"Dick" wrote in message
m...
Please, need some advice.

The plane is an experimental homebuilt with a
C-85 engine and 2 new factory overhauled Bendix S4LN-21 mags, each with
impulse couplings and to be timed at 30 & 28 degrees BTC.

Have been trying to install and time mags in acordance with TCM MSB94-8A.
Basically: Ignition wires disconnected and top plugs out of engine; then
to TDC on compression stroke, prop mounted degree wheel to 30 btc for left
mag after unloading the impulse coupling, red tooth of plastic gear
positioned in center of mag access hole (temporarily restrained so as not
to move while installing mag); same for right mag at 28 degrees; remove
temp restrainer plug; hook up "Inductor" (dual mag synchronizer with
four phase audio signal and two LED's); upon hookup, find LED's off and
continuous tone which means the points are open; then try to rotate mag
to a position where points are closed and LED's on........tried many, many
times to get points to open at specified timing BTC!

my problems a
1. Can't turn prop slow enough to get anything other than a very quick
LEDs blip-blip (on-off). I would have thought the points would be closed
for a longer duration..?
2. Can't get enough "travel" on rotating the mags.
3. Have never done a mag installation
before G.

Any help would be appreciated, Dick

PS-I have the Continental engine manual and read and reread the mag
installation section.



Also make sure that the mag switches are "hot" (not grounded) or the P leads
are disconnected.

J. Severyn