Mercruiser 3.0L conversion from points to electronic ignition

eavega

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So after enjoying my 88 Stingray for the last two months, its come time to winterize and think about next season. I read that part of the annual maintenance is doing the points and such, and that sounds like a potential for causing timing issues, especially if it has to be adjusted annually. I was looking for alternatives, and keep coming across Pertronix conversion kits. This sounds like something I would like to do, but I can't find the particular model of my distributor to find the compatible Petronix kit. So, quesitons:

1. is the conversion to electronic ignition worth the hassle?
2. Where can I find the manufacturer/model number of the distributor thats on there already?
3. Does anyone know offhand the correct Petronix application for a 1988 3.0L Mercruiser?

Thanks in advance for any help or information you can provide.

Rgds
 

86 century

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Re: Mercruiser 3.0L conversion from points to electronic ignition

Yes converting to electronic is worth its weight in gold.
It is the first thing I do is take the points out and throw them as far as I can.
 

eavega

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Re: Mercruiser 3.0L conversion from points to electronic ignition

If you have the Delco distributor you need the Petronix 91146A and the Flamethrower II coil 45011 or 45111.

Okay, the Ignitor looks like it would be a match. How do I know which coil I need? The one in the boat now is Part number 32193. Actually, I called Petronix, and they told me I needed 40511, does that sound right?

Thanks
 
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matt167

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Re: Mercruiser 3.0L conversion from points to electronic ignition

Either of those listed will work. 45011 is oil filled and 45111 is epoxy filled. Both are .6 ohm and rated for the Ignitor II
 

eavega

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Re: Mercruiser 3.0L conversion from points to electronic ignition

Either of those listed will work. 45011 is oil filled and 45111 is epoxy filled. Both are .6 ohm and rated for the Ignitor II

So the coil is dependent on the Ignitor? I ask because in the repair manual, the specs on the coil that is there is 1.3 - 1.5 ohm. Sorry for my ignorance, but I am having a little trouble wrapping my brain around how this ignition system works.

Rgds
 

thumpar

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Re: Mercruiser 3.0L conversion from points to electronic ignition

I put a Flame Thrower II coil on mine when I converted to the Ignitor II. I just ran a new wire to bypass the resistor wire.
 

RogersJetboat454

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Re: Mercruiser 3.0L conversion from points to electronic ignition

So the coil is dependent on the Ignitor? I ask because in the repair manual, the specs on the coil that is there is 1.3 - 1.5 ohm. Sorry for my ignorance, but I am having a little trouble wrapping my brain around how this ignition system works.

Rgds

Points style ignition systems depend on some form of resistance to drop the voltage down while running, as to prevent the coil from becoming crispy (overheated). Some points ignitions (usually the older breeds) had and external ballast resistor that accomplished this. Some of the other points ignition systems had a coil that had the resistor built into it. For optimum performance and reliability, you want to match the proper coil with what ever Pertronix is calling for. It doesn't necessarily have to be a pricey Pertronix coil, just one that matches the resistance Pertronix recommends.

While your at it... Make sure your mechanical advance springs and flyweights are not broken or frozen. These are mechanical parts that are prone to wear/breakage, and will throw off your timing advance. If you want to be absolutely sure their in good nick, send the distributor off to a distributor shop to have them and the shaft bushing checked out.
 

matt167

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Re: Mercruiser 3.0L conversion from points to electronic ignition

So the coil is dependent on the Ignitor? I ask because in the repair manual, the specs on the coil that is there is 1.3 - 1.5 ohm. Sorry for my ignorance, but I am having a little trouble wrapping my brain around how this ignition system works.

Rgds

I just typed both P/N's into Summit racing and looked at the specs. primary resistance is .6 ohm. only difference between them is oil or epoxy filled. IIRC the secondary resistance is around 1.5 ohm, but I'd have to go back and check to be sure
 

matt167

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Re: Mercruiser 3.0L conversion from points to electronic ignition

Points style ignition systems depend on some form of resistance to drop the voltage down while running, as to prevent the coil from becoming crispy (overheated). Some points ignitions (usually the older breeds) had and external ballast resistor that accomplished this. Some of the other points ignition systems had a coil that had the resistor built into it. For optimum performance and reliability, you want to match the proper coil with what ever Pertronix is calling for. It doesn't necessarily have to be a pricey Pertronix coil, just one that matches the resistance Pertronix recommends.

While your at it... Make sure your mechanical advance springs and flyweights are not broken or frozen. These are mechanical parts that are prone to wear/breakage, and will throw off your timing advance. If you want to be absolutely sure their in good nick, send the distributor off to a distributor shop to have them and the shaft bushing checked out.

reduced voltage is for the points themselves. Less arc, less burning of the point faces. condenser also reduces the arc while making a contact.
 

stonyloam

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Re: Mercruiser 3.0L conversion from points to electronic ignition

Ok need to take a step back here. There are two type of coils here. One works at a reduced voltage (12V dropped down to 8V or so), and needs a resistor in the circuit to drop the voltage when running. That resistor may either be external (resistor wire in the Mercruiser) 1.5 ohm coil or internal (the 3 ohm coil). the second type is designed to use straight 12V, that is the 0.6 ohm Flamethrower II. What you need is the Ignitor II (91146A) and either of the two Flamethrower II's listed. With the IgnitorII/FlamethrowerII combination you need to feed a full 12V to the coil and the module. You do this by removing the purple resistor wire (that comes from the choke connector, I just taped it and coiled it out of the way) and splice in a stranded wire to the choke wire (solder and liquid tape) and run that wire to the coil +. The red wire from the Petronix module also connects to the coil +. Hope that is not too confusing. Any questions, come on back. Good luck.
 
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