Why can't today's cars have magnetos?

AggieMike88

AggieMike88

Touchdown! Greaser!
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The original "I don't know it all" of aviation.
Something went strange with my 2004 Cadillac SRX as I was heading home.

The warning bell went off, the check engine light popped on, and the info screen said something about entering battery saver mode. 200 feet later the car died completely... efforts to jump would get it running as long the two vehicles were electrically connected. But it would quit again when we disconnected.

Battery monitor on the car would show just at 10 volts. And an ammeter is not part of this car's gauge package. Battery is 6 months new.

So I guess I got some sort of problem with alternator or other bit of the charging system.

While I enjoy some of the efficiencies of the modern cars, this incident makes me wish we had magnetos on my car. At least then the engine woulda kept running and I coulda made it home.

As it was, it was 1.4 hrs before the tow truck arrived.

I'm home safe now. Using the salvage yard delivery truck as transportation... And starting to think that piggy banks days are numbered as I google replacement vehicles....

Eff all these electronic bits and bobs on our cars... let's go back to the simpler ignition systems like our aircraft!
 
When I was a kid my folks had a '59 Rambler that had a Continental industrial engine and a magneto. Those cars were built that way at the factory. That ignition system was a supreme pain and the car was forever quitting. Furthermore, magnetos have no spark advance, except for very old mags found on very old cars and old radial engines in airplanes. So magneto systems have a narrow RPM range in which they're efficient enough, such as in airplanes or gensets.

And magneto spark strength is RPM-dependent. At low RPM it has a weak spark. Weak spark means poor power performance.

The points-and-condenser systems used in cars for decades were much more reliable and had a stronger spark at any RPM, and had variable timing to get the best performance out of the engine. But they still needed new points and condenser every so often, and retiming to the engine.

Electronic ignition changed everything. The early systems were a pain and could fail without warning, but that is long past us. Moderns systems are nearly bulletproof. The bigger problem is as you found: these systems need a decent supply of power to operate, and 10 volts indicates a nearly-dead battery. Load that system up with the ignition system and watch the voltage fall to 7 volts, maybe. Even the points and condenser systems are useless at that point.

2004. 14 years is a long time for an alternator. Their field brushes wear out and they stop generating. The battery has to provide the power and it doesn't last long.

Field brush failure is the most common cause of alternator failure in airplanes, too, which is why manufacturers ask for brush checks at every 500 hours. Most don't get it (because it costs money, of course) so eventually most owners are going to experience electrical failure and, if lucky, an inconvenient stopover somewhere until a mechanic can fix things. That can cost a lot more money than 500-hour brush checks. ALternators in airplanes are spinning at or near their redlines most of the time, and those brushes wear out. Systems like the G1000 use a lot of electricity, making the brushes carry more field current to keep the output up, and in those airplanes the brushes wear nearly twice as fast.
 
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RyanShort1 said:
But then you might be replacing it every 800 hours or so on your car...
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That made me think of this golden oldie...
___________________________

For all of us who feel only the deepest love and affection for the way computers have enhanced our lives, read on. At a recent computer expo (COMDEX), Bill Gates reportedly compared the computer industry with the auto industry and stated, "If GM had kept up with technology like the computer industry has, we would all be driving $25.00 cars that got 1,000 miles to the gallon."

In response to Bill's comments, General Motors issued a press release stating: If GM had developed technology like Microsoft, we would all be driving cars with the following characteristics:

1. For no reason whatsoever, your car would crash twice a day.

2. Every time they repainted the lines in the road, you would have to buy a new car.

3. Occasionally your car would die on the freeway for no reason. You would have to pull to the side of the road, close all of the windows, shut off the car, restart it, and reopen the windows before you could continue.

For some reason you would simply accept this.

4. Occasionally, executing a maneuver such as a left turn would cause your car to shut down and refuse to restart, in which case you would have to reinstall the engine.

5. Macintosh would make a car that was powered by the sun, was reliable, five times as fast and twice as easy to drive - but would run on only five percent of the roads.

6. The oil, water temperature, and alternator warning lights would all be replaced by a single "This Car Has Performed An Illegal Operation" warning light.

7. The airbag system would ask "Are you sure?" before deploying.

8. Occasionally, for no reason whatsoever, your car would lock you out and refuse to let you in until you simultaneously lifted the door handle, turned the key and grabbed hold of the radio antenna.

9. Every time a new car was introduced car buyers would have to learn how to drive all over again because none of the controls would operate in the same manner as the old car.

10. You'd have to press the "Start" button to turn the engine off."
 
If the alternator checks out okay, check all the alternator and battery grounds. That's always the first thing I check with charging problems once the alternator and regulator (which may be integral with the alternator) check out okay.

As for mags, they're great for reliability, but not so great for fuel efficiency. I suppose they could be made more efficient, but that would defeat the benefit of their simplicity.

Rich
 
There are lots of ways for cars to leave us stranded besides ignition, or lack of power to it.

