After a 2 minute taxi for fuel, my F wouldn’t start

[gwav8or]

1 minute ago, MikeOH said:

I have no idea how long fuel can stay in the intake after flooding, or if there are areas that it can pool, and then 'slosh' out and drain out the sniffle when the plane is moved.  I would have thought 24 hours would be enough time for it to evaporate, but I don't really know.

Did you notice any fuel dripping AFTER your flight last night?

Use the same no prime, mixture ICO, on your next cold start.  It should be interesting to see if it starts right up, or not!

I flew for about 30 minutes.  About 45 minutes total with the engine running.  I let it sit for 20 minutes and used the same procedure to start.  No prime, Mixture ICO, throttle where Ieft it when I shut down (1000RPM).  It started after about 10 blades but ran rather rough for a bit.

Between shutdown and second start, there was zero fuel drippage.  After I put it back in the hangar after the "hot start" I cleaned up the plane (summer bugs, ugh) and there was a single drop, which I normally see after a shutdown after a flight.

[MikeOH]

Yeah, that was a hot start so not sure what to conclude from that.  I will say that after a hot start a little rough running is not uncommon for me.

Let us know how it goes on the next cold start with that technique.

[RoundTwo]

I was surprised at how little running it takes for my J to require hot start method. A trip to the pumps and it’s a hot start or no start. 

[MikeOH]

I don't look at it as a hot/cold start issue but is fuel is still hanging around from the shutdown, either in the intake runners or still in the fuel lines/injectors.  So, even a super quick taxi will leave available fuel.  So, if I just shutdown to fuel, or whatever, for <10 mins I'll leave the mixture at ICO and start cranking...bring in the mixture when the engine fires (usually just a few blades).  Performing a 'cold start' prime is near certain flooding.

If a few more blades go by without a fire, THEN I will start to SLOWLY bring in the mixture.

[Rev Rhoden]

Hello Everyone,

I'm a new Mooney M20f owner having the same issue.  It's embarrassing and frustrating sitting at the fuel bay, cranking away, lol.  It happened to me today and a friend towed me back to my tie down.  Thank you all for the comments and experiences.  I'll take any suggestions that are offered to make this restart after fueling smother.

Rev

[Ragsf15e]

11 minutes ago, Rev Rhoden said:

Hello Everyone,

I'm a new Mooney M20f owner having the same issue.  It's embarrassing and frustrating sitting at the fuel bay, cranking away, lol.  It happened to me today and a friend towed me back to my tie down.  Thank you all for the comments and experiences.  I'll take any suggestions that are offered to make this restart after fueling smother.

Rev

We’ve all probably done it at least once early in our ownership.  It happens.  Once you get a good technique, it won’t be an issue.  After a short taxi, don’t prime.  It should start right away.

I think about it as 3 possible starting points.  You can move yourself down the list, but not up:

1. Normal, cold, hasn’t been run in several hours.

2. Hot engine or has at least run in the last few hours.

3. Flooded (goal is not to get here, but occasionally you could end up here and should have a good technique to start it without lighting it on fire).

Again, you can move down the list, but not up (well actually if you try a hot start after it sat a long time and it doesn’t work, maybe you’re back at #1, so prime it without flooding).  If you need help with the technique for any of those three conditions, let us know.

[Shadrach]

23 minutes ago, Rev Rhoden said:

Hello Everyone,

I'm a new Mooney M20f owner having the same issue.  It's embarrassing and frustrating sitting at the fuel bay, cranking away, lol.  It happened to me today and a friend towed me back to my tie down.  Thank you all for the comments and experiences.  I'll take any suggestions that are offered to make this restart after fueling smother.

Rev

If it’s not firing at all, I suspect you may have a bigger issue. You didn’t say what you did in attempt to start it. To shutdown  an IO360 it should simply be pulled to idle cut off at ~900rpm. To start back up, simply turn the key and enrich the mixture with the engine fires. If that’s not working, something else is probably wrong.

