Mag Timing

How to keep the Cessna 170 flying and airworthy.

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N73087

Mag Timing

Post by N73087 »

Is there an easy way to see the timing marks and line them up with the crankcase seam? This is especially difficult with a spinner.
Dave
zero.one.victor
Posts: 2271
Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

I use a little make-up mirror that I bought at the drugstore for a buck to see the marks on the crank flange. I made a little gizmo out of sheet metal that goes up against the edge of the crankcase half ,bends forward,and comes to a point up close to the flange to more easily align the timing mark. It is about an inch wide,as I rcall,and is tapered at one end (on one side only!) to a point. The untapered side lines up with the crankcase seam. The combination of the mirror & the gizmo makes setting the timing pretty easy. Still gotta take the lower cowl off though. :(

Eric
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blueldr
Posts: 4442
Joined: Thu May 02, 2002 3:16 am

Post by blueldr »

The next time you line the crankshaft up on TDC #1, paint a thin black< or contrasting , line on the top center of your cowling and a line on the spinner matching it. Makes it a lot easier. If the cowling is off, match the spinner line to the top case spine split.
BL
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