I'd had some signs of slightly weak battery on the 2001 mercury grand marquis I usually drive while we had that first cold spell, but no signs of any issues since. Tuesday I made a stop on the way home, and experienced those common symptoms of a broken link between cells. The door locks work, the dome light has a reasonable color, but you turn the key and everything goes dark. Called the wife to bring down the jumper pack, and everything started fine, but discovered that likely the real problem is that one of the factory origional steel band clamp battery terminals split in half. So I'm currently debating diving in fully and replacing both battery cables, and the battery, or a temporary fix and deal with running the full length of the cables on a weekend with more time available.
 
Anyone else see the irony that @AggieMike88 is talking about cars needing parts/maintenance?

Seems he should have some preferential pricing over there at Denton Truck and Auto Parts. And the phone call would likely be local!
 
AggieMike88 said:
I miss Nate not being here.... by now, we'd have something about 1,200 words, and another 20,000 by 3:32am tonight.
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What happened to him. Did the forum software run out of characters ?
 
weilke said:
What happened to him. Did the forum software run out of characters ?
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Sadly, Nate @denverpilot is focusing his attentions elsewhere, but reports to be reading here occasionally. I've reached out to him via SMS to confirm he's in good health and things are well.

I miss him too.
 
You must have never flown an airplane with electronic ignition.
 
Stewartb said:
You must have never flown an airplane with electronic ignition.
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Nice one! I know a guy with a plane with TWO electronic ignitions and Zero mags. I call him me.

0-320 with two lightspeed plasma II ignitions.
 
GMs charging system warnings are asinine and don’t describe the problem. You can get a “charging system failure” or “battery saver activated” warning and it could be any number of causes. In your case, I’d suspect the alternator, but there’s also likely an inductive voltage sensor on the ground cable near the battery that occasionally goes bad.

The battery voltage in the drivers information center is fed from the ECU and the induction voltage sensor. If those two values differ by a predetermined amount, it assumes charging system failure. Thanks GM.


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Because in a car...you can just pull over!

:)
 
SoonerAviator said:
GMs charging system warnings are asinine and don’t describe the problem. You can get a “charging system failure” or “battery saver activated” warning and it could be any number of causes. In your case, I’d suspect the alternator, but there’s also likely an inductive voltage sensor on the ground cable near the battery that occasionally goes bad.

The battery voltage in the drivers information center is fed from the ECU and the induction voltage sensor. If those two values differ by a predetermined amount, it assumes charging system failure. Thanks GM.
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This explains a number things that happened and I saw. Thanks!
 
AggieMike88 said:
This explains a number things that happened and I saw. Thanks!
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My knowledge of the issue is unfortunately from having to deal with a “charging system failure” message on the DIC every day for the past year upon startup, lol. LS4 V8 engine with new voltage sensor, battery, terminals, and alternator. Car runs fine and has for over a year, but I can’t get the message to go away (minor annoyance), I just haven’t broken out the multimeter yet.

To top that off, the GM reman tranny is having issues 2 months outside of the 3yr warranty and they won’t cover it. Car is going up for sale right after I get it back from the tranny shop before anything else can break on it!


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SoonerAviator said:
My knowledge of the issue is unfortunately from having to deal with a “charging system failure” message on the DIC every day for the past year upon startup, lol. LS4 V8 engine with new voltage sensor, battery, terminals, and alternator. Car runs fine and has for over a year, but I can’t get the message to go away (minor annoyance), I just haven’t broken out the multimeter yet.

To top that off, the GM reman tranny is having issues 2 months outside of the 3yr warranty and they won’t cover it. Car is going up for sale right after I get it back from the tranny shop before anything else can break on it!


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Front wheel drive LS... GM's redheaded stepchild.
 
I wish I could have EFI and electronic ignition in my plane. A lot more efficient and a lot more reliable despite the extra complexity.
 
ktup-flyer said:
Front wheel drive LS... GM's redheaded stepchild.
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Yup. Fun car (for a FWD) but man the 2000’s weren’t a great time for GM quality. The Holden/G8 was a much better platform, albeit with basically the same electrical system issues.


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Yep. My alternator crapped out this week and my car got stuck on the side of a highway. It wasn’t fun.
 
SoonerAviator said:
Yup. Fun car (for a FWD) but man the 2000’s weren’t a great time for GM quality. The Holden/G8 was a much better platform, albeit with basically the same electrical system issues.


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Yep, the Zeta platform (G8/VE&VF Commodore/SS/Camaro) is great for a daily, and it’s a great performer with some mods. The LS3 loves to lope down the highway in 6th gear. I’m at 430rwhp and still get 25+mpg on the highway. The only quirk is that they freak out and do weird **** when the battery starts to go bad.
 
ktup-flyer said:
Yep, the Zeta platform (G8/VE&VF Commodore/SS/Camaro) is great for a daily, and it’s a great performer with some mods. The LS3 loves to lope down the highway in 6th gear. I’m at 430rwhp and still get 25+mpg on the highway. The only quirk is that they freak out and do weird **** when the battery starts to go bad.
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I’d love to grab a 2009.5 G8 GXP. Highest HP car Pontiac ever made. They made them with manual trannies and hold their own vs the BMW M-series. Still command pretty high prices on the used market, probably a collectible some day.


