Is electronic conversion a simple drop in?

renken83

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I have an '83 3.0L Merc I/O and the local parts place has an electronic conversion kit. My quick search through the forums brought up a couple questionable mods that might need to be done also? They were newer engines though. Is there anything else I need to do besides switch out the points/condenser and install this thing? I plan on checking timing afterward too.
Thanks!
 

Bondo

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Re: Is electronic conversion a simple drop in?

Ayuh,....

It's sorta plug & play,...
But,...
You'll still need to set the Timing,+ the other usual Tune-Up stuff.....
 

Robj

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Re: Is electronic conversion a simple drop in?

Easy,

Take your points, condensor and ballast resistor and throw them away. Run a full 12 v, ignition switched to the module. You may also want to get a new coil as well. This way you know you have the right coil.

Have a great day,

Rob.
 

mthieme

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Re: Is electronic conversion a simple drop in?

I put one in my 4.3 a few years ago. What a difference. Easier that putting in points (which you can still install if needed).
 

MikDee

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Re: Is electronic conversion a simple drop in?

Not a bad idea, but make sure you follow the directions, because you have to make a small modification for your shift interrupter switch, that momentarily kills the engine as you shift (this normally helps provide a safe smooth shift) I think you just have to add a resistor in the right spot.
 

racerock

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Re: Is electronic conversion a simple drop in?

Check out Pertronix. Have put them in a couple cars, and a friend of mine put it in his Mercruiser. Great stuff, been around for years.
 

Fishermark

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Re: Is electronic conversion a simple drop in?

I also recommend the Pertronix unit - easy to install and very dependable. You do not need to do anything to the shift interupt switch - I believe that only applies to OMC systems, not your Mercruiser. As mentioned above, you will need to bypass the resistor wire (which you have instead of a ballast resistor), and buy a new coil that has internal resistance.

I would recommend the Ignitor II as it offers some considerable advantages over the original Ignitor I.
 

Fishermark

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Re: Is electronic conversion a simple drop in?

By the way, here is a copy of the instructions to show how easy it is:

IgnitorIIinstructions.jpg
 

renken83

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Re: Is electronic conversion a simple drop in?

I also recommend the Pertronix unit - easy to install and very dependable. You do not need to do anything to the shift interupt switch - I believe that only applies to OMC systems, not your Mercruiser. As mentioned above, you will need to bypass the resistor wire (which you have instead of a ballast resistor), and buy a new coil that has internal resistance.

I would recommend the Ignitor II as it offers some considerable advantages over the original Ignitor I.

Thanks all for your responses!
Fishermark, I'm not sure which is the resistor wire, is that the other wire coming into the contact that the points also connect to?
I should also buy a new coil? The sheet you posted says Ignitor II electronic ignition but you also recommended the Pertronix unit:confused:
Can the distributor shaft be turned by hand or do I rotate it some other way?
The local parts place has the electronic module but I'm not sure which brand. I'll see when I get there.

Rob, does bypassing the resistor/ballast wire mean that it's going to be 12v directly to the module or do I run new leads to it?
Go easy on me...I'm just a cadet :)
 

racerock

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Re: Is electronic conversion a simple drop in?

I should also buy a new coil? The sheet you posted says Ignitor II electronic ignition but you also recommended the Pertronix unit:confused:

A friend of mine that converted his two engines on his 60's vintage Magnum with newer engines and his brothers 165 Mercruiser bought the Pertronix coil, and it did not run that great with it. Put the Mercruiser coil on, and it ran much better.

We also talked about the Ignitor II. We came to the conclusion that with our boats, we just wanted the thing to work, not try to get any more performance (Ignitor II has adjustable Dwell to increase spark...) and it has internal electronics to shut itself off if you leave the key on...

Well, we don't leave the key on, and just want a better spark. Engines are bone stock and aging so we did not expect any performance improvement with the Ignitor II - so we agreed that the more basic original Ignitor is our way to go. He had bought a spare to keep in the boat and has never needed it...
 

Fishermark

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Re: Is electronic conversion a simple drop in?

I'm not sure which is the resistor wire, is that the other wire coming into the contact that the points also connect to?

On the positive side of the coil you will have two wires - one comes from the starter and provides a full 12v at starting. The other wire is the resistor wire. You can simply remove it and replace it with a switched 12v power source.


The sheet you posted says Ignitor II electronic ignition but you also recommended the Pertronix unit:confused:

Pertronix is the brand - Ignitor or Ignitor II is the model - both made by Pertronix.

As racerock mentions there are several "upgrades" offered by the Ignitor II over the original. Most will make no difference whatsoever to you and your boat. The ONE that does (or at least can) make a difference is what happens if you accidentally leave your ignition key "on" without the engine running. If that happens you can burn out and ruin the original Ignitor, just as you can burn points. The Ignitor II offers built in protection against that. For me, the little cost difference is worth it as a protection factor.
 

mthieme

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Re: Is electronic conversion a simple drop in?

Mine's an OMC. I had to do nothing but drop in the Pertonix CDI module and wire it to the coil.
 

thumpar

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Re: Is electronic conversion a simple drop in?

I did this conversion on my '83 merc 120 last year. I would recommend going with the ignitor II. The version I will cause problems if you keep the key on. When I did it I went with a pertronix coil also so that I could make the whole setup 12v. I checked the timing after the conversion and it was perfect.

Starting is a bit easier now and I gained 200-300 RPM. Best money spent IMO.
 

Eliminator

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Re: Is electronic conversion a simple drop in?

Been using the Ignitor for many years at work with NO failures except for one where someone sprayed brake cleen in the distributor and the magnets fell out when the tape fell off! The leaving the key on situation would be the same if you had points, and the points were closed. You would cook the coil, burn the points, guess possibility of a fire. Seen a few coils where the tops have popped out of the cans.

