coil -should I replace?

[reddog349]

I have had my motor for a couple years now and just noticed 2 of the 3 coils have hairline cracks in them . Should I replace them? Ive been haveing some minor engine flooding and poor gas mileage which I assumed was a carb problem ,could these guys be a culprit as well? <br />The motor is a 1977 70 hp evinrude .

 

[OBJ]

Re: coil -should I replace?

How's the spark reddog? Should jump a 7/16" gap real easy. See any signs of the coils jumping to ground? As a check, pull the hood at night with the engine running and see if you see any sparking around the coils. Make sure the grounds are clean and tight at the coils.<br /><br />Hair line cracks are common but don't neccessarily mean the coil is bad unless they go to ground. If everything checks out OK, paint the crack with a couple layers of liquid tape to help keep moisture out.

 

[BillBallinger]

Re: coil -should I replace?

I may be out of place giving advice, but from using these type of coils on motorcycles operating in close quarters you should at least fill the cracks with clear silicone caulk. You may not see it jumping at idle or even fast in a barrel, but under a stiff load it could. <br /><br />I wipe down the area to be caulked with some rubbing alchohol and let it evaporate, then apply the caulk. I have some that says right on it that it is dielectric, I would not use anything with ferritic or carbon surface content (automotive type) for it would act as a bridge.