Re: 76 Johnson 135hp.
Regarding your coil problems...<br /><br />I'm not sure exactly what coils the manual refers to but.<br /><br />If the sensor/trigger coils are backwards the plugs will not fire at the right time. Basically cylinders 1/3 and 2/4 will have their timing backwards. You'll still get spark bu not at the right time. Since you've stated the motor has run, this should not be your problem.<br /><br />If the charge coil (part of stator assy.) is backwards I believe the polarity required to operate the CD module will be incorrect. Again since you've been running, I doubt this is a problem.<br /><br />You'd have to try awful hard to get the ignition coils wired backwards. Basically, you'd have to extend the short ground leads and hook them up to the power pack while shorting the existing long leads to ground. Even the most novice tinkerer wouldn't do this.<br /><br />Based on the information you provided it sounds like with enough cranking speed, everything is fine. So, I would suspect the starting circuit. Your suggestion of replacing the cables is a good place to start. Basically making them out of as large a cable and keeping them as short as possible is best. You should also consider repair or replacement of the starter motor. These motors are quite simple. Most auto-electric shops can easily test and rebuild your starter if necessary. If you feel up to it, you might want to give it a once over your self to see if you can improve its performance. To do this, you can disassemble it inspect the brushes (you can sand off the ends to make sure they aren't contaminated or glazed), clean the commutator, ohm out the windings and lube the bearings. The last that may be suspect is the starter solenoid. If it is somewhat resistive, it could be robbing power from the starting circuit. This can be easily checked by running the starter directly off the battery, which basically is bypassing the solenoid completely (just be careful with the sparks that may occur - you may want to rig some sort of high current jumper that will keep sparks away from the battery and fuel). The last thing to check is all connections to the battery, solenoid, starter and block. If any one of these is questionable it will effect your cranking speed. I think covering these bases could solve your problem. I recently revived a '76 '85 hp and it wouldn't even engage the drive when I first tried to crank it. After going through the starting system, as stated, I found positive connecion from the solenoid was in bad shape. Fixing this made a huge difference.<br /><br />I hope this helps.