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Installing a Pertronix 1146a and Flame Thrower Coil on a '82 Merc 470 2bbl.

wrestling_coach

Contributing Member
I have read the instructions and all the posts I could find on this site and others and I think this is how this should go. The Flame Thrower coil will be a straight swap + for + and - for -. The 1146a Ignitor black wire to - on the Flame Thrower coil. Now the red wire from the 1146a Ignitor. Since there is a resistance wire from the choke to the + post of the Flame Thrower this WOULD NOT be a 12v source of power the Ignitor requires. So I have to go upstream of the resistance wire and attach the red wire to the choke where the lead end of the resistance wire attaches. Does this sound correct?

Dennis
 
Does this sound correct?
Yes as long as the Igniter requires 12 vdc. Tie off and tape the resistance wire out of the way. Use a purple (color code) 16 ga. wire for the 12 vdc source.
 
Thanks for your quick reply. Question. Will this new combo NOT require the resistance wire any longer? This new coil is 3.0 Ohms.

Dennis
 
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Will this new combo NOT require the resistance wire any longer?
Not if it uses 12 vdc. Keep it taped off and put the points and condencer in your boat's tool box. Although Pertronix is a reliable product you may need it someday to get you off the lake...you never know. I think the timing is 10 deg. BTDC.
 
Try not to confuse Ignitor voltage with coil voltage... they may be same... or they may not be same, since each are on separate sides of the system.

If the coil requires a full 12 vdc (some refer to these as "internally resisted") then no ballast resistor is required.
If the coil requires external resistance, then the correct ballast resistor must be used.

Let your Pertronix installation instructions determine the Pertronix Ignitor voltage.


Note: Some look to the Pertronix conversion kit to solve problems that are not solvable by the conversion alone.
Progressive spark advance or worn shaft issues for example.
So make sure that your previous points system problem was NOT due to worn or malfunctioning components.
If your shaft is worn (causing a slight wobble that may have created a change to dwell), and/or your advancing system is not doing what it's suppose to be doing, you'll first want to have this corrected.
The kit alone will not fix this.

I say this because all too often I see guys installing the Pertronix kit thinking that this will solve an issue that is actually an issue with the shaft or advancing system.
A shaft wobble will create a dwell change, or fluxuation to dwell, with the Hall Effect units.
Also, if the mechanical flyweights are not working correctly, the new Ignitor will not do much to improve performance.


.
 
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I just went to there site and reviewed there info

The Flamer thower coil has either 1.5 or 3.0 ohms resistance This means it is INTERNALLY resistered. NO EXTERNAL ballast is needed!!

Therefor what you need to do is cut away the wire harness wrap from the positive side of the coil back. Find the point in the harness where multiple purple wires all connect, ONE wire, the one that goes to the coil (NOT THE CHOKE), find this one and look closely, it will be different from the others. The wire itself is a different material. NOT copper..........
This junction is the INGINITION ON Curcit. You can add a NEW 14 guage purple wire here that will bring a full 12 volts to the coil.
If you have two wires going to the + of the coil make sure the one from the starter solenoid (cranking voltage to the coil) you MUST reconnect this so the ignition will work when cranking. If it does not exist then disreguard.

Once you find this and you are sure ad the new wire, rewrap the harness as it was and as suggested tape off the old/original wire that went to the coil + for potential future use.

With the new wire SOLDER a ring terminal to it and connect to the + of the coil.

DONE!

NOTE: the resistance wire does not come from the choke, It is burried in the harness. The choke gets a full 12 volts DC!!
 
make sure the one from the starter solenoid (cranking voltage to the coil) you MUST reconnect this so the ignition will work when cranking. If it does not exist then disreguard.
Kghost, correct me if wrong here.... the "start by-pass" mentioned above was generally for resisted coil voltage systems.
During cranking the resisted voltage would become even lower, thus potentially giving a weak spark and a No Start!
The "Start By-Pass" circuit momentarily circumvents the resisted coil voltage during cranking only, and we get a good clean start up.

Is this an issue for the OP here whereby a Ballast is not required?
 
Rick

That is why I said IF there are two wires to the + side of the coil. HE should aslo look at the starter and confirm two small wires to the solenoid.
Now if he has the ford starter single terminal then this would be found at the external (Ford type) starter solenoid. Large black with I and S terminals and the mounting base is the ground.

There are two methods used.

With point ignitions MOST use the (I) terminal on the STARTER solenoid. All others use the KEY switch to accomplish the "Cranking" voltage to the coil.

All electronic MERC Thunderbolt and newer use the key switch if am correct. No ballast is needed for cranking/starting.

One thing we must remember, the system is designed for 12 volts, when running above 1500 rpms the charging system typically ouputs 13-14 VDC.

Thus some resistance is needed to maintain the 12vdc so the coil will not overheat.

With the points systems I never understood why they just did not design the entire system to run with what ever voltage was supplied............

Why lessen the voltage to the coil so it wont overheat, Just make the coil work with what ever the electrical system will produce????
 
