I've worked on Wico mags, used on stationary engines. Le Roy hand crank start 4 cylinder engines use an impulse mag. Rather fiddly to reassemble, but doable. Thanks for the great video.
Excellent educational content for those of us that don't learn very well from a book. Thank you for spending the time to show exactly how it all functions.
We examined an engine one year where a set screw had come loose inside. It was a fresh field overhaul and apparently someone forgot to locktite it or tighten it sufficiently. That tiny part went around inside the case for about two minutes--long enough for one circuit of the pattern--and caused a lot of havoc, and by the time they got it back on the runway the crankshaft had broken.
Back in the day I did IFR training on Aztec aircraft. My boss changed the Mags every 500 hours. He sad 650 hours was full life for a mag. Needles to say the company I worked for had excellent maintenance. I did a lot of training in actual IMC.
Some people do advocate replacing them regularly, I know of some companies who give slick mags just one 500 hour IRAN and replace every thousand hours. Bendix mags are pretty robust though and all the parts seem to be readily available at the moment.
Hi - sorry for the late reply, unfortunately I can't take on any work outside of our own fleet of aircraft at the moment, due to pressure of work and certification limitations.
A few thoughts: First off, I applaud your attention to detail, and recognition of it’s importance. Secondly, I am reminded of the recent loss of the B-17. There are but few remaining, and people were killed as well. It seems that a flippant and cavalier attitude towards mags was a primary factor in the crash. Third, I am shocked to see that the impulse coupling does not have a positive snap action between low speed impulsing and direct at running speed. Most centrifugal mechanisms are designed to snap over center for a positive action. That partial grabbing and banging of the mechanism is cringeworthy.
Yeah, it's very old tech, the impulse should. stop operating completely by 450 RPM on most 4 cylinder mags. Engine idle speed should be around 650, so it should only clatter for a few seconds on startup, but like you say - a bad start followed by low idle results in a lot of torture for the components!
Great video! At what RPM should the impulse coupling be disengaged? After start up, i still hear the clicking while the engine is at idle. The clicking doesn't stop until I'm above about 800 to 900rpm. Is this normal??
If you have Slick or Bendix mags on a Continental or Lycoming engine, there should be no impulse coupling operation over 300-400 RPM. If you think the impulse coupling is operating above this range it needs urgent investigation.
I glad I come on to RUclips,,I will like to know if it's possible for me to send 3 wico A series and 3 wipac cj magneto for you to timing and fixes others areas for me can't find no one in st Vincent nor the Caribbean to service them for me thanks for your generous cooperation,
it seems weird to me that aircraft engines still run mags instead of a more modern computer controlled set up with twin ECUs for redundancy as it would reduce the mantanance cost over the lifetime of the engine EFI they used more commonly available automotive parts that have been proven to run for prolonged periods of time. the only benifit i can see with mags is they can opperate without external power but what are the chances of a twin set of alternators going bad in comparison to a mag?
It's coming, for homebuilt and experimental aircraft there are electronic ignition systems available now, including "p" mags, which require electrical power only for starting, then they can sustain themselves once the engine is running, they still have rotors and bearings, but no old fashioned points, and they can monitor engine parameters to set the spark advance for optimum performance. The pace of change is slow in the aircraft industry, certification is a long expensive process and this means manufacturers often stick with old but proven technology
The accessory cases of smaller piston engines are not isolated, mags are driven directly form the engine crank or camshaft gears. The impulse coupling, stop pins etc share this space. Any failure here will shed bits into the drive train and has been known to stop engines without much warning. We also had an incident with a Slick (now Champion) mag many years ago, where an older type of bearing (now superseded) seized solid in the magneto, spun and started to force the mag drive gear out of mesh with the engine. Fortunately the mag shifted on its mount, the timing was affected enough that the pilot picked up the problem on power check and elected not to take off.
Hi - really sorry for the late reply - it seems comments which youtube considered as replies don't appear in my notifications, or in the I haven't responded section! Unfortunately, although we had magneto overhaul and testing on our exposition - it's for our own fleet only, we cannot issue a form one for components overhauled in house. There are several companies not too far away who can do it for you. Brinkley Aircraft services at Meppershall still do a good job. Nicholson McClaren also do mags. Hope this helps.
Disappointing. You should do this, I won't bore you with this. You should do these inspections, I won't bore you with that. Show what you are suppose to do, show why this is no good, why did you change this, not cheap, give us an idea of how much! This is in poor condition, show us why it is poor and what a good one looks like! Why not show where you found out the internal timing and how to set it not just show a tool.
airplanes and old tractors are the bulk of magneto use today, keep the technology alive. thanks for great instructional video
We need more mechanics like you in Alaska, great video, I particularly liked the impulse coupling demonstration.
Thanks, I guess you need decent maintenance out where you are! Not so many places to make a comfortable forced landing!
I've worked on Wico mags, used on stationary engines. Le Roy hand crank start 4 cylinder engines use an impulse mag. Rather fiddly to reassemble, but doable. Thanks for the great video.
Excellent educational content for those of us that don't learn very well from a book. Thank you for spending the time to show exactly how it all functions.
Glad it was helpful!
hey thanks for posting this! I am in the middle of a mag-mania with my bendix RH....getting a newly overhauled one; your video is very informative
We examined an engine one year where a set screw had come loose inside. It was a fresh field overhaul and apparently someone forgot to locktite it or tighten it sufficiently. That tiny part went around inside the case for about two minutes--long enough for one circuit of the pattern--and caused a lot of havoc, and by the time they got it back on the runway the crankshaft had broken.
