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will300
03-11-2011, 06:07 PM
I have a 1987 mc with ford 351. If anyone could post some pics of how your ballast resistor is hooked up it would help me out big time. When i bought the boat it was cracked and not hooked up. It bolts up along with the coil. I just need to know which wire runs through the resistor.

Slinkyredfoot
03-11-2011, 06:58 PM
I have attached a PDF for a basic electrical system schematic for a 351 PC, tried it on a picture but I could not read it clearly. Hope this helps.

j.mccreight@hotmail.com
03-11-2011, 07:09 PM
I have a 1987 mc with ford 351. If anyone could post some pics of how your ballast resistor is hooked up it would help me out big time. When i bought the boat it was cracked and not hooked up. It bolts up along with the coil. I just need to know which wire runs through the resistor.

I thought I already helped with this question? Oh well guess not.:confused:

ahhudgins
03-11-2011, 07:51 PM
I thought I already helped with this question? Oh well guess not.:confused:

I remember this question before, and I thought you did answer it. I will throw my 2 cents in as well.

I used to have an 87 MC and replaced the points with the solid state ignition. Per the installation instructions, the ballast resistor is removed when the points are taken out and the new system is installed. If you remove your distributor cap and the points have been replaced with a solid state pick up, you can throw your ballast resistor away.

If I can remember back to my old Ford days, the ballast resistor is bypassed during engine starting to give full voltage to the coil for a hotter spark. Once the engine is running, the ballast resistor is then put back in the circuit to drop the coil voltage (current also). If you are still running a stock coil and the resistor is removed, it will eventually burn up your coil. If someone has added a high performance coil, it may require that the resistor be removed. First find out why the resistor was removed. But that's just my opinion.

j.mccreight@hotmail.com
03-11-2011, 08:20 PM
Ballast resistors are required for points or elect. Ignition and has nothing to done with the distributor and everything to done with the coil. For this answer hook up the purple wire to one side of resistor and the orange wire from the positive side of coil to the other terminal of the resistor. A black wire from negative side of coil to distributor if you still have points. There are high performance coils out there that do not require a resistor mallory and msd both make them, but for an original or stock replacement its is necessary to use a resistor. U can pm me if you like for more information

j.mccreight@hotmail.com
03-11-2011, 08:26 PM
I remember this question before, and I thought you did answer it. I will throw my 2 cents in as well.

I used to have an 87 MC and replaced the points with the solid state ignition. Per the installation instructions, the ballast resistor is removed when the points are taken out and the new system is installed. If you remove your distributor cap and the points have been replaced with a solid state pick up, you can throw your ballast resistor away.

If I can remember back to my old Ford days, the ballast resistor is bypassed during engine starting to give full voltage to the coil for a hotter spark. Once the engine is running, the ballast resistor is then put back in the circuit to drop the coil voltage (current also). If you are still running a stock coil and the resistor is removed, it will eventually burn up your coil. If someone has added a high performance coil, it may require that the resistor be removed. First find out why the resistor was removed. But that's just my opinion.


Old fords had a dual resistor that worked this way, his tristar uses a single resistor so it is not bypassed while starting. At least thats the way my 89 is hooked up and is a virgin.

Slinkyredfoot
03-11-2011, 08:55 PM
Ya know we can all debate this subject just like we do motor oil, filters, bimini tops and all, the proof is in the wiring diagram.

I converted my boat to pointless ignition a couple of years back. I have updated to a hotter coil, ran the smooth MC with wires hitched to the ballast resistor and diconnected them in trial runs. What I have found, for my boat, it doesn't make a hill of beans difference weather you hook them up or not. This is my situation and maybe not any of yours.

Test and tweek, the boat is not brand new anymore and needs the love, not to mention the motors are so much fun and easy to mess with.

Heck, I am just dealing with carb issues and really trying to figure out how to make my beauty scream louder. .:cool::D;):D:

j.mccreight@hotmail.com
03-11-2011, 09:27 PM
Pcm and indmar might share the 351 but your pcm diagram does not match up how my indmar is wired. I would assume his 87 ts is the same as my 89 ts thats has not been touched. But you know what they say about assuming it usually makes an a$$ out of me. Yours probably has more to do with upgrading the coil than changing to ei.

ahhudgins
03-11-2011, 11:03 PM
I have a 1987 mc with ford 351. If anyone could post some pics of how your ballast resistor is hooked up it would help me out big time. When i bought the boat it was cracked and not hooked up. It bolts up along with the coil. I just need to know which wire runs through the resistor.

I think more information is needed. Does the boat run OK? If so, try to determine if a high performance coil has been added or the ignition has been swapped out. If either has been done, you may not need the resistor. Once again, I understand that the resistor limits the current to the coil, but the conversion kit I installed on my 87 required me to remove the resistor. After my conversation, I ran the boat for few years before I sold it.

If every thing is stock in your boat and the resistor has been removed, there is a risk of the coil over heating.

thatsmrmastercraft
03-11-2011, 11:09 PM
Some of the electronic ignition conversion kits, such as the Pertronix unit require you to keep the ballast resistor in place as long as you are using the original style coil.

skidancin
09-26-2011, 04:05 PM
My '86 powerslot is Indmar. I just replaced my engine block, and am crying to confirm correct wiring between choke, ballast, dist., and coil indeed!