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E-Mag Pirep

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Check the bearing

We do find a few of these PMAGS with bearing play every year, so please do check them. EMAGAIR has been very quick at truning them around.

Vic
 
We do find a few of these PMAGS with bearing play every year, so please do check them. EMAGAIR has been very quick at truning them around.

Vic

Not saying I would do that, but what would happen if you ran it to failure? I like to understand the edge cases.
 
Not saying I would do that, but what would happen if you ran it to failure? I like to understand the edge cases.

Probably the same thing that happens when a neglected impulse coupler fails, parts fall into the accessory case and cause bad things.
 
FWIW, I emailed P-Mag to ask some questions about the bearings in the 6 cylinder P-mags vs. the 4 cylinder units. I have 6 cylinder P-Mags but the engine hasn't been run yet (other than on the test stand).

Regarding the bearings in the 4 cylinder P-Mags, Brad replied that the 4 cylinder units have one large bearing and one smaller bearing in the stack whereas the 6 cylinder units have two of the larger bearings on the main drive.

The small bearing in the 4 cylinder stack has recently been enlarged.

I'm not sure if that means that older 4 cylinder units sent to P-Mag for service will get the enlarged smaller bearing or if it means that new production units come with the enlarged smaller bearing? But I thought it was worth noting here, since there was discussion of bearing wear and inspection.
 
Probably the same thing that happens when a neglected impulse coupler fails, parts fall into the accessory case and cause bad things.

Thanks Walt. Doesn't sound like something we want to happen.
 
Not saying I would do that, but what would happen if you ran it to failure? I like to understand the edge cases.

Magnet air gap is also something to consider. Aside from the trash generated from a bearing coming apart in your accessory case (accessory gear timing is kind of important), magnet misalignment caused by an out of true shaft is likely to cause a shutdown, or worse, a mistiming event.
 
I made some cooling shrouds for the front of the PMags out of Carbon Fiber. They wrap half way around the PMag and have a 1" blast tube hooked to them. They were easy to make and make the blast tubes more effective. I used the rounded end of a 2X6 for a mold and tapered it just a little to make the shroud easier to get off the mold.

Hi Robert,

Would value seeing a picture of what you made if you don’t mind posting.

- Brian
 
Yes bearings were changed and retrofitable. I talked to Brad he said no need to change if play and rotation are good. A non mandatory change but small incremental changes, r
continuous design improvements. But the original design is fine and many PMags are in service with 1500 hrs or more, with no bearing issue. Just inspect you are good.

Yes bits in accessory case is bad. The PMag is not the issue but some aftermarket gears made for a time with less hardness. This is the same non impulse magneto gear used on your magneto. Two things: The load on gear is light and many of these softer gears have no issue. Second the issue was not wide spread, but there were a few cases of premature wear.

Another good reason to remove PMag yearly to inspect shaft play and rotation, as well as gear. You can assure you have the better or OEM Lycoming gear through markings or hardness test. A genuine non impulse Lyc gear is $450. A non certified gear is $225., which is equivalent to the Lyc gear.
 
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Bearing Failure 6 Cylinder EMag

