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Mags to EI

Ok, I'm opening a can of worms but I'm at a crossroads and have no choice. My left mag on my -10 has a stripped shaft and nut. The only thing holding it together was the cotter pin! Thanks Mr. Kotter! I was hoping for the Pmag solution but they aren't releasing (if that is true) until end of Aug and I'm not even in the "first wave." As a result I have to find a different solution. I can either buy a new mag (which I hate, Just flushing $$ down a toilet) or I can go with a different solution. What I have really disliked about other solutions is I REALLY don't want to have to manage a second backup battery.

So..... blast away. I really would prefer a dual setup. I would really like the tractor parts to go away.

Frustrations galore,
Richard
 
You didn't mention if your current setup was with Bendix or Slick mags, but if you currently have Bendix just buy a rebuilt mag and be done with it! You're not "flushing" anything, just performing maintenance on your engine.

~Marc
 
If you're going to EI, take a look at the SDS products. I really think they have an edge over all the other systems offered now. Least expensive, C/S if fantastic and I don't believe there is a reported failure yet.
I'm very happy with mine after trying 2 other systems.
Tim Andres
 
There is no hard requirement for a second battery if ignition is your only problem. The SDS CPI -6 pulls less than two amps per system at max RPM. The more realistic 3 amp total draw for a dual CPI system at cruise power should get you several hours of flight with the existing ship battery. In such a scheme it is easy to hard wire a dedicated circuit direct from the battery (with an appropriate "Emergency" switch) that allows you to dump the master but keep the engine running.

There are plenty of threads that discuss schemes for achieving airliner dispatch reliability, but only you can decide what is required for your mission.

And good on you for dumping the tractor parts!
 
Mag trouble

You might run your mag problem by Arron at Select Aircraft Service in Lancaster Tx. 972-227-9580. You may be able to get your mag repaired/overhauled for a reasonable price while you wait for a EI solution. I used him for the first time last month and was pleased with the outcome and price.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Backup battery required with one mag and one EI?

With one mag and one EI, would a backup battery be required considering the mag AND alternator would have to fail to need it?
 
If you're going to EI, take a look at the SDS products. I really think they have an edge over all the other systems offered now.

Agree. SDS CPI, user-defined dual ignition maps (one for ROP and one for LOP), via the supplied control head.

If you tend toward DIY, consider an EDIS-6 and a Megajolt/E controller, which is also dual map, user-defined via laptop.
 
Surefly

Go look at surefly, I have not installed on my rv10 yet but my neighbor has them on his rv10 and is happy.
 
Richard's issue is not the first I've heard of now with regards to mag drives.

Over the last few years, several people have contacted us looking for a different ignition solution which does not drive off the back of the engine. They've reported bearing failures, drive failures and gear problems. I'm starting to think that this stuff is not as reliable as many people believe. There's simply more to go wrong with all those parts than a crank sensor setup and if something starts chewing itself up back there, the bits will fall into the engine which could get very expensive.

I'd be interested in hearing how many people have had mag drive stuff go bad and also how many people have had an alternator belt break which was properly maintained?
 
I'd be interested in hearing how many people have had mag drive stuff go bad and also how many people have had an alternator belt break which was properly maintained?

I have lost multiple alternator belts on an Aerostar. Every case, it was a symptom of other problems.

Tim
 
My left mag on my -10 has a stripped shaft and nut.

"Stripped shaft and nut" doesn't sound like something that happened in service....which is not to say there is never any trouble with mags, mag hole EI triggers, or the accessory gear train.
 
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"Stripped shaft and nut" doesn't sound like something that happened in service....which is not to say there is never any trouble with mags, mag hole EI triggers, or the accessory gear train.

It seems like the cush drive failed in this case. That's my understanding talking from Richard on this. Maybe Richard can step in and comment or correct that notion.
 
I can tell you I installed the mags about 75 hours prior. They were used mags, but visual inspection showed they were in good condition. The problem manifested during a mag check before takeoff. I got a large rpm drop but the engine continued to run smooth.

you can see the wear in the pictures below.

http://www.barkingpixel.com/mags/leftmag.jpg
http://www.barkingpixel.com/mags/leftmag2.jpg
http://www.barkingpixel.com/mags/magvideo.m4v

If you get the video to play, the impulse coupling did not do that at all when installed. It was good at that time.
 
I can tell you I installed the mags about 75 hours prior. They were used mags, but visual inspection showed they were in good condition. The problem manifested during a mag check before takeoff. I got a large rpm drop but the engine continued to run smooth.

you can see the wear in the pictures below.

http://www.barkingpixel.com/mags/leftmag.jpg
http://www.barkingpixel.com/mags/leftmag2.jpg
http://www.barkingpixel.com/mags/magvideo.m4v

If you get the video to play, the impulse coupling did not do that at all when installed. It was good at that time.

