pertronix points conversion mercruiser 3.0 140 hp

[Mustangman 52]

Do i need to use a different spark plug wires set after a points conversion the stock wires say for points.is there really any difference? I am not sure what wires to order i am working on a older mercruiser 3.0 140 hp serial #3245055 any help would be greatly appreciated.

 

[Jcris]

As long as the existing wire set is in good shape there should be no need to change them. Unless you change the ignition system in some way that increases output to the plugs, 7mm wires are fine. To my knowledge changing from a points based system to an electronic system will only improve how efficiently the plugs receive spark

 

[Starcraft5834]

I concur.. same plug wires are fine. I just converted my 3.0 140 to Pertronix this spring... keep your timing the same.. did you replace the coil too? hotter spark equals more efficient burn.. looking forward to not having to hastle with new points every spring..

 

[Mustangman 52]

No i haven't changed my coil yet a little confusion there.I see its recommended to have a 3 ohm by petronix mine is 1.5 ohms form what i can tell you can use either but with the 3 ohm requiring 12 volts instead of with capacitor switched 6 volts or so that can run on less then 12 volts. if there is a alternator problem with the 3 ohm you are dead in the water is this correct? any opinions on this.i am chasing a higher rpm miss 1600 rpm or so it starts.

 

[stonyloam]

If you went with the Petronix Ignitor II, you should go with the Flamethrower II (0.3 ohm), coil, and run 12 V to both the coil and module. If you got the Ignitor, your stock coil will be OK, you can leave the resistance wire, but you need to run 12 V for the Petronix module.

 

[Mustangman 52]

i am not sure what what set up mine is. I purchased the boat with it installed.any way to tell the difference?

 

[bruceb58]

If you don't change the gap of the plugs, changing the coil does nothing.

 

[KJM]

I was planning on going to an electronic ignition as well this winter on my merc 165 l6. I was looking at a "hot spark" brand kit and was wondering if anyone had tried them or heard anything good or bad?

 

[stonyloam]

i am not sure what what set up mine is. I purchased the boat with it installed.any way to tell the difference?

Take the cap off and look at the color of the module. Pretty sure the Ignitor module is black and the Ignitor II is red. In either case you need to feed 12v directly to the module. Ignitor is 1146A Ignitor II is 91146A you can find instructions here http://www.pertronix.com/support/instructions/

 

[Mustangman 52]

Thank you.ill take a look.

 

[Mustangman 52]

my ignition is pertonix D57-2 i emailed tec support so far no reply you say it needs 12 volts to the igniter mine is connected directly to the coil with a capasitor switched current about 4.6 volts,seems this is supposed to be hooked to a ignition full 12 volts. is this installed wrong?

 

[stonyloam]

That D57-2 is an environmental regulation carb code of some sort. Indicates it meets some sort of emmisions standards. There may be a number stamped on the plate. Anyway black or red? It does sound like it is hooked up wrong. You can pick up 12 V by removing the red wire from the coil and splicing it into the purple wire from the ignition to electric choke connector on the carb. If the wire is too short, use a 12 ga stranded wire to lengthen. If it is black, be careful, if you leave the ignition on the module can be damaged, if red, no problem.

 

[Mustangman 52]

its black.

 

[stonyloam]

Ok, these are the instructions for your Ignitor. Your stock coil will be fine. http://www.pertronix.com/docs/instruction-sheets/1146A Instruction Sheet.pdf Will show you how to make sure everything is hooked up correctly. Good luck.

 

[Mustangman 52]

OK so my igniter is supposed to be getting 12 volts,this seems would explain my miss at higher rpms.one question my motor is a 4 cyl the instructions say i need a minimum 3 ohms my coil is 1.7 ohms when i test it.is my coil ok or do i really need a coil with 3 ohms?

 

[stonyloam]

You get 1.5 ohms from the coil and another 1.5-1.8 ohms from the resistance (purple) wire for a total of about 3 ohms, so you should be fine. The Ignitor is designed to work with the stock coil. The purple ignition wire provides 12v to the electric choke connector so that is a good place to splice in for your 12v. The purple resistance wire should also be atttached to that connector.

 

[Mustangman 52]

Thank you for your patience,I think i got it disconnect the red igniter wire from the coil,And connect it to the purple wire on the choke correct?

 

[stonyloam]

That should do it.

 

[Mustangman 52]

I am waiting on a water flapper mine was gone.then i can start it it well be a few days.hopefully that solved my miss issue.i well post back thanks.