I had the forward bearing fail on a 200 series (6 cylinder) EMag

My first clue that there was a problem was when I changed the oil and found some small pieces of metal in the filter. I pulled the screen in the oil pan and found a bigger piece of metal that obviously was from the cage of a bearing. I pulled the mags to check the bearings on the mag drive and discovered that it was the bearing on the PMag that had failed. I pulled off the exhaust and the entire intake system as well as almost everything else firewall forward. Then I put an engine crane on it and pulled the bottom engine mounts and loosened the top ones to only a few threads left. Then I was able to remove the oil pan. There was nothing in the oil pan except some fine ferrous metal that showed up with a bright light on it. I used a bore scope to check the accessory case for any damage as well as look on top through the drain holes where the cylinders are. No small pieces of metal were found and no damage was detected. I reinstalled the oil pan with a new gasket and reassembled everything else. This was a 4 day project for me because I am 71 now. When I was 30 I could have got it done in 2 days. There was no surprise when my oil analysis came back with some ferrous metal in it. I shipped both the EMags back to EMag Air and they replaced all the bearings in both of them and shipped them back no charge. An AI on the field mentioned that there was an AD on Bendix Mags because a number of them were assembled with bearings that were manufactured with no lubricant in them. I am suspicious that the same thing happened here. There is very little load on the 200 series EMags because of the way they are driven, with the drive lugs between two rubber spacers in the mag drive on the accessory case. There were some issues with the 200 series EMags when they came out. I had some of the early ones that were anodized a gold color. They recalled all of them and fixed them for free for everyone. I am generally fairly confident in their current product. I think this bearing failure was a bearing manufacturer problem.
I am generally pleased with the 200 Series (6 Cylinder) EMags. The engine starts easily and runs great. I also got my injector restrictors tuned with the help of Don Rivera at Airflow Performance. My number 2 cylinder was peaking well before the rest making running LOP impossible. After tuning, they all peak within .2 gal/hr. Now I am using 21 inches of MP and 2300 rpm at 10.5 gal/hr (55% hp). At 10-12 thousand feet I get 170-175 Knots TAS which works out to 16 nm/gal. (I have a Barrett engine with cold air induction that is rated for 290hp) That gives me 800nm on 50 gal with a 10 gal reserve. At 12,000 feet I am very close to full throttle to maintain 21 inches MP. I have flown the aircraft up to 18,000 and had on issues with the ignition system at all, unlike unpressurized magnetos that can start causing problems as the air gets thin.
When I started running lean of peak the CHT’s actually dropped about 20F from what they were when I was running rich of peak.
I am curious how well others are doing LOP with magnetos. Let me if any of you have any information.
I friend of mine installed the EFI32 electronic fuel injection and ignition on his RV10. This is automotive technology and it seems to work well for him. The down side is that you have to have a substantial backup battery for it because the electric fuel pump is always running. (There is no engine driven fuel pump). I am a bit of the school of “keep it simple”. My Airflow Performance FM300 is totally mechanical and is quite simple. I can deal with having to adjust the mixture.
This forum has been a valuable resource as I was building my RV10. I hope to contribute some of what I have learned for the next generation.
 

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Seems to me that there are significant pros and cons:

PMAG: Install is simple like a mag, but you have to remove and inspect every 100 hours as their is the possibility of it failing in such a way that it will drop metal into your engine (like a real mag). Some report the timing being too aggressive and high CHTs, others report no issues, others report they backed it off with an EICommander, others report they set less base timing. Another con is electronics bolted to a hot vibrating thing.

SDS CPI2: Install is much more involved with coils, wires that pass through the cockpit, magnet holes on the flywheel, etc. Once it's flying you don't need to do anything beyond inspect the wiring at annual. This system maintains it's own backup battery which eliminates all of the complexity of redundant electrical systems, but you have to find a spot for it and it's another battery to maintain. One nice thing is the ability to set whatever timing curve you want from the cockpit but you have to find a spot for the little head unit.

Others: Install is like the CPI in that you have a brain box and coils and pickup, but you need to design an electrical system able to provide backup power and/or detect alternator failure and shed load. Some have more timing flexibility than others.

From my perspective the power redundancy is moot given the CPI2's ability to maintain, charge, and swing to it's own battery backup. The real question for me is which is more reliable, which is more difficult to install, which is more flexible, and which will require more maintenance.

I'm much more comfortable with a battery backup than bearings I have to look at every 100 hours, and I don't care how hard it is to install it as long as I only have to do it once. 100 inspections are a deal breaker for me as I frequently do long cross country trips (I've been as far west as Platinum AK and as far east as OSH) so I would likely find myself in a situation where I need to pull the mag before a major trip, and knowing my luck, I'd find a loose bearing.

Others are much more comfortable with simple install and gears/bearings. I think the right solution is a simple matter of if you prefer gears, bearings, and generators to keep the fan going, or are you more in the camp of magnets, sensors, and backup batteries?

schu
 
I am curious how well others are doing LOP with magnetos. Let me if any of you have any information.
I friend of mine installed the EFI32 electronic fuel injection and ignition on his RV10. This is automotive technology and it seems to work well for him. The down side is that you have to have a substantial backup battery for it because the electric fuel pump is always running. (There is no engine driven fuel pump). I am a bit of the school of “keep it simple”. My Airflow Performance FM300 is totally mechanical and is quite simple. I can deal with having to adjust the mixture.

