1971 johnson 60hp coil retro-fit

[lastout]

well guys. i tried the retro-fit to an auto coil. bought a universal coil with internal resistor and a condenser with 3 new l77jc4 plugs. the thing actually fired off and ran. idled sweet. took it to the river and idled out fine. opeened it up to run and it quickly became started sputtering and soon died. used a kicker to get back to the ramp. now the motor will kick enough to disengage the starter and immediately die. now heres the run down.: the new coil got hot and i can shake it and feel fluid moving in it. the plugs are firing, but the spark does not seem that intense. fuel pump, carbs, and fuel supply have been checked and are fine.so..... did i do something wrong or do i maybe need a high performance auto coil. i'm ats my whits end. any suggestions would be greatly appreciated. thanks in advance.

 

[Dogger CDN]

Re: 1971 johnson 60hp coil retro-fit

Hi lastout,<br />I have converted my 1970 60hp to the conventional system also. Used it on the weekend for about four hours, and it worked super except that I believe I will open the point gap up to .020" to cure a high speed cutout that I traced to a dwell problem. I am running a universal 12v, internal resistor coil, condensor from 1971 Lincoln 429, and coil is just standard duty.<br />When your motor is running, test the + terminal on your coil. It should read 12-15V. If more than that, you could be having a rectifier problem. If this is fine, what side of coil did you install the condensor? It should be on the - terminal of the coil.<br />If all this checks out, all I can think of to overheat your coil is: coil case not grounded properly,coil is NOT meant to run without external ballast resistor, or excessive coil saturation from too much dwell. Open point gap, and re-time engine.<br />By the way, you will quite often hear fluid sloshing in a good coil also.<br />Let me know how you make out.

 

[binky775]

Re: 1971 johnson 60hp coil retro-fit

if you dont mind me asking,did yours have magneto coils befor converting.i never thought of doing this and i think it would help with firing and maby make it more eficent.

 

[lastout]

Re: 1971 johnson 60hp coil retro-fit

my original system was a dual breaker point w/stator. it has only one coil with a johnson 12 volt amplifier.<br />i will check my incoming voltage when its running if i try this system again. fortunately, i tracked down the guy who owned the boat before me and he had spare parts...lo and behold an old amplifier and coil. put it on and the engine purrs. i'm river testing it tommorow, wish me luck cause if not i'm back to the drawing board. i just can't force myself to put a 300.00 amp on an engine that i have no idea about. i just got this thing. guy gave it to me cause he couldn't make it go. in other words i inherited someone elses headache. i'll let ya'll know how it turns out.