Recently installed an ignitor II and more than happy! Only about $30 to $40 more!
 

MikDee

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Re: Is electronic conversion a simple drop in?

Mine's an OMC. I had to do nothing but drop in the Pertonix CDI module and wire it to the coil.
Well, about 10yrs I put the original Pertronics ignitors in my 22'- 86' Celebrity Cuddy SS with twin OMC 4.3-205hp Cobra's, and I had to use a resistor, or capacitor (don't remember exactly which at the time?) for the shift interrupter, and remove the resistor wires (because they're less then 12volts) and run 2 new- 12volt switched lines to the coils for ignition, as per the instructions! Hence the reason for my previous post, I thought Mercruiser required a similar mod? Alas that boat is long gone now :( I don't think I could afford to feed it nowadays anyway :rolleyes:
 

renken83

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Re: Is electronic conversion a simple drop in?

O.k., got it. Pertronix is the make, ignitor or ignitor II is the model. Much easier with part in hand. Turns out the shop had the ignitor model. I asked the owner about my set up and was told my coil would work. I appreciate the recommendations on the Ignitor II but I'm already in the habit of disconnecting the battery (off-set lever type disconnect on the neg. terminal) so I'm not worried about leaving the key on.

According to directions, as long as I don't have the ballast resistor, black wire from the ignitor module goes to - on the coil, red goes to + on the coil. I looked and didn't see the ballast resistor. There is a bit of wiring wrapped in elec. tape that it could be in but it doesn't look like it. I'm going to check the wiring schematic again to double (triple?) check. I did install it but haven't reconnected the battery yet. It was simple. The only "problems" were/are the grommet on the wires from the module was so long that the wires were laying right up against the motor. The cut-out on the distributor happened to be facing the motor and that's where the wiring is suppose to exit since there is already 1/2 of an opening for the grommet. I trimmed the grommet back and there's enough room.

The other "problem" is that I'm not sure how to rotate the distributor shaft to be sure the magnet on the shaft has clearance from the module all the way around??? I can turn it by hand 1/8th of a turn maybe before it catches. I'm assuming I shouldn't put a wrench on it and make it turn...or should I?

Thanks again!!!
 

cgrooves

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Re: Is electronic conversion a simple drop in?

According to directions, as long as I don't have the ballast resistor, black wire from the ignitor module goes to - on the coil, red goes to + on the coil. I looked and didn't see the ballast resistor. There is a bit of wiring wrapped in elec. tape that it could be in but it doesn't look like it. I'm going to check the wiring schematic again to double (triple?) check.

If your coil says something along the lines of "To be used with external resistor", then you should have an external resistor on the boat. If the coil says something along the lines of "Internal resistor", then it is built into the coil. If you can still read the writing on your coil it should be easy to determine what setup you have.

The other "problem" is that I'm not sure how to rotate the distributor shaft to be sure the magnet on the shaft has clearance from the module all the way around??? I can turn it by hand 1/8th of a turn maybe before it catches. I'm assuming I shouldn't put a wrench on it and make it turn...or should I?

When I installed points recently, I just loosened the distributor clamp and was able to rotate the distributor past one lobe and through a flat spot. I set my clearance off of one lobe. Theoretically, you shouldn't have to rotate the shaft 180 degrees since all of the lobes are 'supposed' to be the same.
 

MikDee

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Re: Is electronic conversion a simple drop in?

Ok, I'm doing this from memory, if you have access to a wiring diagram this may help you understand:

On the plus side + small terminal of the coil, you have 2 wires. When you turn on the key, one wire is for ignition only (Run), it is the resistor wire having less then 12volts. This resistor wire Plus + (Run/ignition), goes from the key, thru the shift interrupter (I believe) to the coil, this is the one that needs to be replaced with a switched full 12volts to feed the Pertronics ignitor.

The other wire has a full 12volts for starting/cranking only, energized when you twist the key to crank/start, (it is dead all other times).

On the other side of the coil the negative - terminal, one wire feeds the Tachometer, and one wire feeds the distributor (Run/ignition), irregardless of the coils incoming voltage, (don't touch these).

I hope this is clear enough? Good luck, Mike
 

renken83

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Re: Is electronic conversion a simple drop in?

Yep, it is printed on the coil to be used with an external resistor.

MikDee, yes that is quite clear but (oh man do I feel like a newb!) what is a 12V switched line? Do I just splice into the 12v line before the ballast? Looks like I'm going to have to cut a bunch of electrical tape to find the ballast or at least trace the correct line back far enough.
 

MikDee

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Re: Is electronic conversion a simple drop in?

Yep, it is printed on the coil to be used with an external resistor.

MikDee, yes that is quite clear but (oh man do I feel like a newb!) what is a 12V switched line? Do I just splice into the 12v line before the ballast? Looks like I'm going to have to cut a bunch of electrical tape to find the ballast or at least trace the correct line back far enough.

One of the WIRES ITSELF going into the coil is usually the resistor!

(its usually color coded on a wiring diagram) I THINK its purple, or purple/yellow.

A 12volt switched line that works off the key, is what you'll need to turn your motor on, & off, to replace THAT resistor wire!

You may be able to use a 12volt electric choke wire, But that may bypass your shift interrupter (S.I.) - (not advisable!), unless you run it through your S.I., I think that has a microswitch in it that can handle the straight 12volt power.

It all depends, maybe the power going thru the S.I. is a full 12volts, and the resistor wire just goes from the S.I. to the coil? (take a long close look) Then all you have to do is replace that one short piece of wire with any wire of the correct gauge (thickness) and you will have a full switched 12volts to the coil, and you're done!

By the way, your coil is fine, you don't want a resistor in the system anywhere, so your coil can deliver the full 12volts.
 
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