I think I'm educated enough to comment, but others correct me if I'm wrong.

From what I understand a very lean mixture is harder to light than a rich one, so it makes sense that EI will ignite mixtures a mag won't which allows you to get further LOP. Also, EI can give you some timing which is helpful because leaner mixtures burn slower, so you advance to have the peak pressure in the right place.

As for EFII, I don't feel like there is any significant fuel savings because you can set the mixture to whatever you want in our dumb tractor like single throttle setting vehicles. I think EI is most of the advantage which you have.

That said, EFI can in theory run really crappy fuel and not vapor lock because the entire fuel system is under high pressure. So, the pro is burn whatever gas, and the con is the duplex valve, return line, and need for backup power systems.
 
I had the forward bearing fail on a 200 series (6 cylinder) EMag

My first clue that there was a problem was when I changed the oil and found some small pieces of metal in the filter. I pulled the screen in the oil pan and found a bigger piece of metal that obviously was from the cage of a bearing. I pulled the mags to check the bearings on the mag drive and discovered that it was the bearing on the PMag that had failed. ... I shipped both the EMags back to EMag Air and they replaced all the bearings in both of them and shipped them back no charge. An AI on the field mentioned that there was an AD on Bendix Mags because a number of them were assembled with bearings that were manufactured with no lubricant in them. I am suspicious that the same thing happened here. There is very little load on the 200 series EMags because of the way they are driven, with the drive lugs between two rubber spacers in the mag drive on the accessory case. ... I think this bearing failure was a bearing manufacturer problem.
...
This forum has been a valuable resource as I was building my RV10. I hope to contribute some of what I have learned for the next generation.
Robert, thanks a lot for sharing your experience. Do you happen to know who was the bearing manufacturer?

90% of my bearing experience is with 2-stroke motorcycle engines many years ago, and this kind of failure even then was very rare, and usually the result of the engine throwing a rod or ingesting a lot of dirt/sand. I worked in a machine shop and I was the "engine overhaul guy", so I saw some things.

Bearings are not a good place to try to save money in any product.
 
Robert, thank you for sharing your experience. Four days is a chunk of time/effort but thankfully you didn't have any further engine damage.

I'll be keeping a close eye on my two E-Mags and sending them in to Brad during my condition inspection next month. Hopefully this is only an isolated incident.
 
……..As for EFII, I don't feel like there is any significant fuel savings because you can set the mixture to whatever you want in our dumb tractor like single throttle setting vehicles. I think EI is most of the advantage which you have.

That said, EFI can in theory run really crappy fuel and not vapor lock because the entire fuel system is under high pressure. So, the pro is burn whatever gas, and the con is the duplex valve, return line, and need for backup power systems.

I’m a big fan of EFII….(both EFII/S32 and SDS). True, it’s a more involved installation; especially in an already flying airplane, but once installed it’s basically maintenance free. Everything is solid state, so there’s really no moving parts and nothing to wear out. Yes, proper redundancy needs to be incorporated into the installation, (second battery or backup alternator), but that’s just part of the deal.

I agree, when looking at fuel efficiency, I think most of the benefits are derived from the electronic ignition and its variable timing, but the electronic fuel injection sure is nice as well. Having the ability to run car gas without having to worry about vapor lock along with perfectly balanced CHT’s is a huge plus.
 
E Mag bearing failure.

I cannot quite read all of the spec on the bearing but here is my 2P comment.

This looks like a classic cage failure which is usually caused by
1. Misalignment.
2. Vibration.

Misalignment is a manufacturing or assembly problem which I would find highly unlikely in this case having seen the standard of E Mag in the small samples of the ones I have seen. But could be caused at the Mag engine interface.

If it is vibration then then are a couple of things to consider.

Bearing clearance tolerance.
A point to note that most electrical bearings have a CN close tolerance for quiet running but this tolerance is not so good for vibration and a wider C3 tolerance is more vibration tolerant.
Cage design.
Pressed metal cages are not good in high vibration situations as they fatigue fail.
MB cages are designed for high vibration situations, in fact would help in both situations.

So fundamentally a good bearing engineer would be able to recommend a solution as long as they are aware of of not only the loading but the vibration environment.

These are just my thoughts looking at this single isolated failure.

I must also point out that I think E Mags are a great piece of kit having spent some hours behind one. Starting is great.

