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Finally getting back to the "having a running Mooney" project. The engine builder wants overhauled magnetos (even though mine were IRAN'd ~200 hours and ~1.5 years ago). That looks to be about $650/each, plus ~$350 every 500 hours for an IRAN, each mag (more if parts are needed; Aero Accessories pricing, $240 for the IRAN kit plus $110/mag labor, and my most recent IRAN also needed a $185 coil, total bill $944). So, let's say about $2000-2400 over the lifetime of the engine, per mag.

Or ... $1200 for a SureFly electronic ignition (ACS is running a 15% off promotion), 2400 hour lifespan, and all the bonuses electronic ignition is supposed to provide. (Let's say it saves 0.5 gph; over 2000 hours that's a $2,500 fuel savings...)

My existing mags are the Bendix 200s (S4LN-200 and -204).

What should I be looking for? 1969 M20F, IO-360-A1A, everything original more or less (I'm pretty sure it's still using the shower of sparks, etc).

Which mag do I change for maximum modernization (eliminate the SoS, etc)?

Looks like I'll need the SIM4N and a Slick wiring harness (about $500?) (Q&A):

Q: Mooney utilizes the shower of sparks system and does not have an impulse coupler. Would I buy the Sim4p or the Sim4N?
A Shower of Sparks system would be replaced by a SIM4N. As a side note, that is a Bendix magneto and will require the installer to change the spark plug harness with one that mates to a Slick magneto. All SureFly units mate with Slick style harnesses.

Anything else I'm missing? (I'm reaching out to SureFly directly too, just wondered what the collective wisdom of the MooneySpacers had accumulated...) Thanks!!

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The Surefly is great.  Hardest part for an F is taking out enough of the interior to run a power line directly to the battery.  Otherwise the Surefly is good.  Sim 4N is the correct choice.  You’ll be able to remove the left mag and sos.  Your mechanic will have to hook it up to manifold pressure, but that’s not hard.

My engine starts almost like a car and seems to have slightly more power lop at higher altitudes.  Slightly increased speed lop and 10,000’ up.

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Chrix,

Read up around here on all the recent Surefly experience...

There is a lot of success stories, a few trouble spots for installation have been uncovered and set right...

We we’re reviewing JPI data the other day to see if the improvements are real...

I believe it is the Left mag that gets swapped so all the starts get improved... (see Dev’s input below)

There are IO360s, 0360s, and a TSIO520 that have one around here...

It looks like the right thing to do...

The hotter spark works like magic as far as the engine data goes... it actually looks like the fuel is getting more completely burned before exiting the exhaust valve... (Lower TIT for turbo guys, probably lower EGTs for the NA guys...) turbo guys focus on the actual TIT values... for the health of their turbo vanes...

The only thing missing is long term data... that is going to take some time... probably 500 hours to compare to the old mags...

Once you have parallel parked a Mooney... having an electronic mag has got to be a piece of cake..! :)

What did the mechanic not like about the old mags?  They are kind of halfway to their next service stop... too soon to need service... to expensive to not service....?  Probably have some good residual value with the RVers...

PP thoughts only, not a mechanic...

Best regards,

-a-

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"Which mag do I change for maximum modernization (eliminate the SoS, etc)"

Definitely the left one. In addition to still needing the SOS if you go on the right, you'll get none of the starting benefits. 

"Looks like I'll need the SIM4N and a Slick wiring harness (about $500?)"

Cheaper if you can find a half harness, but they are generally not stocked, so long lead time.  There's a lot of spare right harnesses floating around out there because of the Surefly's popularity.

"Anything else I'm missing?"

Not really - you'll have to run a wire to the tail if your battery is back there - perhaps most laborious part of install. 

Make absolutely sure the DIP switch settings are set correctly for your aircraft before install - they can't be changed without removing the unit.

It has a continous low level draw off the battery even when master is off, so use a battery tender or pull the fuse in the power line to the battery. 

You need to pull a manifold pressure input from somewhere to get variable timing  - usually #4 cylinder is most convenient. 

It's timed differently - I think to TDC on #1 using a green light on the back of the unit  - you need a 9V battery on some alligator clips to check the timing. 

 

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9 hours ago, DXB said:

"

You need to pull a manifold pressure input from somewhere to get variable timing  - usually #4 cylinder is most convenient. 

 

Dev- it sounds like you have the variable timing in your C.  

How are your CHTs?  Any performance improvements?

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32 minutes ago, Andy95W said:

Dev- it sounds like you have the variable timing in your C.  

How are your CHTs?  Any performance improvements?

CHTs didn't change much that I noticed. It should make no difference in full power climb and I suppose could lead to higher temps in cruise under conditions where it advances - I didn't fly with it long enough until I  had a new Powerflow exhaust and other work done shortly thereafter, and I have some new CHT issues but I'm not sure I can blame the Surefly.

It does make starts dramatically easier under all conditions. 

I'm not sure I notice the potential effects of added power when it advances either - again probably too subtle to pick up without looking carefully.

