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New Lycoming - P-Mag on Right

mfleming

mfleming

Well Known Member
Patron
Great day - My new Lycoming IO-360-M1B arrives :D

The good news: The box had zero damage and looked pristine. The engine was very well packaged...I'm very pleased.

Confusing news: The P-mag is on the right and a impulse Slick mag is on the left...what where they thinking :confused:

I tried calling Lycoming during the engine build period to ask about this but they're almost impossible to get through too.

I thought an impulse mag would not be needed with the P-Mag.

Does anyone have any insight on the mag/P-mag situation.

To add insult to injury, I put the P-Mag test button by the left mag switch instead of the right. :rolleyes:
 

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P-mag on Right

Magneto Left, P-Mag Right is the normal configuration for a Lycoming engine.

For dual mags, the left mag is impulse, right fixed.

I'm going to put dual P-mags on my new Thunderbolt IO360M1A. Much more reliable and tunable.
 
Sooo....I was originally thinking of selling the Slick and installing a SurFly on the right.

Are the P-Mags interchangeable...meaning, can I switch the P-Mag to the left side?

An Aside...why in the world does Lycoming install an impulse mag when they are installing a P-Mag???
 
Yes you can move the PMAG from the right side of the engine to the left. I’m doing this NOW. (Actually adding a 2nd PMAG on the left side.) You will need shorter studs and a different drive gear to use the PMAG in the left. You can get these from EMAG https://emagair.com/pricing/

EMC65101, $9.50 for a pair
EMA35501, “Cert L Gear” $225

Regards,
 
P-mag on Right

The impulse drive for the magneto retards the timing to near zero advance, the same as the P-Mag. This allows you to start with both ignitions on.
 
mfleming said:
Sooo....I was originally thinking of selling the Slick and installing a SurFly on the right.
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You can still sell the Slick impulse mag and install a SureFly on the left. SureFly sells a version to replace an impulse slick without having to change the mounting studs. You will still need to buy the drive gear for it though.

I'm running a Pmag on the right and a SureFly on the left and start on both.
 
Great Combination

I have that exact combination on a Carbed 0-360A1A and I love it. :D Starts on the first or second blade EVERY time. Runs smooth. The only issue I have ever had is the 500 hour service bulletin on the Slick.

Leave it alone and get flying!:)
 
BillSchlatterer said:
I have that exact combination on a Carbed 0-360A1A and I love it. :D Starts on the first or second blade EVERY time. Runs smooth. The only issue I have ever had is the 500 hour service bulletin on the Slick.

Leave it alone and get flying!:)
Click to expand...

That might just be the best advice I’ve had all day ;)
 
mfleming said:
That might just be the best advice I’ve had all day ;)
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Michael, not trying to scare you as I probably was just one unlucky S.O.B. but check out my thread here involving the impulse coupler destroying itself on a brand new mag and causing me a tremendous amount of grief involving me personally having to change out an idler gear inside the engine.

I will never put an impulse coupler in my engine again. I am not the only person that has been bitten by them failing either...
 
jcarne said:
Michael, not trying to scare you as I probably was just one unlucky S.O.B. but check out my thread here involving the impulse coupler destroying itself on a brand new mag and causing me a tremendous amount of grief involving me personally having to change out an idler gear inside the engine.

I will never put an impulse coupler in my engine again. I am not the only person that has been bitten by them failing either...
Click to expand...

Yes, I was disappointed to see an impulse mag on the new engine. Unneeded complexity with the P-Mag installed.

On the other hand, I've flown behind impulse mags since the early seventies with no problems but I'm still annoyed it was on the new engine...oh well...
 
Your set up is exactly what I asked for. I wanted one conventional mag as I wasn't ready to make the jump to two mags. Having a impulse mag will never be stuck at a remote location due to a dead battery. You have the option to hand prop with impulse mag to get started and then once pmag is operating at its minimum RPM it will generate its own power. At some point I will likely swap it out for a 2nd pmag, perhaps at overhaul of the impulse mag.
 
Lycoming knows what they’er doing.

If you have a dead or very weak battery you can still start the engine by hand propping having the impulse coupled mag. If you have two P-mags hand propping is useless without power to the mags. They don’t start producing there own power till they reach 6 or 7 hundred RPM.
 
Hand prop Pmag

At one point, Pmag claimed a 9 volt smoke alarm battery would start the engine. I have snap on connector in the harness for this purpose. I have not used this feature. So, has anyone tried it ?

After thought, now that I have a 3 blade prop it would be useless.
 
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mfleming said:
Great day - My new Lycoming IO-360-M1B arrives :D


Does anyone have any insight on the mag/P-mag situation.
Click to expand...

I have the exact same configuration. I talked with P-Mag and it advised that I should not wire the jumper in the starter switch with the Slick/P-Mag configuration. In an older dual-magnetos configuration, the jumper disables the right magneto and the engine gets its sparks from the left impulse coupling magneto. In the Slick/P-Mag configuration, by disabling the jumper, both the Slick and P-Mag are set to fire when starting the airplane, hence the starting is much easier with the combination. In addition, the P-Mag is timed to fire the plugs right away instead of a few cycles in order to wind up the impulse coupling. Most of the spark energy and timing are controlled from the P-Mag unit and the impulse coupling magneto is just along for the ride with the added sparks. I haven't started anything yet, just relaying the information from the P-Mag people
 
PhatRV said:
n addition, the P-Mag is timed to fire the plugs right away instead of a few cycles in order to wind up the impulse coupling. Most of the spark energy and timing are controlled from the P-Mag unit and the impulse coupling magneto is just along for the ride with the added sparks. I haven't started anything yet, just relaying the information from the P-Mag people
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First, a mag fires every 180 degrees of rotation, even on the impulse. Depending upon where it stopped, it may miss the first firing event but usually doesn't as it was using the impulse as it shut down. The EI system has to hit TDC at least once before it can fire the next event, so usually requires a full rotation before it starts firing. A mag impulse does not wind up like a watch. If you have ever turned your prop and heard the snap, that is your impulse coupling standing ready to do it's job. Also, the mag is NOT along for the ride, especially when both systems are firing at or near TDC, as is the case during starting. Your engine will start much easier with 2 plugs firing at TDC than just one. I agree that the mag is not contributing a lot when the pmag is at 35 BTDC, but your not there when cranking.

You were given bad data.
 
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