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1955 evinrude 7.5 spark issues

Mbourquin87

New member
let me start off by saying i dont ask for help unless im pulling my hair out. this ignition system is so simple its crazy, and i cant get it to run. its a 2 stroke lawn mower engine in the water. im losing sleep over this thing. 1955 evinrude fleetwin 7.5 7518. no spark if spark tester is connected to the plug in block. if i run a wire from a head bolt to the tester(light bulb kind) it sparks like crazy. i swear i could spin the flywheel by hand and it would spark that way. cant get it to jump a gap with a plug or a gap tester(its old and rusty, wired wheeled it the best i could) at all. with it all wired correctly, i get a hit on a cylinder every once in a while. ran before i replaced a bunch of stuff, just not well. had a low speed dead miss, had one original coil in it and original wires that were green at the coils. replaced points, condensers, coils twice, wires twice, plugs(i got it with rj12c's in it, put those back in) and rebuilt the carb(not that matters). got aftermarket coils first, they wouldnt go in far enough and hit the flywheel. bought oe coils. bought a cheap set of automotive wires with the oe coils. for a 3.8 chrysler i think. couldnt get any spark. it dawned on me that theres quite a bit of resistance in those automotive wires after it wouldnt spark with oe coils. ordered sierras copper core wire kit and ends. copper core in there now. the plugs arent internally broke. point gap is a tight .020. i have good grounds everywhere. practically no resistance, .1 ohm. coils are flush with the plate boss like they say they should be. flywheel magnet seems strong. im ordering oe j6c plugs hoping the resistor might be screwing with me. it ran before so i hardly doubt thats it. couldnt find coil resistance specs anywhere but theyre brandy new. its almost like the brand new coils are weak. it sparked once or twice with the automotive wires, did i possibly burn up the coils dumping the voltage into a wall of resistance? thinking about throwing the old coils in to see what happens but i got alot of work. annnny help is greatly appreciated!
 
Sorry I pointed it out to you.-----Been working on these simple magnetos for over 50 years.-----Clean those new points.----Set them with a meter and with timing marks on magplate and flywheel.-----See if you get spark.-----Did a 59 5.5 HP for the grandson over the winter.----Set points by eye and got beautiful spark !!
 
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ah, i see. sorry to second guess you. hard to read someone through the computer. clean with scotch brite? 1000 grit? diamond file? can i just fold over a piece of 1000 grit when they're closed and clean them that way? should i clean the spot where the condenser and coil wire mount too? set them with a meter? explain please. i assume you mean multimeter. as far as timing marks, i have the word top on the top of the flyweel with no actual line. there are marks on the mag plate but nothing on the flywheel to line it up with. the word top is on the point cam which is where i set the gap. sort of made sense to me. look, im 33 and never done a set of points in my life lol. im not afraid to say it, i always took them out and put a petronix kit in or a hei distributer haha. much better spark. hei made my 73 buick riviera idle at like 400 rpm. you can about here the individual cylinders fire. sounds awesome. helps that i blueprinted the q jet under the hood too. opened up the air bleeds, relocated the accel pump outlet and straightened the bowls in the ole oven. too poor to afford a holley. that and i also like the mileage and the sound and feel of those secondaries man.
 
Some want to argue.---Are you sure that the green wires are going to the correct set of points ?----Try changing them and see if you get better results.------With the timing mark on the flywheel between the 2 vertical marks on the magplate you set the points to OPEN there.----You tighten the hold down screw first.----Then set points to OPEN with the wee cam screw.-----Hurry and take time to visit -----leroysramblings-------For everything you will need to know.
 
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Throttle position does NOT MATTER !----You are setting the opening of the points for strongest spark.-----Timing relative to piston travel is not a worry for you.
 
so the timing between the contacts and magnet were so far off that by the time the coil fired, most of the voltage was lost. creating a weak spark. if you live within 100 miles of me i'd buy you a case of beer man.
 
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