o.k., who gets my new magneto money?

txflyer

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My 0-470 Continental mags are timed out, and they look and perform timed out, so I want to get new mags (not rebuild) and a plug wire set soon.

Any suggestions as to what the best bang for the buck is going to be, and who it's going to be with?

Thanks in advance. :)
 
My 0-470 Continental mags are timed out, and they look and perform timed out, so I want to get new mags (not rebuild) and a plug wire set soon.

Depends on the age of your engine/mags. If the mags were built by Bendix in the late 50s through the early 70s, they were the most bulletproof mags ever built IMHO. I'd get a REAL GOOD overhaul, right down to the case, and keep doing an overhaul until I stripped the threads out of that case. Even they I may helicoil the threads to keep them going a few more years.

Can't say the same for much earlier and later offerings, much less the throwaways that were built so slick. Slick. Get it? :yes:

Jim
 
Yep, gotta agree, if you have a good set of old ones, just rebuild them.
 
Factory rebuilt teledyne continental motors if you want new. Ones I bought looked like brand new. They will even take slicks for core credit.

I was impressed with the quality. There was absolutely no wear on the dog ear flanges or impulse stop pin. Alll the unpainted aluminum was yellow so I can only assume they strip the mag cases and dip allodine them then paint.

I went with Skytronics ignition harness. TCM's were darn high $.

My dad wanted me to build him a set and he ended up buying junk eBay cores and I said there was no way in hell I could duplicate a TCM reman after buying and reading the TCM master service manual. When we got the new ones we knew it was the right choice.
 
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As pointed out Teledyne (aka Bendix) mags are real workhorses and rebuilt ones are fine but if you want to buy new, you can be assured of being able to repair them in time.

If you have old slicks, they're going into the trash bin. They won't even take them for cores. The more recent slicks can be overhauled to some extent. Slicks are nice mags but they're not designed to last for ever with rebuilds. They're essentially disposable.

The question is how much do you fly? If 500 hours is going to take you a long time, get slicks. If you fly a lot, then you may be better off with teledyne.
 
skytronics for the harness (and they make'em any color you want as long as you want one from their list)

new mags? why? do you have Slicks? Okay, then replace with Continental. If they are Continental just have'em rebuilt by someone who knows what they are doing. The guys at Mexia (sp?) know what they are doing...
 
o.k., looks like I'm sticking with my old Bendix hardware since there's no better offering out there it appears. I'm a big fan of: "if it ain't broke, don't fix it." I'm flexible. I don't mind them being rebuilt if they're the best case and gears etc ... it's cheaper too. More avgas for flying!

Mexia? They got a good rebuilder in Mexia? Heck, I could drive there if I had to.

I'll check out Skytronics. If they have 'em, I might get some red wires to match my paint. Thanks everybody. :)


 
o.k., looks like I'm sticking with my old Bendix hardware since there's no better offering out there it appears. I'm a big fan of: "if it ain't broke, don't fix it." I'm flexible. I don't mind them being rebuilt if they're the best case and gears etc ... it's cheaper too. More avgas for flying!

Mexia? They got a good rebuilder in Mexia? Heck, I could drive there if I had to.

I'll check out Skytronics. If they have 'em, I might get some red wires to match my paint. Thanks everybody. :)



That thing is hot! Do you airdrop sunglasses for spectators who watch you land?
 
o.k., looks like I'm sticking with my old Bendix hardware since there's no better offering out there it appears. I'm a big fan of: "if it ain't broke, don't fix it." I'm flexible. I don't mind them being rebuilt if they're the best case and gears etc ... it's cheaper too. More avgas for flying!

Mexia? They got a good rebuilder in Mexia? Heck, I could drive there if I had to.

I'll check out Skytronics. If they have 'em, I might get some red wires to match my paint. Thanks everybody. :)

The old man (forgot his name, he owns the shop at Mexia) came out one Saturday and rummaged around until he found all the parts needed to fix my mag. I fetched BBQ sandwiches from the place across the highway from the airport. Tell'em what you want and they'll fix you up and show you a few neat aircraft if ya wanta see'em. They had a Beech 18 in the hangar when I was there. They were re-building a 210 that some unfortunate soul had tried to fell trees with. Their bread-n-butter work is heavy maintenance on turbo-props.
 