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Do the G8 suffer the same curse as the G6? Parts come from Holden Australia, take forever, and cost far more than you would expect?
 
Ravioli said:
Nice one! I know a guy with a plane with TWO electronic ignitions and Zero mags. I call him me.

0-320 with two lightspeed plasma II ignitions.
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Mine uses dual Pmags and API injection. Absolute superiority to a carb and mags. Finally my airplane is following the standard my cars and trucks moved to decades ago. I have no desire to go back.
 
Dan Thomas said:
2004. 14 years is a long time for an alternator. Their field brushes wear out and they stop generating. The battery has to provide the power and it doesn't last long.

Field brush failure is the most common cause of alternator failure in airplanes, too, which is why manufacturers ask for brush checks at every 500 hours. Most don't get it (because it costs money, of course) so eventually most owners are going to experience electrical failure and, if lucky, an inconvenient stopover somewhere until a mechanic can fix things. That can cost a lot more money than 500-hour brush checks. ALternators in airplanes are spinning at or near their redlines most of the time, and those brushes wear out. Systems like the G1000 use a lot of electricity, making the brushes carry more field current to keep the output up, and in those airplanes the brushes wear nearly twice as fast.
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Too bad there are no brushless alternators, or mags with rare earth magnets...
 
There are some extremely powerful magnetos available (I had a lesser item on an blown alcohol drag bike decades ago.) Today's versions can light off mixtures of nitromethane and air that resemble monsoons. They operate from idle to five-figure engine speeds, and take many horsepower to drive. You can have advance or fixed. So there is no technical barrier to using mags.
 
Kenny Phillips said:
There are some extremely powerful magnetos available (I had a lesser item on an blown alcohol drag bike decades ago.) Today's versions can light off mixtures of nitromethane and air that resemble monsoons. They operate from idle to five-figure engine speeds, and take many horsepower to drive. You can have advance or fixed. So there is no technical barrier to using mags.
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Aside from where to fit one in so many modern engine compartments. Plus putting back the weight saved by not having any provisions to mount or drive even a distributor on many engines now.
 
Craig said:
Mike: Find you something with ALH diesel....:cool:
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They're painfully reliable. I've had to do a few things to my wife's (including put the front end back together after not one, not two, but three different animal strikes... It's a mess up there now. A body man, I ain't) but in general the thing won't die... And if it won't die, I can't justify the CTS-V that my wife doesn't know she desperately wants and needs.
 
My bug killed itself at around 340K miles. Had a cam follower come apart and took a chunk out of one cam lobe. If it hadn't have peened the ball for the internal check valve on the edge of the follower bore, it wouldn't have trashed the head. Bought a 2002 Jetta with 177K miles on it and doing a few maintenance items on it and then it will be on the road.
 
Two of the greatest inventions for cars so far, electronic ignition, closed loop, multiport electronically controlled fuel injection.
 
-KLB- said:
Aside from where to fit one in so many modern engine compartments. Plus putting back the weight saved by not having any provisions to mount or drive even a distributor on many engines now.
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Trust me, I'm not an advocate for magnetos on cars—or airplanes. They have their place, however.
The one on my bike was driven by a toothed belt, which would also work on an automobile.
 
GeorgeC said:
Too bad there are no brushless alternators...
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There are. Big trucks have been using them for a long time. They're bigger, so they wouldn't fit a lot of airplane engine compartments. They have a second section behind the generating section that has a stator coil to which the field current is fed. A second rotor section picks it up, on-board diodes rectify it and feed it to the main rotor.
 
Kenny Phillips said:
Trust me, I'm not an advocate for magnetos on cars—or airplanes. They have their place, however.
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We're stuck with them in certified airplanes because it costs so much now to get past regulatory obstacles and the market is too small to support that. The homebuilders have all the freedom there and they use it.

P-Mag has been trying to build an electronic system that plugs into the magneto's spot and provides a hotter spark, variable timing, and no points to burn out. The vibration of the engine and the heat has been causing lots of trouble for them. Magnetos are robust and simple and take a lot of that without trouble.
 
mags@30hp/liter vs ECU@90hp/liter? I think I'll take the ECU.

I'll miss being able to drive without an electrical system once every 15 years. I'll miss the lost performance every day multiple times per day.
 
AggieMike88 said:
I miss Nate not being here.... by now, we'd have something about 1,200 words, and another 20,000 by 3:32am tonight.
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I think he must have got a day job.
Can't imagine what he's doing with all the time he must available now. ;)
 
Ravioli said:
Nice one! I know a guy with a plane with TWO electronic ignitions and Zero mags. I call him me.

0-320 with two lightspeed plasma II ignitions.
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Are they dependent on one battery to work?
 
GRG55 said:
Are they dependent on one battery to work?
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Currently yes, 1 battery, and 1 alternator. The 2019 budget includes a standby alternator to extend beyond the current 45 mins to land in an alternator failure.
 
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