Surefly at FL’s

[Will.iam]

Has anybody that has a surefly electronic ignition flown it in the flight levels?  I just got off the phone with Maggie harnesses and their tech guy warned me that surefly has been having arcing problems at altitude because even though the Sim will not arc like a an unpressurized mag will they have seen arcing in the cap where the leads are and thus need to pressurize the cap to keep that from happening. I talked to jim Baker that doesn’t do mooneys but does do cirruses and he confimed that you have to get better insulation in the cap or pressurize it where the lead wires enter or you will get arcing in the flight levels. So anybody with a surefly installed, have you tested it up in the flight levels yet? Have you modified the cap to keep this from happening? 

[Will.iam]

So after extensive searching I haven’t found any reports about high altitude flying and arcing in the cap but i haven’t found any reports of turbo charged airplanes with surefly flying in the flight levels either. So I’ll start with the standard install and if arcing happens to me at FL’s I’ll report about it and do the modification that Jim Baker was talking about they do for the cirrus planes that have pressurized mags. 

[Warren]

I just bought a unit and plan to install it soon.  I called their tech support and they certified the unit in a simulated environment (vacuum chamber) into the high 300's.  According to their tech support, they have not experienced any issues at altitude.  Their biggest issue is installers not timing the unit properly -- have to set it up at 0 degrees on the engine and get the dip switches set properly.

I will report back with my experience as well.

[Will.iam]

I think the confusion is the pressurization issues are not in the surefly itself but outside the unit in the cap where the leads are the closest to other leads and can arc. Thus again an installation problem. One solution is to pressurize the cap with the pressure line that came off the old mag that the surefly replaced. Or put in more insulation material to keep the leads more electrically insulated. 

[alextstone]

I'm installing one on my Bravo soon...I'll consider the mods and give a PIREP too.

[Danb]

15 hours ago, Will.iam said:

Has anybody that has a surefly electronic ignition flown it in the flight levels?  I just got off the phone with Maggie harnesses and their tech guy warned me that surefly has been having arcing problems at altitude because even though the Sim will not arc like a an unpressurized mag will they have seen arcing in the cap where the leads are and thus need to pressurize the cap to keep that from happening. I talked to jim Baker that doesn’t do mooneys but does do cirruses and he confimed that you have to get better insulation in the cap or pressurize it where the lead wires enter or you will get arcing in the flight levels. So anybody with a surefly installed, have you tested it up in the flight levels yet? Have you modified the cap to keep this from happening? 

No issues in my Bravo

[Will.iam]

1 hour ago, Danb said:

No issues in my Bravo

How high have you flown with the surefly? And are your sparkplugs gaped at .018 or .036?

[Danb]

I have fine wires, flown 18000

[Niko182]

16 minutes ago, Danb said:

I have fine wires, flown 18000

Any noticeable differences?

[Will.iam]

4 hours ago, Danb said:

I have fine wires, flown 18000

Thanks for the update and data point. 

[Danb]

9 hours ago, Niko182 said:

Any noticeable differences?

Plane hot starts better, may be a little smoother, in cruise fuel usage went from 17 to 16.5, not much 

[kortopates]

don’t believe gap would have any effect on high altitude miss in the cap.


Sent from my iPhone using Tapatalk

[Will.iam]

12 hours ago, kortopates said:

don’t believe gap would have any effect on high altitude miss in the cap.


Sent from my iPhone using Tapatalk

Increasing the spark plug gap increases the resistance to get the spark across that wider gap. Now add the spark plug you are trying to get a spark to jump across to the electrode is in a cylinder with very high pressure air (&fuel mixture) read higher resistance than a sparkplug in an adjacent cylinder that is in the exhaust stroke lower pressure or intake stroke a vacuum and those plugs have a lower resistance for the spark to jump across compared to the cylinder plug you want to fire.  The electricity takes the path of least resistance and in this scenario to the wrong plug. what might pass with lower gaped plugs may fail with larger gaped plugs. 

[Marc_B]

Reviving this thread to see if there's been any updates?  I installed a Surefly with a Maggie harness a year ago at annual and have been up to FL's from time to time and have not experienced any misfires.  My shop didn't offer to pressurize the cap and just removed the upper deck pressure line and the T that went to the previous mag it replaced.

But I was talking to a fellow M20K pilot the other day who mentioned about drilling a hole in the cap for the pressure line...I don't recall coming across the idea of pressurizing the cap previously when I was learning about installing a Surefly.

@kortopates did you pressurize your cap and do you or Savvy typically recommend this?

[kortopates]

Never seen high altitude miss with a surefly or on any EIS yet, so not concerned.
Leaking wires is a different scenario.
I would fear pumping moisture into the Surefly to pressurize the cap would merely serve to reduce its reliability by promoting much faster corrosion. That’s one of the main reason our pressurized mags don’t last as long as unpressurized mags.


Sent from my iPhone using Tapatalk

[Marc_B]

1 minute ago, kortopates said:

I would fear pumping moisture into the Surefly to pressurize the cap would merely serve to reduce its reliability by promoting much faster corrosion. That’s one of the main reason our pressurized mags don’t last as long as unpressurized mags.

Thanks Paul.  That was my first thought as well.  Avoiding needing to pressurize the mag for a turbo Mooney is one of the great selling points for EIS in my book!

[Marc_B]

@kortopates I sent an email to Surefly and their response was a recommendation to pressurize cap...  FWIW I've not been aware of any issues at altitude and have flown routinely in the high teens and low FL's since having the Surefly installed in April 2023.  Sounds like Jim Barker is a Cirrus mechanic and they were running into some issues with Surefly in turbo Cirrus applications flown routinely in the FLs.  hmmm.

"Hello Marc, we have found that when an aircraft is operated at higher altitudes with standard harnesses arcing in the cap can occur due to separation in the wire insulation of the leads at those lower atmospheric pressures. We have since been recommending either a high altitude harness or a pressurized cap or both. A high altitude harness can be manufactured for you by Alan Woods at Champion Aerospace. His e-mail is alanwoods@champaero.com 864-843-7801. And a pressurizing kit can be acquired from Jim Barker of Aviation Resources. His contact info is jim@aviationvibes.com 715-822-5787."

[kortopates]

Thanks for sharing, if i was going to make any changes i’d try their recommended high altitude harness first. But i’ve been free of any high altitude miss yet i know some gap their plugs at the maximum width for the Surefly which isn’t helping.


Sent from my iPhone using Tapatalk

[McMooney]

non turbo, so probably not relevant.  I've had birdy up to 15000 without issue,  one day i'll get her to 18k

[Will.iam]

Also to comment i have had my m20k to 230 and no misfires that i am aware of. How Would a misfire sound / feel like? Is it like a stumble or hesitation or is it more auditory like an after fire since that cylinder just dumped the raw fuel into the exhaust pipe? How would it show up on your engine monitor graphs? Would there be a drop in cht or egt noticeable with only one miss fire? 

[kortopates]

Put your monitor in Normalize mode while in cruise and it will be easy to see as erratic EGT changes. Misfire comes in all degrees from barely noticeable to change in underwear required rough.