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Thanks guys. When I get the plane back from Avionics Unlimited, I'll get with Ron and we'll figure out what we need, and where it's coming from.

I'm getting the autopilot fixed, and my com2 fixed. While it's in there, I asked Johnny to install a co-pilot ptt on that yoke, and give me a new button on mine.
 
That thing is hot! Do you airdrop sunglasses for spectators who watch you land?


Thanks. When you stand next to it just right in the sun, it can fry your butt! :lol:

Everything we've done we coordinated with the old paint job with the aid of photoshop. Like the mock up picture below and my sloppy airbrush job. I'm thinking about painting the cleveland calipers some good high heat red for a finishing touch, and get two new braided chrome flex lines to go to the hard lines. The old flex hoses I have now have paint peeling off of them and they look like shyste. So I pop pictures into photoshop and experiment.

Should I paint the brake calipers? They get hot. It's going to take a high heat paint job. The color is off a little, but this pHicture gives you an idea. I like the added color down there. What say all? :):redface::dunno:

 
I'd skip the mags, at least one of them, and go with something like this:

http://www.electroair.net/stc_ignition_kit2.html

Electronic ignition with variable advance.... this one being STC'ed I believe for your engine.


If you add in not rebuilding one mag, and maybe getting a credit for it or sell it, then it might pan out but I don't know.

$5500 .. ouch.

Plus you have to install it and then re-build one of your old mags. The old existing two mag setup does the job. :dunno:
 
Street price is about $4900 and it comes with a new harness. If I was going to replace my mags/harnesses with all new, as you originally proposed to do when entering the thread, I wouldn't hesitate since that offset would knock the price down quite a bit. But I like newer/better technology in my plane.... and the ROI would stretch out beyond 5 years at 100 hours a year so it's hard to justify if money is your primary concern.

BTW, I do think they priced the 6 cylinder wrong....and are way off on their twin model. The non stc version 4 cylinder is in the $1800 range... they priced the 6 cylinder exp about $100 more... yet the 6 cylinder STC version is ~$2000 more then the 4 cylinder STC version (which is about $3000). And no discount if you have to buy 2 of them for a twin.... which is where the real market is.
 
Street price is about $4900 and it comes with a new harness. If I was going to replace my mags/harnesses with all new, as you originally proposed to do when entering the thread, I wouldn't hesitate since that offset would knock the price down quite a bit. But I like newer/better technology in my plane.... and the ROI would stretch out beyond 5 years at 100 hours a year so it's hard to justify if money is your primary concern.

BTW, I do think they priced the 6 cylinder wrong....and are way off on their twin model. The non stc version 4 cylinder is in the $1800 range... they priced the 6 cylinder exp about $100 more... yet the 6 cylinder STC version is ~$2000 more then the 4 cylinder STC version (which is about $3000). And no discount if you have to buy 2 of them for a twin.... which is where the real market is.


It depends on what the difference is between rebuilding two mags and buying a new wiring harness for both, as opposed to rebuilding one mag and one wire harness along with the electroair setup.

I have not priced all the costs yet of just re-building my two Bendix mags and buying new wires for both. :redface:
 
I'd be interested in seeing how much fuel mileage improvement is available with the electronic ignition. Are you carbureted or FI?
 
Carburetor on mine.

The spark and reliability of electronic is appealing. They advertise 10 to 15% fuel savings and a little better performance. Cleaner plugs, better hot starts, altitude performance, yada yada ...

I don't fully understand the power curve of adjusting the spark advance for aircraft, but like the timing advance in a race car, it makes sense to me that advancing and retarding the timing in certain conditions would be a good thing.
 
Carburetor on mine.

The spark and reliability of electronic is appealing. They advertise 10 to 15% fuel savings and a little better performance. Cleaner plugs, better hot starts, altitude performance, yada yada ...

I don't fully understand the power curve of adjusting the spark advance for aircraft, but like the timing advance in a race car, it makes sense to me that advancing and retarding the timing in certain conditions would be a good thing.