You guys are really helping me out. Thanks. The Pertronix coil I have is the 3.0 Ohms model. Below is a picture and you can see the two purple wires attached to the + side of the coil. OK 1 is the resistance wire, made of a different material, and 1 is the starter solenoid 12v. I'll cut back the tape on the harness until I reach the junction of these wires. I will cut the resistance wire at this point and add a new wire and run it to the + side of the coil. Then the red wire from the Ignitor can go to the + side of the coil for the full 12v that is required. Sound correct? Thanks. Dennis
Starter pic
jan13008.jpg

DSC02902.jpg
 
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Yes I am. Thanks. Right now I am taking the "if it ain't broke don't fix it" approach. But at the first sign of trouble I'll be on the conversion. Later in the summer here I may just go for it however. On my original post however I'm converting to electronic ignition in an effort to obtain a good solid ignition that can perform at low RPM's for trolling speeds down to 1.5 - 3.5 mph or SOG on the GPS.



Dennis
 
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I would NOT cut back the resistance wire.

I would remove it from the coil and simply tape it off and secure it.


I would find the junction and ADD the wire there and run it to the coil.

Here are two schematics

One is the original style with non standard wire colors,
The second is with standard wire colors.

One difference is TAN (OLD) was changed to Purple with yellow stripe (NEW).
 
OK. Just disconnect resistance wire and tape it off. ADD new 14ga purple wire to + coil post. Connect red ignitor wire to + coil post as well. Got it. You guys are the best.
Dennis
 
kghost, hi there my name is drew w' and i have a 1988 3.7l mercruiser 165hp 224cid 4cyl engine and i just installed the pertronix 1146a ignitor kit along with the 40611 "epoxy filled" 3 ohm coil on the boat today...now with wiring it up the black wire for the module goes to - side on coil, done....the red wire from the module goes to + side of coil, done....now the old coil is 1.5 ohms and has a resistor wire going to the coil with purple and purple yellow both tied in together with a terminal, i took them off together and have not cut anything on them and wont if i dont have to as i have read plenty of these forums and i should just tape it up and secure it for future date if i go back to points again....okay the grey or tan wire was my tach wire and that went to - side of coil and put the nut on both it and the black from the module, done..........now my main question i have is there are two wires attached with one terminal going to the choke, one was flimsyer than the other and i put my digital voltmeters blk lead to engine ground and red lead i poked both wires while my grandpa turned the key to on position without starting it and i received 12volts on both those wires while keeping the black touched to eng ground....okay and the pertronix kit came with instruction to verify if i indeed had a resistor wire so i followed it only after i took the points out and installed the new system and one of those wires the flimsy one got hot so i thought it must be because it was resisted and i added a 3 ohm coil to do the test and was way too much amperage so that must be the one i dont want, so i took the sheath off the other one the stiffer one and soldered a new 10 awg wire to it and ran that to + side of coil.........woom started right up and set the timing just to be sure to what the manual calls for 8 btdc and all is well .... let her run a bit like ten minutes and after killing it i just happen to touch the coil itself and man she was hot, now remember its the epoxy filled one and we did away with the water cooled voltage regulator for a aftermarket alternator conv kit off ebay and all that is fine and dandy but the coil bracket is right next to the valve cover and that area gets hot.......after reading this did i wire it up correctly.......oh the splice is bout three inches from the choke itself or three inches down from that little plastic thingy that attaches to the choke.... i will get u a pic or a youtube vid tomorrow .......thanks for all your help and esp your time.....cheers.........DREW W'
 
kghost, hi there my name is drew w' and i have a 1988 3.7l mercruiser 165hp 224cid 4cyl engine and i just installed the pertronix 1146a ignitor kit along with the 40611 "epoxy filled" 3 ohm coil on the boat today...now with wiring it up the black wire for the module goes to - side on coil, done....the red wire from the module goes to + side of coil, done....now the old coil is 1.5 ohms and has a resistor wire going to the coil with purple and purple yellow both tied in together with a terminal, i took them off together and have not cut anything on them and wont if i dont have to as i have read plenty of these forums and i should just tape it up and secure it for future date if i go back to points again....okay the grey or tan wire was my tach wire and that went to - side of coil and put the nut on both it and the black from the module, done..........now my main question i have is there are two wires attached with one terminal going to the choke, one was flimsyer than the other and i put my digital voltmeters blk lead to engine ground and red lead i poked both wires while my grandpa turned the key to on position without starting it and i received 12volts on both those wires while keeping the black touched to eng ground....okay and the pertronix kit came with instruction to verify if i indeed had a resistor wire so i followed it only after i took the points out and installed the new system and one of those wires the flimsy one got hot so i thought it must be because it was resisted and i added a 3 ohm coil to do the test and was way too much amperage so that must be the one i dont want, so i took the sheath off the other one the stiffer one and soldered a new 10 awg wire to it and ran that to + side of coil.........woom started right up and set the timing just to be sure to what the manual calls for 8 btdc and all is well .... let her run a bit like ten minutes and after killing it i just happen to touch the coil itself and man she was hot, now remember its the epoxy filled one and we did away with the water cooled voltage regulator for a aftermarket alternator conv kit off ebay and all that is fine and dandy but the coil bracket is right next to the valve cover and that area gets hot.......after reading this did i wire it up correctly.......oh the splice is bout three inches from the choke itself or three inches down from that little plastic thingy that attaches to the choke.... i will get u a pic or a youtube vid tomorrow .......thanks for all your help and esp your time.....cheers.........DREW W'

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