1969 85hp Starflite, ignition system change???

68glasspar

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I have a 1969 85hp starflite with the dual point, singe coil, distributor cap type of ignition. I have very good spark coming out of the coil(easily jumps 1/2in gap.) but with hardly jump a spark plug gap. I installed what i was told was a NOS cap and rotor and no change.
If i found a few year new donor 85hp Evinrude that utilizes individual coils, is it possible to swap all the ignition and charging system over, from the timing base through stator, flywheel etc.?
 

68glasspar

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I will look tomorrow, but they came with the NOS cap. They screw into the cap i believe
 

racerone

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Part # of the cap is ??----Yes, all the wires screw into the cap.
 

Chris1956

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I had that ign system on my '59 Fat-Fifty. It worked very well. There was an issue, where if the engine overheated the steel rotor shaft would expand slightly, putting a small crack in the rotor. This allowed voltage to leak to ground, killing the spark.

So, if the spark is good out of the coil, but bad at the plugs, check the spark plug wires for resistance which should be zero. If so, maybe the rotor is bad.
 

racerone

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?????----The ignition on a " Fat Fifty "----Was a belt driven , self contained magneto.-----A completely different ignition is found on a 69 model V-4.
 

racerone

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Perhaps a case of " they look the same , but are not " --------And I believe you might have the wrong distributor cap.----Carefully examine this new one and compare to the old one.
 

68glasspar

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I was going by the number given to me from the ebay listing! I will need to pull it apart to verify it. The number on my old cap is p/n 383520
 

racerone

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The 382480 was only used on the 1968 100 HP as far as I know.---They all " appear " to be the same to some E-BAY sellers !!
 

68glasspar

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that 382480 number was wrong on my part! i removed my cap to check the number. My number on the dist. cap is 383520 and 392342 on the rotor.
 

68glasspar

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The 382480 was only used on the 1968 100 HP as far as I know.---They all " appear " to be the same to some E-BAY sellers !!
I think i may have found my problem, or at least another problem. My battery is old and quickly drops to 9.5 volts, So it has a bad cell. I will replace that. But also need to replace my voltage regulator due to crumbling wires. (see pic). Once i get that done i will go back over the spark tests. I may have just had a low voltage problem and an inoperable charging system!
 

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68glasspar

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I got a new battery and voltage regulator installed. I don't have a water hookup where im working on the boat, so i can't run it to see if its charging now. But i still have my ignition spark problem. Spark will jump 3/8 or better on the coil wire, but only jump .095 at the spark plug wires at cranking speed.
The ignition wires are solid core original wires and ohm test less then 1 ohm.
The primary side of the coil also ohms at 1ohm.
The repair manual says the amplifier output is 300 volts to the coil, should the 300 volts be present at cranking speed?
 

68glasspar

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Bad rotor??----Bad cap?
When i had it apart i checked resistance from the contacts of the cap thru to spark plug ends and also from the inside of the rotor to its contact, all ohm less than 1 ohm.
The cap and rotor were replaced with supposedly NOS parts.
To me it seems to have spark but not enough power behind it to jump the gap in the cap and still have power to jump 3/8in at the plugs. So if i have low voltage into the amp will i have low output at the coil?
Where's the mostly likely thing that would cause a low output?
thanks for the help!
 

racerone

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System will make spark when turning flywheel with socket and ratchet wrench.
 

racerone

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???----If coil generates 3/8" spark , you should have spark at the plug boots.----From 1008 miles away I believe there is an issue with cap or rotor.-----Or boots where wires screw into the cap.
 
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