Rob
 
How many bearing failures? Max hours before failure? Data would be good. I talked to Brad and it's not systemic, and easy to inspect annually.

We heard from the EFII and SDI fans. I suspect ppl singing the praise never owned or flew with these. What these two have is EFI option.

What about FlySafe, Electroair and Lightrspeed speed.

There is no hard data. It's all preferences. However as a dual P-Mag guy I can say Brad at E-Mag Air is top customer service. There are high time E/PMags with original bearings.

However true Heat and Vibration is a challenge and the same one traditional Magnetos have which are reliable. There is very little load on the bearings.
 
If I'm not mistaken the reason the 6 cyl engines have rubber mag isolators and no more impulse couplings is due to failures caused by vibration and harmonics.
 
I cannot quite read all of the spec on the bearing but here is my 2P comment.

This looks like a classic cage failure which is usually caused by
1. Misalignment.
2. Vibration.

Misalignment is a manufacturing or assembly problem which I would find highly unlikely in this case having seen the standard of E Mag in the small samples of the ones I have seen. But could be caused at the Mag engine interface.

If it is vibration then then are a couple of things to consider.

Bearing clearance tolerance.
A point to note that most electrical bearings have a CN close tolerance for quiet running but this tolerance is not so good for vibration and a wider C3 tolerance is more vibration tolerant.
Cage design.
Pressed metal cages are not good in high vibration situations as they fatigue fail.
MB cages are designed for high vibration situations, in fact would help in both situations.

So fundamentally a good bearing engineer would be able to recommend a solution as long as they are aware of of not only the loading but the vibration environment.

These are just my thoughts looking at this single isolated failure.

I must also point out that I think E Mags are a great piece of kit having spent some hours behind one. Starting is great.

Rob

I really appreciate your input on this. Your knowledge of bearings is vastly greater than mine.
On the Lycoming 540 there are two rubber (or rubber looking) pads that the Emag drive lugs fit between. I would think that they would dampen vibration somewhat, but it in not clear at all to me how effective they might be. If there s a mis alignment problem I have no idea how it could be fixed. The mag drive is only supported with a bearing on the forward end. The aft end is attached to the Emag with the rubber drive coupler.

The bearing cage was a pressed metal one in this case. Can you explain what a MB cage is. I would like to increase my knowledge in this area a little more.
 
The bearing cage was a pressed metal one in this case. Can you explain what a MB cage is. I would like to increase my knowledge in this area a little more.

The MB refers to a Machined Brass cage replacing the stamped steel cage.
 

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We heard from the EFII and SDI fans. I suspect ppl singing the praise never owned or flew with these. What these two have is EFI option.
....
However true Heat and Vibration is a challenge and the same one traditional Magnetos have which are reliable. There is very little load on the bearings.

There are for sure just as many (more?) e-mag fans. Lots and lots of people install these things, and far and wide people love the choices they make, as long as there isn't a reason not to.

I'm actually surprised at how many people view 100 hour inspections and similar (to a mag) modes of failure acceptable. If I'm going to replace a mag with something else, then I'd rather get rid of the entire thing and install something that isn't bolted to the hot vibrating engine as that is for sure working against reliability.

Walt said:
If I'm not mistaken the reason the 6 cyl engines have rubber mag isolators and no more impulse couplings is due to failures caused by vibration and harmonics.

From what I gather the 6 cyl p-mag has a gear train in it because the engine gears drive the unit at a 1.5:1 ratio which would make it very difficult to know where in the 4 stroke we are at startup. I wonder what is in side of a surefly....

Anyway, this adds to your point where the 6 cyl p-mag is far more complex from a bearing and harmonics perspective. I wouldn't guess that the 4 cyl models reliability could be assumed for the 6 when it has all of the extra moving parts.

Hopefully this thread educates people looking at these things. There is for sure a bit of nuance.
 
The pMags have been the most unreliable component in our (now former) RV-7A. Although I have gotten pretty quick turnarounds from the company, the number of times the pMags have been back to them has been unacceptable.

I now regret not converting to SDS CPI-2 last year when the engine was removed for cylinder replacement. I should have just gone ahead and pulled the pMags then. As I recall, my biggest concern was trying to find space for the ECU and backup battery.
 
