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Slick Magneto Issue

Fearless

Fearless

Well Known Member
I am having an issue with my Slick magneto on the right side of the engine. I start my plane with the left mag which has the impulse coupler on it. After I start the plane and have both magnetos turned on - if I turn off the left mag the engine dies which tells me the right magneto isn't sparking. I thought I had an issue with the wiring but today I disconnected the p-lead and ground wires off the right magneto to make it always hot and started the plane with the left mag. When I turned off the left magneto the engine died. When this issue originally started I pulled the right mag off and checked the spark off plug number 1 with a paperclip and it would show spark. I put the timing pin in the left rotation hole on the right mag and after setting the flywheel to BTDC reinstalled the mag timing it with the buzz/light box. Would an issue with the cap and wires cause it to not work? Is this a timing issue? I pretty much eliminated the wiring to the switch to be the issue. The plane starts right up on the left magneto. The plane has been sitting for months while I try to get this corrected/sorted (my current job situation doesn't allow much time to make it out to the airport).
 
Fearless said:
I put the timing pin in the left rotation hole on the right mag and after setting the flywheel to BTDC reinstalled the mag timing it with the buzz/light box.
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I believe the pin should be in the right alignment hole when timing the right mag. EDIT: Depends on the model number. R for right L for left rotating.

You may have the problem relating to the latest slick SB. If it's in the affected serial # range or had affected parts installed, Champion will fix it for free.
 
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Mike you are correct in that the pin goes into the hole according to the MAG ROTATION LEFT or RIGHT, as stamped on the mag data plate . This pin has nothing to do with the placement of the mag on the engine ie left mag or right mag position. If the mag doesn't have internal issues and you set the mag in place with the #1 cyl at 25 deg BTDC it should be good to go on the non impulse mag .
 
Raymo said:
I believe the pin should be in the right alignment hole when timing the right mag.
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Not my understanding. I believe the mag will tell you whether it is left turning or right turning on the data plate. Whichever way the mag turns, that's the slot you should use for timing. Has nothing to do with whether the mag is mounted on the L or R. I have two left turning mags on my 6A and just replaced both of the distributor gears in conformance with the service bulletin Raymo references.
 
L hole for left rotating magnetos and make sure the pin goes all the way down to its shoulder in the hole. There is a false positive 180* out that can fool you if you a using a drill bit or similar to find the points opening position.

Ed Holyoke
 
You?re sure you were on the compression stroke for #1, not 360 deg off, when you installed/timed it?
 
No wonder Jeff and I couldn't catch you. I always carry a proper tool (sledge) to fix stuff on the go :D


 
I just had the exact same issue, and went through the exact same process. after two days I found that the engine had not been on the compression stroke when we re-installed the mag. The symptom was the same, so the fact that we disconnected the p-lead led us to believe the it was a mag problem when in reality we had two problems: a bad p-lead and a mag 180 degrees out of time.
 
Vlad,

That SUV is parked in front of my hanger. Sorry I missed you guys. Scott's engine is sweet.

In response to the other posts I used the same method to setting the flywall for the right mag for BTDC that I do for the left which is just fine.

Next full day off I can try to time it again and see what results I get then.
 
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Fearless said:
Vlad,
In response to the other posts I used the same method to setting the flywall for the right mag for BTDC that I do for the left which is just fine.
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You didn't quite answer the question: did you verify you were on the #1 compression stroke? Just setting it to the flywheel marks, you have a 50-50 chance of getting it right.
 
FlyingBanker said:
Not my understanding. I believe the mag will tell you whether it is left turning or right turning on the data plate. Whichever way the mag turns, that's the slot you should use for timing. Has nothing to do with whether the mag is mounted on the L or R. I have two left turning mags on my 6A and just replaced both of the distributor gears in conformance with the service bulletin Raymo references.
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Haven't seen that setup before. Good to know.
 
Rite-System

I use the rite system starting with cylinder number 1 on the compression stroke for finding the 25 degrees BTDC for my Lycoming.
 
Fearless said:
I use the rite system starting with cylinder number 1 on the compression stroke for finding the 25 degrees BTDC for my Lycoming.
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Don't know what the rite system is, but will assume you know what a compression stroke is and how to find it (if unsure, research is prudent here). Check again with the paper clip. If the spark is firing the paperclip, but not running the engine, you are either 180 off, as we discussed, timing is WAY off, you got the ignition wires running to the wrong cylinders, or you found a way to get the cap on wrong (mag has an embossed "1" near the #1 terminal), though I don't remember this being possible on a slick.

While possible, it seems quite unlikely that only one plug would fire with the paper clip. That said, your ear should pick up that one cylinder is firing when it dies.

Be sure the disconnected p lead wires are not touching any metal or each other.

Larry
 
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Fearless said:
I use the rite system starting with cylinder number 1 on the compression stroke for finding the 25 degrees BTDC for my Lycoming.
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The Rite System is unnecessary for engines with timing marks on the fly-wheel and adds unwanted complication. Most Lycomings have timing marks on the flywheel on the front and on the back. The front timing marks line up with the little hole on the starter and the rear timing marks line up with the case split on the spine of the engine. I could see how the Rite System would be advantageous on Continentals where use of the "flower pot" and cylinder pin is necessary.

Remove all top plugs. Rotate the prop in the normal direction until you find the compression stroke on #1. Use the timing marks on the flywheel. If prior to reaching 25 BTDC continue turning until 25 BTDC. If past 25 BTDC, rotate prop backwards until well before 25 BTDC and then move forward until 25 BTDC to remove gear lash. Insert magneto with pin inserted in the hole designated on data card L for Left Mag Rotation and R for Right Mag rotation. Then take it from there. If you've never done this before, it would be best to be shown by a competent mechanic. I haven't looked, but I'm sure there has to be plenty of videos on Youtube and most importantly don't forget about the publications by the manufacturers, Lycoming and Slick manuals and SB's. Those should be your primary reference.
 
arffguy said:
Thread drift here. I'm not familiar with this paper clip trick. How is it done?
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I have never used a paper clip, but if you take a plug out with the lead connected, you can ground the plug to the engine via a wire with aligator clips and be able to observe spark activity while the engine is running or spinning via the starter.

Larry
 
Thanks

Thanks for all the feedback. It was the timing all along. Today I got it timed correctly.
 
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