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ant996
07-22-2008, 02:41 AM
I have a 93 pro star with electronic ignition. i just won't start?
i've checked the fuel and also the spark. now the spark is very weak, is this the problem?
do i need a new amplifier?

TMCNo1
07-22-2008, 06:37 AM
Maybe a new coil.

ant996
07-22-2008, 07:10 AM
have checked the coil and its ok???

Friday
08-01-2008, 12:29 AM
I had the same problem with my 83 that we converted to electronic ignition. First see what voltage you have at the positive lead of your coil with the key turned on. It should be approx. 12V. If thats not present do a serch for 'Voltage Drop' here and it will give you a step by step to solve the problem. When you say the coil is ok, what is the primary resistance? For a 93 I don't think you had a ballast resistor so your coil should have approximately 1.4ohms of resistance.

In my case it turned out that we had a bad ground cable to the engine and one of the guages was shorting out. I only had about 9-10v at the coil.

86mc
08-13-2016, 01:37 PM
Hello:
I have a 86 Mastercraft 351 Indmar with a prestolite Dist. and converted to Pertrontics Electronic Ignition with Flame Thrower coil. At the starter relay have 12+ volts, at the circuit bar near tranny 12+ V going in but exiting the circuit bar is 9.4V therefore at positive side of coil 9.4V. Very weak spark. Any ideas?

Thanks,
Tom

JimN
08-13-2016, 01:58 PM
Hello:
I have a 86 Mastercraft 351 Indmar with a prestolite Dist. and converted to Pertrontics Electronic Ignition with Flame Thrower coil. At the starter relay have 12+ volts, at the circuit bar near tranny 12+ V going in but exiting the circuit bar is 9.4V therefore at positive side of coil 9.4V. Very weak spark. Any ideas?

Thanks,
Tom

Look at the instructions for the electronic ignition and make sure the ballast resistor is needed- the voltage you show is about what it would be if 12VDC hits a typical ballast resistor.

thatsmrmastercraft
08-13-2016, 10:15 PM
If you have the Flamethrower coil with .6 ohm resistance, you most likely don't need the ballast resistor. Jim's advice is spot on as usual. Pertronix customer service is great. If you can't figure out the answer on their site, give them a shout Monday.


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86mc
08-14-2016, 01:42 PM
Thanks for the info.
Where would I find the ballast resistor? Does anyone know where I can find the proper wiring diagram for this boat?

Thanks,
Tom

waterlogged882
08-14-2016, 02:34 PM
Top and rear of the engine. The white rectangle gadget is the resistor. Use a jumper wire to bypass. Not my engine in the photo.

86mc
08-29-2016, 11:59 AM
Hello All:

Just a follow up. I was able to get the engine started with the voltage drop. Seems my issue was to find TDC and be sure the rotor was pointing to #1 plug. Once I did that it started up.
I still have a voltage drop but doesn't seem to matter. I do know that there is no BR inline that I can find. But since it starts I'll stop looking.

Thanks everyone