The other place it will help you is with Mogas. You have a 230hp O-470 right? Or do you have one of the 260hp upgrades?
 
The other place it will help you is with Mogas. You have a 230hp O-470 right? Or do you have one of the 260hp upgrades?


Correct. I have the carburated 0-470-R 230h.p.

And I'm holding a mogas STC. :)

I just wish I could find it.
 
I don't fully understand the power curve of adjusting the spark advance for aircraft,.

The idea is to maximize the amount of downward "push" on the piston by the burning gasoline but not so much that the piston hasn't started down before the serious burning takes place.

When the engine is turning slow, if you advance the spark too far it will ignite and burn BEFORE the piston gets past center and starts down. This is a bad thing in that it will pound a rod bearing flat in no time at all. That is, if it doesn't bend the rod first.

But when the engine is turning fast, you want more advance because by the time that gas gets all lit up and roaring the piston is moving a lot faster and has started way down before you get max push.

THere are mechanical ways of doing the advance, but they can't cover the whole gamut of variables ... octane, altitude, power setting (not RPM), and a few other minor ones. Electronics can take care of all those variables in microseconds sitting on its tush drinking a beer. No problema.

Did that help?

Thanks,

Jim
 
I'd be interested in seeing how much fuel mileage improvement is available with the electronic ignition. Are you carbureted or FI?
I watched a dyno test of EI/Bendix vs Bendix/Bendix. After running it for hours at cruise loads to get stable data, they were almost identical, with the EI using a hair more fuel. (but within the margin of error) Power/MP/RPM were the same.

How does that translate to the real world at altitude? :dunno: Not worth $5500 to find out. My best guess is people are removing their clapped out old mags, replacing with EI and are impressed because their engine is finally running right, not better. Could have had the same results with couple of field overhauls. EI on an aircraft engine is not "newer/better technology", it's "newer/different technology".

And do you want to be stuck at a field with a problem and nobody with any knowledge or parts to fix it?
 
Thanks for the explanations.

I just want two new/rebuilt mags and a new wiring harness I think.

I think just rebuilding the mags, and a new set of wires will improve my performance. I have one mag that drops a little more RPM on runup.
 
My best guess is...

The CAFE foundation did some testing with this particular unit (in the experimental configuration) and the gains were substantial over the Bendix mags at cruise altitudes and economy settings:

http://cafefoundation.org/v2/pdf_cafe_reports/ignition2.pdf
http://cafefoundation.org/v2/pdf_cafe_reports/ignition1.pdf
http://cafefoundation.org/v2/pdf_cafe_reports/ignition3.pdf

Now far be it from me to stand between Pilots and OWT's, but there is a reason that many of the experimental guys and all of automotive have dumped magneto ignition.

It may not be cost effective for the OP but lets not make unsupported claims. CAFE is an independent organization.
 
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I don't fully understand the power curve of adjusting the spark advance for aircraft, but like the timing advance in a race car, it makes sense to me that advancing and retarding the timing in certain conditions would be a good thing.

It is (I've written engine control firmware for one of the big three).

In aviation the timing is fixed, generally 25 BTDC, which is optimal for full power application. As your power goes down (lower manifold pressure) or you're running LOP you want to advance the timing so you can extract more power from the charge.
 
It is (I've written engine control firmware for one of the big three).

In aviation the timing is fixed, generally 25 BTDC, which is optimal for full power application. As your power goes down (lower manifold pressure) or you're running LOP you want to advance the timing so you can extract more power from the charge.


I don't have the timing on mine memorized. But thanks, I didn't know for sure if it was fixed or if mags had some type of mechanical advance. We'll bust into my mags and see what we see and I'll let Ron tell me where to take it from there. If we rebuild them, I'm sure going to get a new set of wires and plugs. I may go with fine wire plugs since I like what I read about them.

But youz guys are making me want electronic badly. :yes:

Wish those prices would come down for us STC'd up the wazoo boys though... sheeesh, five grand for all new ignition stuff nobody even see's .. that's a tough one to get across to flygirl. :sigh::lol:
 
I agree, it's way overpriced.

