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boomer
05-18-2003, 08:00 PM
I have a 1969 115hp Johnson has no spark.I checked the wires coming from the power pack to the distrubator and had fraid wires.Found out sensor was loose and chipped.If sensor was bad or not gapped properly would that cause no spark.

joereeves
05-18-2003, 11:26 PM
"Boomer.... Having a bad sensor in a electronic ignition system is like trying to use a standard ignition system with no points. The result is that there would be no spark. I believe (if memory serves me right) that the gap between the sensor and the metal rotor should be .028 . Unplug the sensor and take a reading with a ohm meter across its terminals. Let us know what that reading is.

You can check the powerpack as follows. Should the pack prove to be bad, I do have one left in my remaining stock which I would discount.

(Battery Capacitance Dischage Powerpack Test)
(Various OMC Engines - 1968 to 1972)

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.

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.

Joe"

boomer
05-19-2003, 09:43 PM
I tested the sensors one read 5.0 and the other read 5.2 on a digital ohm meter and both read 1.0 on a different ohm meter.How much would it cost for a new power pack.I have two 115hp motors one is good and the other is not I've been swapping parts off the one and adding to the other.I've checked both power packs and both sensors.

sparky
05-19-2003, 11:31 PM
" test the distributor cap ,rotor and the coil. "

sparky
05-19-2003, 11:32 PM
Does the motor have a "clipper" box ?

boomer
05-20-2003, 07:55 PM
" I found out that the previous owners of this motor had same problems.One tme they would have spark the next time they wouldn't.Do you think changing the whole wiring harness would work.How do you test the distributor cap,rotor and coil.I think it does have a clipper.I'll check the book to see if I can find it. "

jay
05-22-2003, 10:20 AM
" Boomer,

I have the same motor, a couple weeks ago I tried to get her fired up with no luck. There is no spark at all. I replaced the plugs, wires, batt and had the stator checked at a marine shop. Mechanic said it was good. Put it all back together and still won't start. I leave for Calif for 3 weeks, come back get the boat ready to go to the shop. Thought I would try to start it before I took it in, she fired right up and runs good. Go figure, I sure can't explain it. This is the second year in a row it's done that. Anyone have an idea why? "

david gray
06-17-2003, 11:13 AM
I have recently had to trace out a similar problem on a 1969 115HP V4 EVINRUDE(MODEL#115983S).By following the tests in a seloc manual I found a
grounded wire between the power pack and the sensor where it runs through the bracket at the base plate. This might explain the intermittent
nature of your no fire problem.

jay
06-20-2003, 11:24 AM
" David,

I've had this problem for the last 2 years. It seems when the outside temp is warm the motor runs good. When it's cold, no spark! I have a SELOC manual and will run the tests. "