[Rev Rhoden]

1 hour ago, Shadrach said:

If it’s not firing at all, I suspect you may have a bigger issue. You didn’t say what you did in attempt to start it. To shutdown  an IO360 it should simply be pulled to idle cut off at ~900rpm. To start back up, simply turn the key and enrich the mixture with the engine fires. If that’s not working, something else is probably wrong.

Thanks for the response Shadrach-- it is firing just not catching (if that makes sense).  

I turn the key and wait for the engine to catch to introduce the mixture.  The prop just turns and turns and never kicks over.  I'm afraid to drain the battery so I start from the top of introducing fuel and starting over like a cold start.  The engine has only run about 5 minutes from my tie down to the fuel bay.  

I'll keep trying different methods until I find one that works for me and my Mooney.  But it is frustrating.

[Ragsf15e]

13 minutes ago, Rev Rhoden said:

Thanks for the response Shadrach-- it is firing just not catching (if that makes sense).  

I turn the key and wait for the engine to catch to introduce the mixture.  The prop just turns and turns and never kicks over.  I'm afraid to drain the battery so I start from the top of introducing fuel and starting over like a cold start.  The engine has only run about 5 minutes from my tie down to the fuel bay.  

I'll keep trying different methods until I find one that works for me and my Mooney.  But it is frustrating.

I think @Shadrach could be right. Usually, if you crank it after say taxiing to fuel, it will fire at least through a few blades, even if it doesn’t start running. If it won’t fire at all, you may have something not perfect in your ignition system.

[Shadrach]

4 hours ago, Rev Rhoden said:

Thanks for the response Shadrach-- it is firing just not catching (if that makes sense).  

I turn the key and wait for the engine to catch to introduce the mixture.  The prop just turns and turns and never kicks over.  I'm afraid to drain the battery so I start from the top of introducing fuel and starting over like a cold start.  The engine has only run about 5 minutes from my tie down to the fuel bay.  

I'll keep trying different methods until I find one that works for me and my Mooney.  But it is frustrating.

That sounds like it is turning over but not firing (combustion).  
Do you have Shower of sparks (SOS) or an impulse coupling? 
When my ignition switch malfunctioned, I lost the SOS. For some reason the engine would start ok when cold but was next to impossible to hot start.

[Brent]

I looked this thread up today after having a bad hot start experience. I've done numerous fuel stop hot starts using the procedures cited in this thread starting with the don't-touch-anything method. Today, I flew 20 minutes to another airport, got gas and was on the ground for maybe 15 minutes and then the engine would not start. I tried all the methods, including full flood. No joy. I waited an hour and tried again; no joy. I ended up leaving the plane parked at the other airport not too far from my home base and will try again tomorrow hoping an overnight cool-down will magically cure the issue.

I'm wondering if I have another issue, but I don't know what it would be. The plane ran fine on the way in. I just had the mags IRAN refurbished a month ago and the engine has run fine since.  

[Ragsf15e]

15 hours ago, Brent said:

I looked this thread up today after having a bad hot start experience. I've done numerous fuel stop hot starts using the procedures cited in this thread starting with the don't-touch-anything method. Today, I flew 20 minutes to another airport, got gas and was on the ground for maybe 15 minutes and then the engine would not start. I tried all the methods, including full flood. No joy. I waited an hour and tried again; no joy. I ended up leaving the plane parked at the other airport not too far from my home base and will try again tomorrow hoping an overnight cool-down will magically cure the issue.

I'm wondering if I have another issue, but I don't know what it would be. The plane ran fine on the way in. I just had the mags IRAN refurbished a month ago and the engine has run fine since.  

Besides technique (which it sounds like you have already mastered), the ignition system is the next key.  Specifically your sos, left mag, harness & plugs.  If that isn’t well sorted, no technique will work.

Do you hear the sos rattle when you turn to start (before pushing the key)?

[Brent]

6 hours ago, Ragsf15e said:

Besides technique (which it sounds like you have already mastered), the ignition system is the next key.  Specifically your sos, left mag, harness & plugs.  If that isn’t well sorted, no technique will work.

Do you hear the sos rattle when you turn to start (before pushing the key)?