Likely the first 4 Cyl IO-360, angle valve, 9:1 or higher C.I. with an experimental Hartzel 2 blade composite test version of the Claw was on a friend's Pitts S1T.

It had a harmonic that caused repeated failed magnetos. This was mid 1990s.

Not all engine/prop combos on even the same engine likely have the same outcomes, but the subject bearing location has a history.
 
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From what I gather the 6 cyl p-mag has a gear train in it because the engine gears drive the unit at a 1.5:1 ratio which would make it very difficult to know where in the 4 stroke we are at startup. I wonder what is in side of a surefly....

You can be assured that it has a gear train to bring it down to 1:1 or possibly up to 2:1. While some more advanced ECUs (for EFII typically not for ignition) will also have cam position (2:1) pretty much all Electronic fuel injection and/or ignitions need a spinning apparatus that mimics the crank rotation. Once they know the rotation with TDC, they use math to deal with the cylinder counts and any unique angles related to piston movement. You can get creative and use 2:1, like an old distributor take off, but no fractions. Downside here is that it takes longer to find TDC at start up, though creative use of multiple pickups can reduce that when not limited to using a missing tooth wheel.
 
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If I'm not mistaken the reason the 6 cyl engines have rubber mag isolators and no more impulse couplings is due to failures caused by vibration and harmonics.

If you are not running the Bendix shower of sparks with the starter vibrator then you have to have at least one magneto with an impulse coupler. They still use the rubber mag isolators. I ran with one of those before the 6 cylinder Emags came out.
 
You can be assured that it has a gear train to bring it down to 1:1 or possibly up to 2:1. While some more advanced ECUs (for EFII typically not for ignition) will also have cam position (2:1) pretty much all Electronic fuel injection and/or ignitions need a spinning apparatus that mimics the crank rotation. Once they know the rotation with TDC, they use math to deal with the cylinder counts and any unique angles related to piston movement. You can get creative and use 2:1, like an old distributor take off, but no fractions. Downside here is that it takes longer to find TDC at start up, though creative use of multiple pickups can reduce that when not limited to using a missing tooth wheel.

Yup, this is why I wend with SDS. Two hall effect sensors and magnets seems more reliable than gears, bearings, electronics, and a generator bolted to the engine.

All of this said, there is an entirely new realm of failures that are unique to this style of ignition system:

1. Mechanical failure of the sensor like bolts coming loose or alternator belt taking it out.
2. Installation issues like wires chafing or shorts.
3. Electrical system issues like alternator regulator failure and lacking crowbar protection.
4. Coil failure.
5. Computer controller failure.
6. Issues with the auto plugs or adapters.

How many people have had (or heard of) these failures when using an EI system that has a crank pickup?

I think the CPI-2 deals with #3 with the backup battery and it's internal crowbar circuit when the voltage gets to 24v. The other issues should be common to all of these types of ignition systems.
 
Every ignition system ever designed has the possibility of failing. That is why we traditionally have always used 2 ignition systems. Any system that is not self powering requires a decent sized battery backup. There are no perfect solutions. A friend of mine bought a nearly finished RV8 with the laser system on it. The only way to check timing was with an automotive timing light from the cockpit, with the engine running. All RV’s I have ever seen have seals and baffles over the top of the engine just aft of the starter gear. All that would have to be removed to check the timing, as well a building a pointer to accurately see there the flywheel is. You are also going to need some binoculars to see the marks from the cockpit. I am curious how other systems deal with checking the timing. The EMag’s are super easy to time very precisely. They have advance for lower power settings which improves fuel economy and they are easy to install and time.
 
If you are not running the Bendix shower of sparks with the starter vibrator then you have to have at least one magneto with an impulse coupler...

Not true. My Rocket had neither impulse couplers or shower of sparks type booster when I purchased it. Just two raw magnetos. Started fine the whole time I owned the mags. I even hand propped it once.

To your other point about EI's requiring a "decent sized" battery - I can tell you for a fact that I measured the SDS CPI current draw at 1.69 amps at full power on a 6 banger. Thats right up there with nav lights. It would not take much of a battery to significantly outlast your fuel supply.

As for disassembling the baffles to check timing with an automotive timing light - that has not been my experience on several EI installations. One can generally fabricate a pointer from a piece of welding rod or other wire, attach it to any convenient screw on the engine, and mark the flywheel with a Sharpie in a few minutes. No need to lean over an engine or get anywhere near a spinning prop - put the timing mark where YOU want it!
 
