Logo
FULL SITE MENU

100hp starflite no spark

W

walker30

New member
"hello.
I have a 1972 100 hp

"hello.
I have a 1972 100 hp starflite with cd ignition.
ok the problem is when it is cranking over there is no fire to the plugs at all. but when i turn the key off and on it fires one time. i have changed the timer base and sensor, still no good. any help is highly welcome because there is a tournament on the way shortly."
 
"(Voltage Drop To Battery

"(Voltage Drop To Battery Capacitance Discharge)
( Pulsepack When Electric Starter Is Engaged)
(J. Reeves)

On the older Battery Capacitance Discharge ignition systems (1968-1972), the electric starter reaches a point, even with a top notch battery, whereas the starter will draw excess voltage/current/whatever which results in a voltage drop to the pulsepack. The cure is to purchase a diode which is capable of handling 12 volts and installing it between the starter terminal of the starter solenoid (NOT the battery cable terminal) and the wiring terminal that supplies voltage to the pulsepack.

The diode must be installed so that the current flows from the starter terminal of the solenoid to the pulsepack... NOT vice versa. When that diode is installed in this manner, when the key is turned to the start position, the voltage that is applied to the starter is also applied directly to the pulsepack via the diode effectively eliminating the voltage drop and energizing the pulsepack with the required voltage needed for its proper operation.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store
********************
(Battery Capacitance Dischage Powerpack Test)
Various OMC Engines - 1968 to 1972)
(J. Reeves)

Purchase a small 12v bulb at your local automotive parts store (the 12v bulb is to look like a flashlight bulb, not a headlight bulb). Solder two wires to that bulb, one to the side of the bulb (ground), and the other to the positive point. You might use a bulb of a somewhat lower voltage to obtain a brighter glow... just a suggestion.

Remove the spark plugs. With the key in the on position, make sure that you have 12v going to the pack at the terminal block (purple wire). Now, connect the ground wire from the bulb to any powerhead ground. Connect the wire from the positive point of that bulb to the powerpack wire that is connected to the coil wire on the terminal board (blue wire).

Crank the engine and observe that bulb closely (CLOSELY!). If that bulb glows even the slightest bit, the powerpack is okay. It may be a very dim glow... just so it glows! If it doesn't glow, the pack has failed.

Keep in mind, that type powerpack (Battery Capacitance Discharge) demands a top notch battery of at least 70 amp hours. Any less will, in time, cause powerpack failure.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"Hey thanks for the quick repl

"Hey thanks for the quick reply, could i get the diode from napa or somewhere like that? and another question. I'm doing the ignition troubleshooting guide by the manual, and for sensor circuit test the ohm scale says 4.0 to 6.0. so i test it and it is 0.5(oh and first multimeter).dont know if im reading it right or not instructions are sketchy. ok ill do your suggestions for diode and bulb test."
 
That year model must absolutel

That year model must absolutely have the electrical plug connected as the pulsepack depends on battery voltage.... key must be on for pulsepack to be energized.
 
Back
Top