I think you'll like fine wires.... I can't speak to your 6 cylinder Continental but on my 6 cylinder Lycoming (a O-540 and IO-540 respectively) they helped with starts and LOP operation. In the later case, you want a more exposed spark to reduce lean mis-fires. A cheaper alternative if you engine will take them is the REM37 extended nose plugs.

ae363421-2cdf-4709-afc0-3e09526bb28a.jpg
 
I watched a dyno test of EI/Bendix vs Bendix/Bendix. After running it for hours at cruise loads to get stable data, they were almost identical, with the EI using a hair more fuel. (but within the margin of error) Power/MP/RPM were the same.

How does that translate to the real world at altitude? :dunno: Not worth $5500 to find out. My best guess is people are removing their clapped out old mags, replacing with EI and are impressed because their engine is finally running right, not better. Could have had the same results with couple of field overhauls. EI on an aircraft engine is not "newer/better technology", it's "newer/different technology".

And do you want to be stuck at a field with a problem and nobody with any knowledge or parts to fix it?


If one could eliminate points altogether though, then the reliability of the system increases 100 fold. Nobody sets points as frequently as they should, and they and condensers are the primary point of ignition failures, so I'm not sure I agree that the technology is not better. I grew up with points and always had a matchbook to reset them when they slip, and a spare set and condenser in the glove box for when they burned up. Also gone are ballast resistors. Nowadays with electronic ignition I put some coils in every 150,000-200,000 miles and that's it. With unleaded fuel, EFI, and electronic ignition I don't even change spark plugs. No one can argue the reliability success all that has been. Yeah, if you're a do it yourself guy, it makes it more costly and difficult, but for most people it means not having to take your car to a mechanic.

Working on electronic ignition systems is simple, there are only 3 part sets to fail, the EICM, the coil, and the rotor stator sensor set.

I didn't think it would do much for mileage on a properly tuned engine since it is a steady state application
 
It may not be cost effective for the OP but lets not make unsupported claims. CAFE is an independent organization.
The shop that did the dyno tests sells EI systems. It was in their best interests to prove it's superiority. That was the point of the exercise.
 
The shop that did the dyno tests sells EI systems. It was in their best interests to prove it's superiority. That was the point of the exercise.

I posted a written study by CAFE. Can we at least have the name of the shop and the data points? If you looked at the CAFE study I posted, you'd actually see at high take off power settings, the EI was at performance parity and in some cases slightly less then the dual magneto system. It was however at economy cruise settings the difference favored the EI system. And if you are a LOP aficionado, an electronic system with a long duration spark/wider gap can help things.

I'm not however defending EI's specific system here or their pricing model... but I am stating that electronic ignition as a generality is better then magnetos. That assumes backup power supplies and a competitive price. One could look to light speed engineering for example... which seems to be the favored system on experimental aircraft.
 
but I am stating that electronic ignition as a generality is better then magnetos.

The only argument against that, Jeff, is that I can have an ignition failure in East Undershirt Ohio on a Sunday afternoon and find magneto parts even if I have to make them with a clothespin and two thumbtacks. (Not quite)

WIth electronic ignition, it is wait for a week to let the manufacturer send me the part or system to fix the problem and hope that it is the right part.

Agreed ... technically superior ... but field repair inferior.

Jim
 
The only argument against that, Jeff, is that I can have an ignition failure in East Undershirt Ohio on a Sunday afternoon and find magneto parts even if I have to make them with a clothespin and two thumbtacks. (Not quite)

WIth electronic ignition, it is wait for a week to let the manufacturer send me the part or system to fix the problem and hope that it is the right part.

Agreed ... technically superior ... but field repair inferior.

Jim

The thing there is that those things that you repair with the thumb tacks and clothespin spring don't exist on the EI unit to need repair. The reality is that the points mag rig will leave you broke down more often than the EI will. Also there are plenty of places and pieces for a mag that will have you waiting a week.
 
EI is just too danged expensive for a Conti 6 cylinder.

The bang for the buck just ain't there imo. I'd rather get a tuned all new exhaust for the money.

If EI added 10 to 15% more horsepower, or more perks besides just LOP fuel saving and cleaner plugs MAYBE, then I could buy into it.
 