Every ignition system ever designed has the possibility of failing. That is why we traditionally have always used 2 ignition systems. Any system that is not self powering requires a decent sized battery backup. There are no perfect solutions. A friend of mine bought a nearly finished RV8 with the laser system on it. The only way to check timing was with an automotive timing light from the cockpit, with the engine running. All RV’s I have ever seen have seals and baffles over the top of the engine just aft of the starter gear. All that would have to be removed to check the timing, as well a building a pointer to accurately see there the flywheel is. You are also going to need some binoculars to see the marks from the cockpit. I am curious how other systems deal with checking the timing. The EMag’s are super easy to time very precisely. They have advance for lower power settings which improves fuel economy and they are easy to install and time.

I have EI similar to SDS style and timing is very easy. I made a pointer out of alum tubing and it takes about 5 minutes to get it properly clamped to the case in the correct position. I stand next to the engine, but well behind the prop, to get the timing. Helper adjusts timing via computer while I confirm via the light. Whole process takes 15 minutes. I have magnets in the flywheel, so there is NO DRIFT. Set it and forget it. No automagical TDC reset if the MAP pickup gets a puff of air.

If you think you need to take the baffling off to do this, you need help from someone. While this type of system is not a 1 minute timing operation like the Pmag, it has the benefit of not constantly removing it to check for failures and regularly sending it to the manufacturer to replace parts, like cheap bearings. My system draws under 2 amps, so doesn't take a lot of battery capacity to run it for an hour or two.
 
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I use a Craftsman construction laser available cheap from home improvement stores to project a laser line down the upper case split line and flywheel. No baffle removal required. Looks like this.
 

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Every ignition system ever designed has the possibility of failing. That is why we traditionally have always used 2 ignition systems. Any system that is not self powering requires a decent sized battery backup. There are no perfect solutions. A friend of mine bought a nearly finished RV8 with the laser system on it. The only way to check timing was with an automotive timing light from the cockpit, with the engine running. All RV’s I have ever seen have seals and baffles over the top of the engine just aft of the starter gear. All that would have to be removed to check the timing, as well a building a pointer to accurately see there the flywheel is. You are also going to need some binoculars to see the marks from the cockpit. I am curious how other systems deal with checking the timing. The EMag’s are super easy to time very precisely. They have advance for lower power settings which improves fuel economy and they are easy to install and time.

All ignition systems should be confirmed with a timing light. The only one I would trust is a mag.

As far as timing with a light, here is how I did it. Time it off of the prop...
https://vansairforce.net/community/showthread.php?t=181641
 
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I use a Craftsman construction laser available cheap from home improvement stores to project a laser line down the upper case split line and flywheel. No baffle removal required. Looks like this.

The laser is probably a good idea. I used one to line up my wheel pants on my RV10. The problem with the RV8 I did some work on was that the front baffles were higher than the ring gear making it impossible to use a timing light without removing them. It’s not quite as big a problem on my RV10 because the ring gear is bigger, but it would still be a PIA to use a timing light on the rear timing marks. It’s a lot easier to use the front timing marks with a pin stuck in the starter to index where TDC is.
 
It seems to be lost in translation that one does NOT NEED TO SEE the factory timing maks on the ring gear carrier during the dynamic timing process.

Step 1: set the crankshaft to the desired timing position using the factory timing marks (front or rear).
Step 2: fabricate a temporary pointer aligned with ANY CONVENIENT POINT ON THE RING GEAR.
Step 3: Mark the ring gear adjacent to the fabricated pointer with tapes, sharpie, crayon, blood, etc.
Step 4: Attach strobe timing light to fire with #1 cylinder on the ignition system you are trying to verify
Step 5: run engine and verify timing mark aligns with timing pointer - adjust as required
Step 6: remove timing contraption and drink a beer, satisfied with your brilliance.
 
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It seems to be lost in translation that one does NOT NEED TO SEE the factory timing maks on the ring gear carrier during the dynamic timing process.