Nasty. Were you able to retrieve all the bits out of the engine? Mags scare me like EI scares some folks. To each their own I suppose. Lots to go wrong inside there...
 
you can see the wear in the pictures below.
http://www.barkingpixel.com/mags/leftmag.jpg

Can't blame Mr. Slick for that one.

The assembly is missing the washer (Slick M3172) under the nut. Nut bottomed on root thread (look at the shaft), but a little "extra effort" got it snug enough to make the mechanic happy...which stripped the threads.

Let's keep it real. It's not reasonable to blame EI installations for builder error, or vice-versa. Good for the goose, good for the gander...
 
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It is impossible to tell if the original repair station made the error or someone long, or not so long, after. I can only tell you that it didn't do that when I installed them and they came off a running engine.

Regardless, it is the catalyst for moving to something a little more modern.
 
Gents, I'm not suggesting you should not switch. If I were rigging a 540 for myself right now, I would select a system that triggered right behind the prop, because the 6-cyl engines naturally exhibit more torsional vibration issues at the accessory end even with pendulum absorbers. That's why they have rubber couplers.

A 4-cyl with pendulums? I'm running dual EI with mag hole triggers right now. I think the timing light is showing me some torsional chatter at around 1500, but run time and inspection says it's not a problem. A 4-cyl without pendulums? A wild card. I have no idea. Front-triggered is probably better.

And allow me to be clear on something. If you think I'm somehow opposed to EI, or electronic fuel injection, you're dead wrong. I am greatly opposed to BS about what they can do, or apples-to-oranges comparisons, or ignorance of how to install or operate them. And I'm definitely opposed to illustrations of "system failure" that are in fact human failure, for mags or for EI.
 
Gents, I'm not suggesting you should not switch. If I were rigging a 540 for myself right now, I would select a system that triggered right behind the prop, because the 6-cyl engines naturally exhibit more torsional vibration issues at the accessory end even with pendulum absorbers. That's why they have rubber couplers.

A 4-cyl with pendulums? I'm running dual EI with mag hole triggers right now. I think the timing light is showing me some torsional chatter at around 1500, but run time and inspection says it's not a problem. A 4-cyl without pendulums? A wild card. I have no idea. Front-triggered is probably better.

And allow me to be clear on something. If you think I'm somehow opposed to EI, or electronic fuel injection, you're dead wrong. I am greatly opposed to BS about what they can do, or apples-to-oranges comparisons, or ignorance of how to install or operate them. And I'm definitely opposed to illustrations of "system failure" that are in fact human failure, for mags or for EI.

A fair commentary Dan. I always appreciate your thoughts and even weighting of pros, cons, cause and effect.

In my view, there are simply less things to go wrong with crank triggered setups assuming they're well designed and properly implemented and just like with mags or rear triggered systems, sometimes they are not.
 
Gents, I'm not suggesting you should not switch. If I were rigging a 540 for myself right now, I would select a system that triggered right behind the prop, because the 6-cyl engines naturally exhibit more torsional vibration issues at the accessory end even with pendulum absorbers. That's why they have rubber couplers. SNIP.

Dan and I have exactly opposite opinions on six cylinder trigger approach. The "control box, coils, crank triggers, backup batteries and associated connecting wires" screams at me that I'm adding complexity and system vunerablies. But - each builder does what he wants - as shall I.

On Dan's specific comment about torsional vibration for an accessor case mount, he does have some foundation for his concern but this is very depending on what you are plugging into the mag hole. So let's compare a standard mag that seems to be working for most people and the 200T series pMag (yeah - I know it will not be out for a few more weeks but that is what I'll be installing on the RV-10).

Internally magnetos swing a sizable magnet past a coil to generate electricity. The drive pad for almost all six cylinder installations turn at 1:5 to 1, which significantly adds to the load the mechanical coupling endures.

The 200T pMag loads on the mechanical coupling are a small fraction of those produced by a magneto. The pMag rotating mass is far less in overall weight and is concentrated much closer to the center of rotation. The result is the 200T pMag loads are tiny compared to a standard mag.

Carl
 
Dan and I have exactly opposite opinions on six cylinder trigger approach. The "control box, coils, crank triggers, backup batteries and associated connecting wires" screams at me that I'm adding complexity and system vunerablies. But - each builder does what he wants - as shall I.

Carl

By all means use what you are comfortable with but be aware about what's inside. With the P Mag you still have a circuit board, CPU, trigger mechanism, wire connections which are not particularly well strain relieved or water proofed, all subject to direct engine vibration and relatively high heat compared to off engine mounted electronics. Have a look inside a P Mag sometime.

I get to talk to lots of folks about their P Mag experiences. That's all I'll say here but maybe you can guess why they are calling us...
 
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I ditched my slicks on my 0-290 when they came time to overhaul. Went with flyEFII dual ignition. Widened my battery box by about an inch to house dual batteries. Rebuilt my electrical system with a ground bus, which is the way I should have done it in the first place. About 50 hours on system and all runs great! My next build will have fuel injection as well. Probably the new system 32 that flyEFII just came out with.
 
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