Update: (1) I don't know if I'll ever be confident I have the technique mastered, but (2) it looks like I do have an ignition problem. There is little to no current getting to the plugs. We pulled the LH magneto, which checked good, so I guess it's now a hunt to find the thief of the input voltage. Voltage checks at the various switch positions revealed no anomalies, or so it seemed today.

Regarding "sos" rattle (shower of sparks?), I'll listen for that with the mechanic. Thanks for that.

 

[MikeOH]

I'm a little confused by the term "little to no current getting to the plugs".  What/how did you measure?  Also, I don't understand "thief of input voltage". Input voltage to what?  The mags don't require any input voltage?

[N201MKTurbo]

13 hours ago, Brent said:

Update: (1) I don't know if I'll ever be confident I have the technique mastered, but (2) it looks like I do have an ignition problem. There is little to no current getting to the plugs. We pulled the LH magneto, which checked good, so I guess it's now a hunt to find the thief of the input voltage. Voltage checks at the various switch positions revealed no anomalies, or so it seemed today.

Regarding "sos" rattle (shower of sparks?), I'll listen for that with the mechanic. Thanks for that.

 

It says you have an M20J which normally has a dual mag. you said your mechanic removed the left mag. Has your engine been changed out with one with individual mags? If so does each mag have an impulse coupling? If they do, is your ignition switch configured for both mags hot during start?

And if you have a J you don't have a SOS.

[Brent]

35 minutes ago, N201MKTurbo said:

It says you have an M20J which normally has a dual mag. you said your mechanic removed the left mag. Has your engine been changed out with one with individual mags? If so does each mag have an impulse coupling? If they do, is your ignition switch configured for both mags hot during start?

And if you have a J you don't have a SOS.

It's a J model, but it is the SOS ignition system, which was installed with an IO-390 engine by a previous owner in 2011. So both mags are for the SOS ignition system; mechanical impulse couplings. It's a clean set-up - no Frankenstein stuff going on. 

Based on a little more research and waiting for the mechanic to advise further, I believe the issue is upstream of the mags, maybe at the ignition vibrator or the relay between the switch and the vibrator. I guess it could also be the switch, but that seemed to perform correctly on some position/voltage checks. Anyway, step 1 is to get back to the plane and listen for the vibrator buzz, as suggested by another poster above.

References: 

- Useful Don Maxwell article: https://www.donmaxwell.com/shower-of-sparks

- ABCs of shower of sparks systems: https://www.csobeech.com/files/TCM-SOS-IgnitionSystem.pdf

[Brent]

56 minutes ago, MikeOH said:

I'm a little confused by the term "little to no current getting to the plugs".  What/how did you measure?  Also, I don't understand "thief of input voltage". Input voltage to what?  The mags don't require any input voltage?

Thanks for asking; bad semantics by an amateur.

The shop mechanic checked for spark at the spark plug leads and saw little or none while I cycled the key to the start position. Meanwhile, the LH magneto checked out fine on the magneto shop's test rig; it was channeling spark on all four wires. (Mag timing and resistance readings were fine.) In retrospect, the mag coming off was probably off-target troubleshooting, but I'm not going to criticize someone trying to help me - shop labor cost notwithstanding; we'll see about that part. In any case, if current were getting to the magneto, it would be distributed to the plugs or at least some of them, assuming no bad wires. So it seems the something my be interrupting the current upstream, perhaps at the vibrator or relay? Again, this is speculation by an amateur. I do owner-assisted annuals, but I'm no pro. I'll get more feedback when the shop is back on the case later today.

[Shadrach]

5 hours ago, Brent said:

So both mags are for the SOS ignition system; mechanical impulse couplings. It's a clean set-up - no Frankenstein stuff going on. 

There are two devices used to create a late (0°) ignition event for starting:

Shower of sparks - starter vibrator that energizes a retard breaker.

-or-

Impulse coupling - flat spring that is wound and released during rotation to spin the mag fast enough to spark and delivering that spark ~ TDC.

Both of these systems are common, but I have never heard of them being installed together.

