah, when it fires, you can let go the starter, just keep in mind, what’s happening with the sos and mags as you hit the starter.

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On 5/26/2020 at 9:45 AM, Matt Ward said:

Thanks a lot.  I just flew my M20E from CO and GA this weekend and have had a few opportunities to practice this.  It's good advice.  One thing I'll add is that I'm still trying to get the feel of when to release the key from the Start position.  That seems to be a very important part of this timing - hold it over too long, no start.  Let it go when the engine starts to cough, much better.  I'm supposing it has to do with the shower of sparks system but I'm not certain of that.  I do know that, unlike other planes I've flown, there is no click if you pull the prop through by hand.  That was always an old trick I used with other planes to confirm the mag was functional (maybe not a good trick!) but on the Mooney you don't get it.  I'm guessing that's because of the shower of sparks. 

Thanks again everybody!

To build on the comments of @Ragsf15e , SOS does not “click” when turning by hand like an impulse coupling. That being said, your post reads like your SOS is not working properly. Engine should fire with key in start position. Firing when the key is released to both is a symptom of the retard breaker not functioning. Could be the switch or anything downstream from there. Be careful. Starting an engine with the mags firing at 20° or 25° BTDC is a recipe for destroying the sheer pin. Not expensive but a PITA to get to. Will absolutely strand you if no services nearby when it fails. Hand proping is daunting enough with SOS and a second person in the cockpit. Dead in the water when alone with a dead starter and a dead SOS.
 

A little light reading...

http://donmaxwell.com/shower-of-sparks/

Edited by Shadrach
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