EI is just too danged expensive for a Conti 6 cylinder.

The bang for the buck just ain't there imo.

Now if it added 10 to 15% more horsepower, or more perks besides just LOP fuel saving and cleaner plugs MAYBE, then I could buy into it.

For the typical recreational use aircraft engine it's probably not worth it. For commercial use it will probably save enough down time and cancelled flights to make it pay. With high power turbo engines I would see more advantage for a private user.
 
WIth electronic ignition, it is wait for a week to let the manufacturer send me the part or system to fix the problem and hope that it is the right part.

Did you confirm that as fact? Name a part on the EI ignition... I'll call and see if they have it in stock and can ship same day. We do have FedEx here in Michigan also. :hairraise:

BTW... I've had magnetos fail in the field... and my AP didn't have the part in the junkbox to fix it the same day. Had to order it.


I do agree with Henning... not worth it for a recreational flyer. And with the pricing on the EI system for a 6 cylinder the ROI is too long (unless I had to replace both my mags and wires). Now the lightspeed engineering unit? I'd drop that one in in a heartbeat if it was legal. I could retard the timing for my takeoff with MoGas on a hot day and then once up at cruise dial in 35d of advance. Now only if the FAA would fully pass the recommendations of the Small Airplane Revitalization Act....
 
Did you confirm that as fact? Name a part on the EI ignition... I'll call and see if they have it in stock and can ship same day. We do have FedEx here in Michigan also. :hairraise:

BTW... I've had magnetos fail in the field... and my AP didn't have the part in the junkbox to fix it the same day. Had to order it.


I do agree with Henning... not worth it for a recreational flyer. And with the pricing on the EI system for a 6 cylinder the ROI is too long (unless I had to replace both my mags and wires). Now the lightspeed engineering unit? I'd drop that one in in a heartbeat if it was legal. I could retard the timing for my takeoff with MoGas on a hot day and then once up at cruise dial in 35d of advance. Now only if the FAA would fully pass the recommendations of the Small Airplane Revitalization Act....



No way I'd ever get my money back flying 50-150 hours a year..

Now, if they passed some rules that I could use the lightspeed unit, I'd be all over it like white on rice. I think a lot of us are secretly waiting and hoping the FAA will do it. I know I am. It would definitely give somebody somewhere in GA a shot in the arm.

Because I know I would put mine in for a complete panel upgrade. :yesnod:
 
Did you confirm that as fact? Name a part on the EI ignition... I'll call and see if they have it in stock and can ship same day.

Perfect. The failure is not at your home field, but at a remote airstrip and it has happened at 5:15 on Friday afternoon. When is "same day" for that?

Now only if the FAA would fully pass the recommendations of the Small Airplane Revitalization Act....

Let's examine that one. You have been a mediocre mechanic for a few years and the FAA opens up the window for ops inspectors. Without a lot of effort you keep your nose clean without doing anything remotely resembling controversial approvals and your white sheet gets to Ok City where you apply for Staff Engineer.

You have reached nirvana. You can now sit on your hiney for thirty years and suck retirement without so much as lifting a finger to help GA. What is the incentive? You approve some wild screwy idea like electronic ignition and the rest of the mossbacks in the department stone you into your cave. There is absolutely NO incentive at the higher levels to stick your neck out for new ideas. None at all.

COmments appreciated.

Jim
.....
 
Perfect. The failure is not at your home field, but at a remote airstrip and it has happened at 5:15 on Friday afternoon. When is "same day" for that?

The "same day" that the parts for your mag that the local mechanic at the remote airstrip doesn't have. Parts is parts Jim regardless if it's 70 year old magneto technology or an electronic board.


"Now only if the FAA would fully pass the recommendations of the Small Airplane Revitalization Act...."

What is the incentive? You approve some wild screwy idea like electronic ignition

The incentive is a directive from congress. The "wild screwy idea" is letting us take our certified aircraft into an "owner maintained category" where we can put this non-PMA'e stuff on our our certified aircraft.

See page 39

http://www.faa.gov/regulations_poli...a/Part.23.Reorganization.ARC.FINAL.Report.pdf
 
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