What a great video. Very well explained and demonstrated. Wish there was more content like this out there. And yes, mags are always neglected!
Not always...
The impulse coupling is just the most ingenious device ever.
Excellent video, very interesting.
Thank you! 👏👏👏
Great info,. never been into one of these, but always wondered how they get a decent spark out at low rpm without a shower relay.
lovely stuff
Great video
Back in the day I did IFR training on Aztec aircraft. My boss changed the Mags every 500 hours. He sad 650 hours was full life for a mag. Needles to say the company I worked for had excellent maintenance. I did a lot of training in actual IMC.
Some people do advocate replacing them regularly, I know of some companies who give slick mags just one 500 hour IRAN and replace every thousand hours. Bendix mags are pretty robust though and all the parts seem to be readily available at the moment.
I was looking to see ADs on the armature and coil of a Bendix mag.
Brilliant, very useful.
hello, great tutorial video. i have a Magnito that needs overhaul and i was wondering if you would do the job for me please.
Hi - sorry for the late reply, unfortunately I can't take on any work outside of our own fleet of aircraft at the moment, due to pressure of work and certification limitations.
Well if it's shower of sparks, then no pins to worry about, or impulse couplers.
A few thoughts:
First off, I applaud your attention to detail, and recognition of it’s importance.
Secondly, I am reminded of the recent loss of the B-17. There are but few remaining, and people were killed as well. It seems that a flippant and cavalier attitude towards mags was a primary factor in the crash.
Third, I am shocked to see that the impulse coupling does not have a positive snap action between low speed impulsing and direct at running speed. Most centrifugal mechanisms are designed to snap over center for a positive action. That partial grabbing and banging of the mechanism is cringeworthy.
Yeah, it's very old tech, the impulse should. stop operating completely by 450 RPM on most 4 cylinder mags. Engine idle speed should be around 650, so it should only clatter for a few seconds on startup, but like you say - a bad start followed by low idle results in a lot of torture for the components!
Very interesting good video.
Al.
Thanks, Al, looking forward to seeing the wheel balancer up and running!
100+ year old technology…….amazing.
why didn't you show how to check the coil and capacitor? Simple to do and important.
Fair point, will try to get that in another video
Great video! At what RPM should the impulse coupling be disengaged? After start up, i still hear the clicking while the engine is at idle. The clicking doesn't stop until I'm above about 800 to 900rpm. Is this normal??
If you have Slick or Bendix mags on a Continental or Lycoming engine, there should be no impulse coupling operation over 300-400 RPM. If you think the impulse coupling is operating above this range it needs urgent investigation.
Nice video
Thanks
I glad I come on to RUclips,,I will like to know if it's possible for me to send 3 wico A series and 3 wipac cj magneto for you to timing and fixes others areas for me can't find no one in st Vincent nor the Caribbean to service them for me thanks for your generous cooperation,
he should write a book on how to do this type work...very interesting
it seems weird to me that aircraft engines still run mags instead of a more modern computer controlled set up with twin ECUs for redundancy as it would reduce the mantanance cost over the lifetime of the engine EFI they used more commonly available automotive parts that have been proven to run for prolonged periods of time. the only benifit i can see with mags is they can opperate without external power but what are the chances of a twin set of alternators going bad in comparison to a mag?
It's coming, for homebuilt and experimental aircraft there are electronic ignition systems available now, including "p" mags, which require electrical power only for starting, then they can sustain themselves once the engine is running, they still have rotors and bearings, but no old fashioned points, and they can monitor engine parameters to set the spark advance for optimum performance. The pace of change is slow in the aircraft industry, certification is a long expensive process and this means manufacturers often stick with old but proven technology
Can you explain how a magneto can throw bits in the engine?
The accessory cases of smaller piston engines are not isolated, mags are driven directly form the engine crank or camshaft gears. The impulse coupling, stop pins etc share this space. Any failure here will shed bits into the drive train and has been known to stop engines without much warning.
We also had an incident with a Slick (now Champion) mag many years ago, where an older type of bearing (now superseded) seized solid in the magneto, spun and started to force the mag drive gear out of mesh with the engine. Fortunately the mag shifted on its mount, the timing was affected enough that the pilot picked up the problem on power check and elected not to take off.
You sound British. Where are you based?
Yup British, we're based in Suffolk
@@framavia2201 I have a bendix 1200 serious magneto that requires overhaul. I’m based at Stapleford. Where is your shop? How can I find you?
Hi - really sorry for the late reply - it seems comments which youtube considered as replies don't appear in my notifications, or in the I haven't responded section! Unfortunately, although we had magneto overhaul and testing on our exposition - it's for our own fleet only, we cannot issue a form one for components overhauled in house. There are several companies not too far away who can do it for you. Brinkley Aircraft services at Meppershall still do a good job. Nicholson McClaren also do mags. Hope this helps.
This poor stop pin :)
They could get me the manual for overjual of these magnetos .. if they had it in Spanish, much better
I am going to thank you very much .. Mexican
Or just get rid of this technology and use FADEC like modern jet engines, heck even ICE cars have this. Leave Mags on lawnmowers.
Disappointing. You should do this, I won't bore you with this. You should do these inspections, I won't bore you with that. Show what you are suppose to do, show why this is no good, why did you change this, not cheap, give us an idea of how much! This is in poor condition, show us why it is poor and what a good one looks like! Why not show where you found out the internal timing and how to set it not just show a tool.
Bore me with the details.