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Failsafe / bullet proof ignition system?

J

Jerry P. Sheppard

Member
I am at a cross roads with my Unison Ignition system. I have roughly 400 hours on my current system with limited complaints. I do like the fact that when I turn the key she fires up in two turns of the prop. However, the manufacture recommends a 500 hour service. Issue is the TBO parts for that 500 service are no longer available for my particular older model. The S/N on the mags are "99" series. If I find a problem during this service I will have to replace the complete magneto(s). Spruce wants $1600 per mag.

So what must I do ? I am considering cutting bait and moving on. Rip out the old and replace with something different. Question is ? what is the right approach. I am leaning torwards a time tested magneto system ? Perhaps - Bendix / Slick Magnetos or maybe the LIGHTSPEED IGNITION I see on VANS web catalog. I have a 0-320 (160 hp) Aero Sport engine.

Any recommendations on a failsafe / bullet proof ignition system?

Thanks
 
Jerry,

I've run all three: mag, Lightspeed, P-mags.

Slicks would be the easiest for you to retrofit. Mags aren't bullet-proof (I know of many failures) and they do also require maintenance and expensive plugs/harness -but you already have that.

Lightspeeds are very good, teething problems long in the past. A very messy install, though, and you need a secondary electric source.

P-mags would go in easy, maybe needing more switchology than you can simply accommodate in your panel. They have had three SBs and are looking to certify, but they have presented more failures to me and my mates. Others report no worries. Overall, an excellent concept, should be best bet after years of mature field service.

Nothing will be failure proof. I say at this point in time that Lightspeed would be most solid and least life-cycle cost if you can stand the installation hassle. P-mags keep me on the edge of my seat, but they run real good otherwise and are easy to install.

John Siebold
 
I keep hoping that by the time I need to replace my Slicks, the P-Mag/E-Mag units will have 500,000 flight hours on them and be bullet-proof enough that I could go with something "modern", for no other reason that to try something new - I have never had a problem with Mags, and unless you have simultaneous independent failures, they are pretty much fail safe. Alas, I ave not yet gotten comfortable with the P-Mags....maybe when I need replacements in a couple more years.

Mags have been around a very long time, and work well when maintained as they are supposed to. I regularly run LOP with my carbed, magged engine, so I have little reason to change.
 
Primer, fuses or breakers, props and ignitions...

With your question, you've arrived at another one of those war topics. Every single ignition (mags, lightspeed, p-mags, etc) has had documented failures. Every single one. Everyone will have a war story, I'm no different and I can point you to several others that will have more...

There is no such thing as bulletproof or failsafe, so I'd suggest refining your search criteria.
 
Jerry,

You have received some VERY good advice on this topic. I have a friend who is building up Super Cub replica and since he plans to use it as a bush plane, he has elected to go with mags simply because they can be serviced in BFNW. That is not necessarily the case with the electronic ignitions.

One other thing to consider, if you have a dead battery, your EI will not fire but a mag will. However, the P-mags can be powered by a 9 volt battery for hand propping. You will just have to bring a battery and some small jumper wires with you. I don?t know if any of this important but is something you should take into account.

The P-mags seem to have the most promise but as others have pointed out, they have had issues. With luck and good engineering, those problems are all behind them.

(Yes, I?m a P-mag fan. 200+ hours w/o a problem.)
 
Jerry P. Sheppard said:
Any recommendations on a failsafe / bullet proof ignition system?

Thanks
Click to expand...

Like others have commented, there are no bullet proof systems. That's why we fly with 2.

Over the years I've gone from mags to Jeff Rose's system to the Subaru ECU controlled ignition and back to mags. I feel good about coming full circle. Mags work and if one reads all of the reports on ignition systems published by the CAFE foundation, they aren't all that bad. In some circumstances below 10,000' the charts would indicate they may even be better for efficiency.

There is a lot of data at the CAFE web site and it is an interesting read if they stop shooting at you long enough to permit such perusal. :) Thanks for you time and commitment in the military. We appreciate it.
 
Good never ending debate...

I'm not saying that these exist on this particular thread, but what comes up frequently on this list are "conclusions" based upon individual or limited experiences, which is flawed if one wants to know something about reliability and probability of failure. Just keep that in mind when making decisions. People who have good experiences tend to not write about them, on either side of an issue.