[N201MKTurbo]

34 minutes ago, Brent said:

It's a J model, but it is the SOS ignition system, which was installed with an IO-390 engine by a previous owner in 2011. So both mags are for the SOS ignition system; mechanical impulse couplings. It's a clean set-up - no Frankenstein stuff going on. 

Based on a little more research and waiting for the mechanic to advise further, I believe the issue is upstream of the mags, maybe at the ignition vibrator or the relay between the switch and the vibrator. I guess it could also be the switch, but that seemed to perform correctly on some position/voltage checks. Anyway, step 1 is to get back to the plane and listen for the vibrator buzz, as suggested by another poster above.

References: 

- Useful Don Maxwell article: https://www.donmaxwell.com/shower-of-sparks

- ABCs of shower of sparks systems: https://www.csobeech.com/files/TCM-SOS-IgnitionSystem.pdf

So, I have found the easiest way to troubleshoot the SOS, is to just look at a spark plug laying on the top of the engine. With the engine just past TDC the plug should spark continuously with good strong sparks. It just takes a while to get the engine safe to do this. You need to remove all the top plugs and all the bottom leads.

[Shadrach]

1 hour ago, N201MKTurbo said:

So, I have found the easiest way to troubleshoot the SOS, is to just look at a spark plug laying on the top of the engine. With the engine just past TDC the plug should spark continuously with good strong sparks. It just takes a while to get the engine safe to do this. You need to remove all the top plugs and all the bottom leads.

I agree, but listening for the sound (or lack thereof) of the starter vibrator offers a lot of information for very little investment.

[gabez]

this reminds me of my J35, you basically had one start and if you had to start it again good luck. I do agree with the rest of the group the priming after a short taxi did the trick and then you flooded it even more. my m20K is the same, my taxi is about 1 minute and if I try to prime it, it will give me a hard time

[Brent]

Informed members will have probably figured this out, but my lack of knowledge went beyond semantics. The J-model ignition issue I posted about above is associated with a Slick magnetos and ignition system (on an IO-390). I actually thought the Slick system was a type of shower-of-sparks system, but I am learning that it is a replacement for the shower of sparks system. 

So thank you to those who have tried to help me out (I'm still in trouble-shooting mode via the shop) and apologies to those who I confused. I'm learning a lot, regardless. 

[EricJ]

2 hours ago, Brent said:

Informed members will have probably figured this out, but my lack of knowledge went beyond semantics. The J-model ignition issue I posted about above is associated with a Slick magnetos and ignition system (on an IO-390). I actually thought the Slick system was a type of shower-of-sparks system, but I am learning that it is a replacement for the shower of sparks system. 

So thank you to those who have tried to help me out (I'm still in trouble-shooting mode via the shop) and apologies to those who I confused. I'm learning a lot, regardless. 

That's how ya learn! 

Let us know what you find out!

[Shadrach]

11 hours ago, Brent said:

Informed members will have probably figured this out, but my lack of knowledge went beyond semantics. The J-model ignition issue I posted about above is associated with a Slick magnetos and ignition system (on an IO-390). I actually thought the Slick system was a type of shower-of-sparks system, but I am learning that it is a replacement for the shower of sparks system. 

So thank you to those who have tried to help me out (I'm still in trouble-shooting mode via the shop) and apologies to those who I confused. I'm learning a lot, regardless. 

Easy to forgive your confusion. Champion makes an after market ignition booster called “Slick Start”…

 SlickStart™ unleashes a firestorm of ignition energy to get your engine started

[gwav8or]

PIREP on my original issue.

Needed fuel today so I started up, leaned it out.  Taxi to the fuel farm.  Got fuel then went to the FBO for a bathroom break and a bottle of water.

Back to the plane.  Didn't touch anything.  Hit the starter and after about 15 blades it started up.

Thank you all for the advice!!  I just hope the next fuel stop works out the same! lol

Also, I think that my ignition switch is not connected correctly.  From what I've read, the shower of sparks should be activated when the key is turned to start, without pushing in.  However, when I turned the key to start without pushing in the starter engaged.  So, I've got one more thing to add to the list for the mechanic to check out at next annual (September).