Step 1: set the crankshaft to the desired timing position using the factory timing marks (front or rear).
Step 2: fabricate a temporary pointer aligned with ANY CONVENIENT POINT ON THE RING GEAR.
Step 3: Mark the ring gear adjacent to the fabricated pointer with tapes, sharpie, crayon, blood, etc.
Step 4: Attach strobe timing light to fire with #1 cylinder on the ignition system you are trying to verify
Step 5: run engine and verify timing mark aligns with timing pointer - adjust as required
Step 6: remove timing contraption and drink a beer, satisfied with your brilliance.

I’m very good at #6. 😁
 
It seems to be lost in translation that one does NOT NEED TO SEE the factory timing maks on the ring gear carrier during the dynamic timing process.

Step 1: set the crankshaft to the desired timing position using the factory timing marks (front or rear).
Step 2: fabricate a temporary pointer aligned with ANY CONVENIENT POINT ON THE RING GEAR.
Step 3: Mark the ring gear adjacent to the fabricated pointer with tapes, sharpie, crayon, blood, etc.
Step 4: Attach strobe timing light to fire with #1 cylinder on the ignition system you are trying to verify
Step 5: run engine and verify timing mark aligns with timing pointer - adjust as required
Step 6: remove timing contraption and drink a beer, satisfied with your brilliance.

Doesn't need to be on the ring gear.. See my post... https://vansairforce.net/community/showpost.php?p=1658279&postcount=88
 
Not true. My Rocket had neither impulse couplers or shower of sparks type booster when I purchased it. Just two raw magnetos. Started fine the whole time I owned the mags. I even hand propped it once.

To your other point about EI's requiring a "decent sized" battery - I can tell you for a fact that I measured the SDS CPI current draw at 1.69 amps at full power on a 6 banger. Thats right up there with nav lights. It would not take much of a battery to significantly outlast your fuel supply.

As for disassembling the baffles to check timing with an automotive timing light - that has not been my experience on several EI installations. One can generally fabricate a pointer from a piece of welding rod or other wire, attach it to any convenient screw on the engine, and mark the flywheel with a Sharpie in a few minutes. No need to lean over an engine or get anywhere near a spinning prop - put the timing mark where YOU want it!

If you have a magnetos without an impulse coupler, they will fire at 20-25 degrees before top dead center, if they fire at all at cranking speed. Assuming that they did fire weakly, you are likely to have the engine kick back from firing to early for such a slow speed. I gave never heard of this working before.
 
For those of you that wish to wax on about the virtues of the ignition system you installed and **** the Emags, please start your own thread. It’s easy enough to do. The purpose of my original post was to share information with others that have 6 cylinder Emags. It was not to start a debate about who makes the best ignition system. Most of us are already quite familiar with the good and bad things about every system out there. Most of us made decisions based on what was important to us.

I appreciate those that have offered information that I did not have. The engineer that mentioned the possible problem with fatigue from vibration is quite possibly right. I am still looking into possible causes. As far as I know I am the only one that has as seen this so far.
 
If you have a magnetos without an impulse coupler, they will fire at 20-25 degrees before top dead center, if they fire at all at cranking speed. Assuming that they did fire weakly, you are likely to have the engine kick back from firing to early for such a slow speed. I gave never heard of this working before.

Well now you have heard of it working. As I said, my Rocket mags did fire at cranking speeds no problem. My 320 on my PA-22 had two straight mags for a while and likewise had no problem starting, even hand propping. And finally, my Taylorcraft (hand prop ONLY) has two straight mags, no impulse couplers. For the last 83 years it starts just fine.

This propensity for the engine to roar to life unexpectedly is why we are all cautioned to respect the propeller at all times. Despite the troubles some people have geting the engines lit when they WANT to, there are plenty that start unintentionally with a casual repositioning or accidental bump of the blades. Its a real thing.
 
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What Robert said. :)

For those of you that wish to wax on about the virtues of the ignition system you installed and **** the Emags, please start your own thread. It’s easy enough to do. The purpose of my original post was to share information with others that have 6 cylinder Emags. It was not to start a debate about who makes the best ignition system. Most of us are already quite familiar with the good and bad things about every system out there. Most of us made decisions based on what was important to us.

I appreciate those that have offered information that I did not have. The engineer that mentioned the possible problem with fatigue from vibration is quite possibly right. I am still looking into possible causes. As far as I know I am the only one that has as seen this so far.
 
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