One thing to consider, that is a sure thing, is the comparison of aviation spark plugs versus auto type. I have really enjoyed the last few annuals where I did not have to deal with cleaning aviation plugs. I just chucked out the $2 auto type plugs and replaced them.

Good luck with sorting things out! Many have one mag and one EI, which would seem to be a good solution for those uncertain which way to go.
 
And the Result

From the Middle East,

First thanks for all the speedy replies concerning this topic. Normally when I read these threads the results of the initial question never make the final thread. Not this time.

My decision that I just emailed to my friend doing the work in Ohio.

A new standard 2 Slick Magneto System (4300 Series). Additionally, the ?Stick Start Kit? which basically does what an electronic ignition system provides with regards to getting a cold engine to fire. Also, a new wiring harness.

Thanks again.

Jerry
 
There are good reasons to have at least ONE electronic ignition - cleaner plugs, better firing, better performance. That said, I kept one of my mags and only installed a single Lightspeed.

I have two used mags (NOT impulse-coupled) - PM me if you would like one.
 
If you got your engine from AeroSport they may be able to do you a very good deal on new mags - send them an email, they were way cheaper than Spruce for me a year ago. I am running one mag and one P-mag, no problems with either in 300+ hours.
 
Bullet proof

I will tell you what works for me , I have a light speed EI with the crank trigger and a Mag. The plugs burn clean and Hot starts are no problem on the fuel injected Aerosport IO360 I do notice that when I turn off the LSE and run only on the mag I lose 5mph (no change on switching off the mag) .
I am not much of a test pilot so I picked products that have the most time on them.
Peter Cavallo



Jerry P. Sheppard said:
I am at a cross roads with my Unison Ignition system. I have roughly 400 hours on my current system with limited complaints. I do like the fact that when I turn the key she fires up in two turns of the prop. However, the manufacture recommends a 500 hour service. Issue is the TBO parts for that 500 service are no longer available for my particular older model. The S/N on the mags are "99" series. If I find a problem during this service I will have to replace the complete magneto(s). Spruce wants $1600 per mag.

So what must I do ? I am considering cutting bait and moving on. Rip out the old and replace with something different. Question is ? what is the right approach. I am leaning torwards a time tested magneto system ? Perhaps - Bendix / Slick Magnetos or maybe the LIGHTSPEED IGNITION I see on VANS web catalog. I have a 0-320 (160 hp) Aero Sport engine.

Any recommendations on a failsafe / bullet proof ignition system?

Thanks
Click to expand...
 
Ignition System Options

I have the engine hung on my -8a with an Aerosport Io-360, but have not started it yet. Currently learning new proane fiberglass descriptors.

I spent a lot of time researching ignition options and was about to go the E-mag route. But during the research process there were a series of postings regarding E-mag / P-mag failures. Since the build process is taking about three times longer than initially estimated (I also have a real job that requires extensive travel) I got over my concerns and was still going to go the P-mag route. However, last year as I approached decision time, a whole new set of E-mag / P-mag problems arose. At which time I said the **** with it - the potential performance advantages were far outweighed by reliability concerns.

One Lightspeed / One Mag - no regrets.
 
I built a 6 with the LASAR ignition, and it worked wonderfully, and has been bullet proof for over 800 hours, between myself and the new owner. I built the 10 with 1 mag and one lightspeed ignition. I really felt the high altitude performance was there due to the lightspeed ignition, as sometimes the timing would show almost 40 degrees of advance up at high altitudes, full throttle and only 16" MP. When I built the 7A recently, I thought I might try the Emag/Pmag and even bought one. As I paid attention to the teething problems mentioned on this list, I decided to go with what I knew worked--- one mag and one lightspeed. No regrets. I will probably do the same on the new 10, except I will use the crank trigger and not the hall effect, as I used the hall effect on the 7 to save some building time and now the seal leaks. Of course, I think the crank trigger is the only option for the 6 cylinders, so my choice might already be made for me.
There's certainly nothing wrong with 2 mags. They work. The electronic ignitions do seem to help with some efficiencies in various configurations.

Vic
 
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