How to tell if a magneto is coupled or not?

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4RNB

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4RNB
I have a new to me experimental, am trying to order some parts to do some work, maybe I will do it, otherwise it will shorten time in shop having things on hand. Magnetos are 660 hrs each, Slick, I think 6350 and 6351.

If I just order new or OH magnetos with those part numbers, do I need to worry at all about if they are impulse coupled or not, or is that something that is consistent with each model number?

If you have special knowledge on the value proposition for new vs OH, please share.
 
6351 is Impulse Coupled

6350: is non-impulse.

Buy new.

​

 
Experimental you say? Consider EMAG. Way easier to time, many in the field.

If staying slick, I have experienced mag failure just 100 hours after overhaul due to coil failure which is not routinely replaced at overhaul I think. Also I hear coil isn't tested hot by all shops. My coil failures only happened when mags were hot; they ran fine when cold.

Coupled mag has spacer:
 
I’ve never met anyone not happy with Aircraft Magneto Services .

Assuming they dealt with them!
 
FORANE said:
Experimental you say? Consider EMAG. Way easier to time, many in the field.

If staying slick, I have experienced mag failure just 100 hours after overhaul due to coil failure which is not routinely replaced at overhaul I think. Also I hear coil isn't tested hot by all shops. My coil failures only happened when mags were hot; they ran fine when cold.

Coupled mag has spacer:
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Yeah, I've been tempted to go that kind of route. But, the plane I sold was a great wisdom generator. I put everything that was the latest greatest on it, did not recover my money in the sale. Also, came to believe that 3/4s of what I put on it ended up being needless. The economics of things just does not work out in my mind.

Perhaps down the road I will change my mind.
 
Clip4 said:
6351 is Impulse Coupled

6350: is non-impulse.

Buy new.

​

Click to expand...
And remember, impulse coupled mags on a 6 cylinder lycoming have a recommended 250 hour service interval.
 
4RNB said:
Yeah, I've been tempted to go that kind of route. But, the plane I sold was a great wisdom generator. I put everything that was the latest greatest on it, did not recover my money in the sale. Also, came to believe that 3/4s of what I put on it ended up being needless. The economics of things just does not work out in my mind.

Perhaps down the road I will change my mind.
Click to expand...
I haven't priced the emag vs a new slick recently but suspect they aren't much different. Also suspect the ongoing maintenance cost of the emag will be less. Did I mention the emag is WAY easier to time?

If you do go slick, I would then consider the g3i harness so you can use auto plugs at $1.50 each new.
https://www.g3ignition.com/magmod.html I was using one of these they made for me on both mags for years. Recently I installed one emag so now I just have the g3i harness on the remaining slick. The one they made is high quality. I even have had A&P's who saw mine comment they liked it.
 
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kyleb said:
And remember, impulse coupled mags on a 6 cylinder lycoming have a recommended 250 hour service interval.
Click to expand...
Not sure why I have to remember this, but at least get it correct. It’s not service, it’s only an inspection. And, it doesn’t apply to all Lycoming 6 cylinder engines.
 
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Any consideration of a SureFly mag?
 
kyleb said:
And remember, impulse coupled mags on a 6 cylinder lycoming have a recommended 250 hour service interval.
Click to expand...

There is an AD that applies to the impulse coupling on magnetos used on the 540, which I’m guessing is what you’re thinking of.
 
mondtster said:
There is an AD that applies to the impulse coupling on magnetos used on the 540, which I’m guessing is what you’re thinking of.
Click to expand...
I’m aware of a Slick Service Bulletin-but there could be an AD too. Point is, the OP needs to be aware of the issue and determine the applicability for his situation.
 
If you buy new I suggest that you obtain the Serial Numbers

BEFORE they are shipped. I have found several Slicks that had 3

outstanding Service Bulletins at the time of installation. With s/n

you can go to Slick or Aircraft Magneto Service website to check

applicability BEFORE shipping.
 
kyleb said:
I’m aware of a Slick Service Bulletin-but there could be an AD too. Point is, the OP needs to be aware of the issue and determine the applicability for his situation.
Click to expand...

Absolutely. And ADs do apply to E/AB aircraft so he had better be determining the applicability and adhering to it.

For me, if I had the option I’d be doing a shower of sparks conversion or some sort of electronic system to avoid the impulse coupling trouble on a 540.
 
At least 1 of the referenced SB was pertinent to the Impulse Coupling too!
 
mondtster said:
Absolutely. And ADs do apply to E/AB aircraft so he had better be determining the applicability and adhering to it.

For me, if I had the option I’d be doing a shower of sparks conversion or some sort of electronic system to avoid the impulse coupling trouble on a 540.
Click to expand...
Won't debate whether ADs apply to E-AB or not, but in my mind I think E-AB owners need to be very careful if they choose to ignore ADs simply because they believe they don't have to be adhered to--generally there's a good reason they were issued. Truth in lending, I personally adhere to them as well as any SB's or SI's that apply to my installed systems or the plane itself.

On my 540 I use the Slick Start in conjunction with a Retard Breaker Left Mag.
 
tsts4 said:
Won't debate whether ADs apply to E-AB or not, but in my mind I think E-AB owners need to be very careful if they choose to ignore ADs simply because they believe they don't have to be adhered to--generally there's a good reason they were issued. Truth in lending, I personally adhere to them as well as any SB's or SI's that apply to my installed systems or the plane itself.

On my 540 I use the Slick Start in conjunction with a Retard Breaker Left Mag.
Click to expand...

I agree 100%, especially on the topic at hand. The nice thing about the OP having an E/AB is that there are avenues that could be explored for an alternative solution that might be better than what those with TCd aircraft have available to them. I mainly brought the AD up so the OP was aware that there is one so they’d go looking for it while making a decision on what to do.
 
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