What I do notice is that I'm able to lean more without roughness - cruising at 65-70% power in the 8-8.5gph range, which is nearly a 1 gph improvement.  That is a surprise to me - I thought it would only help leaning in people with balanced injectors, because power imbalance among cylinders would get in the way first before difficulty igniting lean mixtures for a carb'd bird.  Given that power imbalance,  I bet CHT on my richest cylinder will keep me from running that lean in the summer.  

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1 hour ago, DXB said:

CHTs didn't change much that I noticed. It should make no difference in full power climb and I suppose could lead to higher temps in cruise under conditions where it advances - I didn't fly with it long enough until I  had a new Powerflow exhaust and other work done shortly thereafter, and I have some new CHT issues but I'm not sure I can blame the Surefly.

It does make starts dramatically easier under all conditions. 

I'm not sure I notice the potential effects of added power when it advances either - again probably too subtle to pick up without looking carefully.

What I do notice is that I'm able to lean more without roughness - cruising at 65-70% power in the 8-8.5gph range, which is nearly a 1 gph improvement.  That is a surprise to me - I thought it would only help leaning in people with balanced injectors, because power imbalance among cylinders would get in the way first before difficulty igniting lean mixtures for a carb'd bird.  Given that power imbalance,  I bet CHT on my richest cylinder will keep me from running that lean in the summer.  

I have a very different engine but I also enjoyed better leaning. I used to be just a tad to rough to run lean of peak.  Now I am able to run lop at least to 72% power and I am planning on trying out other settings too.  My injectors are pretty well balanced but I wouldn't really run lop before, but now I will.  BTW at 72% Lop is saving me 3.8gph.  Now that's some savings!

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Interesting thing to consider...

Spark plugs actually wear out...

Caused by the electrons jumping across the gap...

 

1) It may be possible that the stronger spark may knock a few more atoms off the electrodes.....

2) But... the standard mags emit an extra ‘wasted’ spark during the exhaust stroke...

3) The electronic mag does not have to use the wasted spark, so... it doesn’t.

4) Essentially, keep an eye on the spark plugs the same way... but for a different reason... :)

Wonder if our spark plug people are seeing any differences in plug wear patterns...

PP thoughts only, not a mechanic...

Best regards,

-a-

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13 hours ago, carusoam said:

Once you have parallel parked a Mooney... having an electronic mag has got to be a piece of cake..! :)

What did the mechanic not like about the old mags?  They are kind of halfway to their next service stop... too soon to need service... to expensive to not service....?  Probably have some good residual value with the RVers...

I mean, I'm all about increasing reliability and modernizing my single engine, but the long term plan is still to add a spare jug...

My engine builder won't install non-overhauled accessories, including the magnetos, even though they were gone over recently by Aero Accessories and are in great shape. At this point in the pain process, it's a rounding error...

(The $650 price is after a $300 core charge refund when I mail back my existing mag(s).)

 

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1 hour ago, David Lloyd said:

Saw this on another site, if you need to buy half a harness to go with your Surefly:  https://www.newhorizonsmaggieaircraftignitionsystems.com/

The Slick style I ordered from Spruce (Champion) for the Surefly replacing the left mag was marked with the same plug locations as the right mag Bendix harness.  Hmmm.  I ended up putting all the Surefly leads on the bottom plugs and the right mag leads are on the top plugs.  I’d ordered a new Champion harness at the same time for the right side, but they (Champion, not Spruce) sent the wrong model (transposed the numbers) and I wasn’t going to wait another month lead time to manufacture and ship.  

tom

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I just ordered the Sure Fly ignition for my 1966 C. I talked to the SureFly people at Oshkosh and told them I had replaced my old vibrator with a SlickStart unit a long time ago and asked which mag I should replace. He said I could keep the SlickStart and left mag, installing the SureFly on the right side, then I would be using both to start the engine, which is what I am going to do. I had replaced the old vibrator because my points were shot, it made more sense at the time to go with the SlickStart. 
I went with Aircraft Ignition Services for the harness. The harness was $259.00 with 90 degree plug fittings plus shipping. Both SureFly and Aircraft Ignition Service have been very nice to work with, we’ll see how delivery goes. 
I have a friend with an O-540 on his Comanche who can’t say enough good about his results, which encouraged me to install one. I’ll report back with any interesting observations on the install.

Edited by Steve
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24 minutes ago, Steve said:

I just ordered the Sure Fly ignition for my 1966 C. I talked to the SureFly people at Oshkosh and told them I had replaced my old vibrator with a SlickStart unit a long time ago and asked which mag I should replace. He said I could keep the SlickStart and left mag, installing the SureFly on the right side, then I would be using both to start the engine, which is what I am going to do. I had replaced the old vibrator because my points were shot, it made more sense at the time to go with the SlickStart. 
I went with Aircraft Ignition Services for the harness. The harness was $259.00 with 90 degree plug fittings plus shipping. Both SureFly and Aircraft Ignition Service have been very nice to work with, we’ll see how delivery goes. 
I have a friend with an O-540 on his Comanche who can’t say enough good about his results, which encouraged me to install one. I’ll report back with any interesting observations on the install.

