Coil recommendation? 3.7

boattoy

Petty Officer 2nd Class
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Aug 21, 2010
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116
Took the boat out a again after having fuel delivery issues. Ran fine for about 20 min. Pulled over to the shore to try a different prop. Went to restart and I got plenty of fuel but no spark. It has pertronix and the original coil has a stripped stud so I put an epoxy filled msd marine coil on. Im almost certain its the coil. I re located it to the right a bit closer to the small 90 degree water hose. I didnt think heat would effect the coil but it was almost too hot to touch. what coil do you guys recommend? If I run a factory one can I give it full 12 volts. I eliminated the resistor wire fyi. Should I maybe relocate down closer to the timing cover? I did notice mounting it sideways it vibrates the coil pretty good but thats the reason I bought the one I did
 

stonyloam

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Mar 13, 2009
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Re: Coil recommendation? 3.7

Petronix Flamethrower II, 0.6 ohm (epoxy if you like, but oil should be OK), bypass the resister wire and run full 12V to the coil and Petronix module (red wire) should do it.
 

boattoy

Petty Officer 2nd Class
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Aug 21, 2010
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116
Re: Coil recommendation? 3.7

I swapped out the coil for my original one and it still doesnt fire. with the original coil connected im getting about 10 volts at the coil(12 volts if i disconnect the wires to the coil). I did notice the coil started to get warm after having the key on for prob 20 secs or so while i checked voltages. any ideas?

the coil i have is .7 ohms so it should be fine if your saying i need a .6 ohm coil. Ill go check the voltages with the new msd coil connected
 

Don S

Honorary Moderator Emeritus
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Aug 31, 2004
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62,321
Re: Coil recommendation? 3.7

I swapped out the coil for my original one and it still doesnt fire. with the original coil connected im getting about 10 volts at the coil(12 volts if i disconnect the wires to the coil). I did notice the coil started to get warm after having the key on for prob 20 secs or so while i checked voltages. any ideas?

the coil i have is .7 ohms so it should be fine if your saying i need a .6 ohm coil. Ill go check the voltages with the new msd coil connected

Sounds normal to me.
Probably not your coil causing the problem.

Old glazed over points may be your problem.

Go to this link http://forums.iboats.com/showthread.php?t=288430
Then have a look at 17 and 21.
 

stonyloam

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Mar 13, 2009
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5,827
Re: Coil recommendation? 3.7

The Petronix needs a full 12V to operate properly. Try a temporary `12V lead to the coil + (Petronix red wire).
 

boattoy

Petty Officer 2nd Class
Joined
Aug 21, 2010
Messages
116
Re: Coil recommendation? 3.7

Sounds normal to me.
Probably not your coil causing the problem.

Old glazed over points may be your problem.

Go to this link http://forums.iboats.com/showthread.php?t=288430
Then have a look at 17 and 21.

I no longer have points. I read I might need a coil with somewhere closer to 1.5 ohm internal resistance if i remove the resistor wire(which I did). Maybe ill try hooking back up the wire from the slave to the coil.
 

boattoy

Petty Officer 2nd Class
Joined
Aug 21, 2010
Messages
116
Re: Coil recommendation? 3.7

I think i figured it out. running a .7 ohm coil with the pertronix 1 ignitor prob burned up the module. they recommend the flame thrower one coil which is 1.5 or 3 ohm. the ignitor 2 recommends a flamethrower two .6 ohm coil. ill just order up both so they match and it should be ok. I dont know if i damaged the coil or not so maybe ill keep the msd as a backup. Should i go with the epoxy filled one again or get an oil filled one?
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
Re: Coil recommendation? 3.7

Some folks recommend epoxy for marine and off-road use, but either should work fine.
 
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