no spark from coil

[hullofalottatrouble]

merc 260 5.7 350

i thought it was just a battery thing.. but batteries are fully charged and i still get no spark from the coil.. coil is a new flame thrower II.. it worked prior to what i thought was my batteries going dead..

engine turns over fine.. gauges work...

what am i missing? i know there is a trouble shooting guide to check all the components etc.. but i cant find it in my merc manual..

anybody got some step by step guide to check the ignition system?

ignition checks for coil in my multimeter all check out..

i know don posts a checklist frequently but with the search being the way it is .. i cant find it..

thanks

 

[tystick]

Re: no spark from coil

do you have ignition module?

 

[Don S]

Re: no spark from coil

Year?
Ignition Type? Points, Thunderbolt IV, Thunderbolt V?

 

[hullofalottatrouble]

Re: no spark from coil

1982 pertronix II and flame thrower II

had spark just fine last week.. then no spark..

i thought i just had worn down batteries.. so charged em up and still no spark from coil..

 

[Don S]

Re: no spark from coil

Do you have power TO the + (positive) side of the coil?
If you do, you have Pertronix problems.

 

[hullofalottatrouble]

Re: no spark from coil

Don.. i fully believe i has 12v to the coil.. at least before i start to turn it over.. the wire going to the pos of the coil read 12v on my meter..

i still have my old coil to drop in there but i removed my resistor wire per the pertronix instructions.. i assume ill need to put that bad in for the old coil?

 

[freddyray21]

Re: no spark from coil

shouldn't have to put in the resistor wire with petronix

 

[Don S]

Re: no spark from coil

Let me say that I don't recommend Pertronix to any of my customers. Many of the systems requier the use of the ballast resistor or a resistor wire to keep from burning up the unit.
I don't know what your instructions or troubleshooting guide gives you, but I think a call to Pertronix would be the best thing you could do. All the "I had this happen", and the " I heard that this could happen" and the "My ________ (Fill in the blank) caused the problem is not the way to cure YOUR problem.
Find out from Pertronix how to test your ignition system and test it. Then you will know what went bad.

 

[hullofalottatrouble]

Re: no spark from coil

okay problem fixed..

with the flame thrower II it has an internal resistor so you can bypass the resistor wire.. my 12v from ignition wire was loose.. and disconnected all together.. all working fine now..

one of those nights.. time for a beer

thanks Don and freddy and tystick

 

[JasonR]

Re: no spark from coil

Regardless of a ballist resistor, resistor wire or a resisted coil the Pertronix requires at least 1.5 ohms at the coil so the "neg" lead to the module does not burn up the module. That being said it also requires at least 7 volts to fire. If you have a coil with at least 1.5 ohms resistance then your ok and the coil will not need the ballist resistor to keep it from over heating and failing. The resistance does two things, keeps the coil cool and keeps the module from burning up. By having the resisted coil and the ballist resistor on you are decreasing the voltage to much. This is what I learned resently from this sight and the Pertronix Tech I talked to several times in the last couple of weeks.