Are you going to rewire your starter switch to prevent it grounding your right (SF) mag during start?  

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1 hour ago, Steve said:

That’s the plan. Considering installing the Electroair EA-13000 ignition Switch Panel. I’m dropping enough money right now it will likely wait a bit. 
https://www.aircraftspruce.com/catalog/elpages/ea-ignswchpanel.php?clickkey=18187

That switch panel is nice looking.

In my opinion, I wouldn’t go to much (or any) trouble rewiring my system to start on both mags.  The Slickstart or SF both start really well by themselves (SF is close to a car - smooth).  If one of them isn’t working or can’t start the engine by itself as designed, I think I don’t want to fly the airplane until the ignition system is working properly.

There is one very minor drawback to the SF being on the left mag - with a dead battery you lose the ability to hand prop it.  My limbs and I made peace with that when I had the SF installed.

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The Electroair option is attractive... and STC’d.  In the end, though, it’s just two rocker switches and a start button.  Couldn’t the same be accomplished with three independent MS35058 toggle switches?  For maybe a third of the cost?  All it would take is two standard SPST toggle switches, one for each mag position, and one spring-loaded SPST toggle switch for the starter solenoid.  What we loose when the Bendix-style mag switch is replaced with the Electroair panel is the key.  The Electroair doesn’t have a key.  So what’s the downside of just putting in some toggle switches?  They’re standard parts, no STC required.  Panel space is a premium in the vintage birds.  I’m contemplating putting my toggle switches in the dead space at the top of the center stack, same as where the M20A/B had their push/pull master switch and mag switch.

This is a simple log book entry.  Nothing major.  Am I missing something obvious?

tom 

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If you're looking at those starter switches, you'll need the EA15000 switch panel. The EA13000 has limitations in the STC that only allow it to be used with Electro airs Electronic Ignition. as to the 2 types of ignition systems, I'm thinking hard between the Electroair and the Surefly system. All the Electro air setups have performance gains or less fuel flows while a lot of the Surefly systems aren't gaining any form of performance. Obviously the 3 grand difference in price pays for a lot of fuel but the Electro air EIS seems more sophisticated. I also have no issues with hot starts, which means switching to surefly wouldn't really gain me anything.

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6 hours ago, Niko182 said:

If you're looking at those starter switches, you'll need the EA15000 switch panel. The EA13000 has limitations in the STC that only allow it to be used with Electro airs Electronic Ignition. as to the 2 types of ignition systems, I'm thinking hard between the Electroair and the Surefly system. All the Electro air setups have performance gains or less fuel flows while a lot of the Surefly systems aren't gaining any form of performance. Obviously the 3 grand difference in price pays for a lot of fuel but the Electro air EIS seems more sophisticated. I also have no issues with hot starts, which means switching to surefly wouldn't really gain me anything.

Why would one or the other, electro air or surefly give you more help with hot starts?

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SureFly data on MS is actually showing a performance gain... using JPI data, seeing a change in EGTs and TITs...

I would hate to have to use data provided by the manufacturer to capture a few small percentage points...

Like how good is a PF muffler...

The small percentages take a lot of detail... on individual cases...

Its still early in the game...

Expect better fuel burns, and better starts and hot starts....

The jury is still out on longevity.... but the electronic mags don’t have plastic gears immersed in ozone either... :)

PP thoughts only, I still have the old mags...

Best regards,

-a-

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  • 2 weeks later...
  • 4 weeks later...

I understand some have installed their Shurefly so that it feeds just the bottom spark plugs.  I think most have left their spark plug harness as original with some wires from the Shurefly going to the top plugs and some going to the bottom plugs. Does anybody have any data comparing these two options?

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Some logic why it was done one way... that may no longer apply...

1) Time between failure of standard mags... is too often... around 1000hrs...

2) Botton plugs are most often susceptible to failure because of oil fowling...

3) Electronic Mags produce a stronger spark...

4) Stronger sparks are less susceptible to oil fowling...
 

5) Top and bottom plugs were evenly distributed between mags...

6) Even distribution allowed for similar power being produced during single mag ops...  Not the best, but not the worst...

7) The last thing you want... is a sole, standard mag, operating only bottom plugs... (worst combination)

8) under ordinary conditions, a double failure doesn’t happen... plug and mag...

9) Some plugs have a way of hiding their failure.... until you are replying on them to be working 100%...

10) Under ordinary conditions it doesn’t matter which mag drives which plugs... they are distributed around to spread out risk...

11) with an electronic mag, the risk has changed its nature...
 

12) Drifting /increasingplug resistance (thanks champion) is a way plugs fail without much warning Or hints...

PP thoughts only, not a mechanic...

Best regards,

-a-

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My thoughts with having the higher ignition spark on the same side of all the cylinders either bottom or top have to do with uniformity of the ignition generated flame fronts between all cylinders.  This might make for a smoother running engine.  
Just wondering if anyone has tried it both ways, all one side versus staggered?

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