Bendix mag timing light questions?

William · #1 07-01-2014, 07:16 PM

Hello all I've got my Bendix mags mounted to the engine and I'm working on synchronizing the 2 together. The mags are part # S4LN-20 and S4LN-21. How do I hook up the buzz box to the mags? I've tried hooking the buzz box directly to the p-leads but to no avail, the buzz box does no buzzing or lighting.

Any ideas what I might be doing wrong?

thanks,
Bill

BobTurner · #2 07-01-2014, 07:59 PM

Is the key turned to 'both'?

#3 07-01-2014, 07:59 PM

Please read instructions for the buzz box. Should be three wires. One to each mag one ground.

#4 07-01-2014, 08:00 PM

Also make sure you don't kill yourself, remove a plug from each cylinder.

cajunwings · #5 07-01-2014, 09:05 PM

Most of the timing boxes buzz when turned on and you can check the lights by touching the leads together. You might have box/battery/contacts trouble. Most also turn on the light when the points open. This seems backwards if you think of the mag as simple circuit with the points being a switch, but correct if you think of the light coming on and the plug firing as the same event.

Don B

RV - 9 Rebuild in Progress

RONSIM · #6 07-02-2014, 04:14 AM

from the Bendix mags and insert an adapter (I use a cutoff plug lead) into the p lead hole -- hook the buzz box leads to those -- works fine on my engine.

William · #7 07-02-2014, 05:54 AM

Quote:

Originally Posted by BobTurner

Is the key turned to 'both'?

Yes the key is on both.

William · #8 07-02-2014, 05:55 AM

Quote:

Originally Posted by paul mosher

Please read instructions for the buzz box. Should be three wires. One to each mag one ground.

I do have the ground clipped on as well to a good engine ground.

William · #9 07-02-2014, 05:55 AM

Quote:

Originally Posted by paul mosher

Also make sure you don't kill yourself, remove a plug from each cylinder.

Thanks Paul: no plugs are installed.

William · #10 07-02-2014, 06:01 AM

Quote:

Originally Posted by cajunwings

Most of the timing boxes buzz when turned on and you can check the lights by touching the leads together. You might have box/battery/contacts trouble. Most also turn on the light when the points open. This seems backwards if you think of the mag as simple circuit with the points being a switch, but correct if you think of the light coming on and the plug firing as the same event.

Don B

RV - 9 Rebuild in Progress

Hmmm. Didn't test the box. I will hook the ground up and touch the left and right alligator clamps together and see if I get any lights or tones. The timing light I'm using is a tp-105.