Logo
FULL SITE MENU

Dva testing a pull start motor

1

1997 Yamaha C30

New member
Hello new to forum. I was wondering how you can do a DVA test on a pull start outboard. All the videos I’ve seen on YouTube and everything I’ve read so far are for electric start motors. Is it possible to pull start it fast enough/enough times to get a proper reading? Any info would help.
 
Pull starting is doing just what a starter motor is doing. Rotating the motor so as to get it started. Voltages will be created.

When the motor is rotated a charge coil will create and send electricity to a capacitor. When the motor is rotated a pulser coil will create electricity and tell the capacitor to send the electricity stored in the capacitor to an ignition coil(s).

A multimeter with a peak voltage reading adapter will indicate the voltages that are created.
 
Thanks for that reply, it’s very helpful. I had some idea of the concept, I was just wondering if the flywheel needed a certain number of revolutions to get an accurate read. In the YouTube videos they seem to crank the motor for 5 seconds or so. I guess pulling the pull starter four or five times would be a similar number of revolutions?
 
My DVA is on order. I had one other question. I had read/heard on a video somewhere that if the charge coil is sending current to the CDI unit and the pulsar coil is not connected to tell the CDI to release the charge to the ignition coil that you can damage the internals of the CDI. When the CDI electronics troubleshooting guide says to DVA test “disconnected” does that mean you have to disconnect the charge coil and the pulse coil at the same time?
 
1997 Yamaha C30 said:
My DVA is on order. I had one other question. I had read/heard on a video somewhere that if the charge coil is sending current to the CDI unit and the pulsar coil is not connected to tell the CDI to release the charge to the ignition coil that you can damage the internals of the CDI. When the CDI electronics troubleshooting guide says to DVA test “disconnected” does that mean you have to disconnect the charge coil and the pulse coil at the same time?
Click to expand...
I would not believe that for a minute. Would mean that every time a pulser coil becomes defective the CDI assembly would be damaged. In the real world that is not happening. And electrically it does not make sense.

Yamaha generally has components tested "loaded" and "unloaded". "loaded" meaning connected and "unloaded" being disconnected. Also with the motor not running and with the motor running.

For instance

 
Back
Top