Winning the battle vs the ballast resistor 88 g54b ignition coil wiring

I'm posting this in the hopes that someone benefits. I maybe wrong about something so I encourage and welcome corrections and feedback.

First, hit the over 216 manuals thread and study. I mean really study. Its by far the most valuable resource you have at your disposal.

Second, the haynes manual is trash for figuring out how to wire the ballast resistor. There are some good things to be found in the Haynes manual, but the inconsistencies, lack of necessary information and the fact that a power lock circuit wiring diagram was included while an ignition circuit diagram was not, make it usable as little more than a great way to familiarize oneself with the basics.

The best part of the haynes manual is the fact that all engines are covered, save the astron 2.0, 4g52.

I can't say for certain that this information will be true for those who do not own a g54b. My experience with my 88 led me to the electrical systems service manual from 87 for the montero found in the 216 manuals section. Meep that in mind

In another post someone stated that that MSD Blaster coils are all internally resisted. This is simply not true. I picked up a blaster 2 from a rampage at the junkyard for 10 bucks. It was a P/N 8202. 8203 has an internal ballast resistor. 8202 does not and MSD says to install a 0.8 ohm resistor or resistor wiring when using with a point style setup. The stock/ oem ballast resistor in the truck is 1.1 -1.45. Most measure around 1.35. I Dont have a points style ignition and when the 0.8 ohm resistor cracked i swapped in a stock one and it runs fine. It also ran fine with no resistor until it burned out the little back half-moon on the advance plate inside the distributor. Multiple sources call it different things and it is in reality a combo of them all. It is the pickup coil/igniter/ICM all in one. Don't let them confuse you. If you don't have a resistor I'll wager that you'll burn up multiple of these up many times before the coil suffers any real damage.

If the resistor has only cracked wrap some electrical tape around it and order a new one. Keep driving to a minimum and you should be able to make it to the store and back.

The #1 thing to keep in mind: The ballast resistors are old and porcelain. They are FRAGILE. To remove the presumably 8mm nut on either post make sure you use a second wrench to hold the 2nd nut of the same post or you will crack and break it before you ever get the wire you want. Its very easy to go from excited to install a new coil to frustrated that you now need a part most stores don't carry and you may not be able to drive without.

If you want to preserve your coil, ballast resistor and distributor components, when not running, off or acc are the only places the key should rest. Anything past ACC while the engine is not running will cause the resistor and coil to get very hot and potentially fail.

The way the ballast resistor and coil are wired is simple enough.

There are 2 12v wires coming from the ignition switch. 1 is B&W, the other Black and Red. They hook up to different ends of the resistor. The B&R usually has a female connector and slips onto a male tab connected to one of the posts on the resistor. If you want, you can do away with the tabs and attach it with a ring connector.

99% OF THE TIME IN THESE TRUCKS B&W IS SWITCHED 12V. This should be the case here. The B&R wire only receives power when the key is moved to START. Because the coil needs more power during starting the resistor is bypassed.

FROM THE SAME SIDE OF THE RESISTOR AS THE B&R 12v connect a wire to the coil (+). This allows power to flow directly into the primary winding of the coil unimpeded during only the starting process.

FROM THE SAME SIDE OF THE RESISTOR AS THE B&W 12v connect the B&W wire from the distributor. When the key has been moved back from START to RUN/ON, the B&R 12v is a dead wire. The path of energy to the coil now travels from the B&W THROUGH THE BALLAST RESISTOR and into the coil.

The blue wire from the distributor connects to the (-) terminal of the coil and is involved in signaling the coil to fire. This comes from the 12v supplied to the pickup coil/igniter/ICM via the B&W wire of the distributor. As the signal rotor/reluctor moves it makes and breaks the connection and this is what dictates when the signal to fire is sent by the blue wire to the coil. The coil then discharges via the secondary winding and sends high voltage blasts to the distributor.

There are 2 other things that get wired in as well.

1 is a tiny black noise suppressor to help the radio not pickup the magnetic field generated by the ignition system.. It has a blue wire that also goes to the coil (-) and a black wire that clips it into a series of other clips and grounds. This is not needed to start or run.

The second thing is an inductive filter which is necessary for the tachometer to work but not necessary for the engine to start or run. It connects to the coil (-) and has a second wire with a clip.

The MSD BLASTER 2 8202 should not need the ballast resistor to run. Not because it has an internal ballast resistor (again it doesn't 8203 does), but because most of these trucks use basic and early but still electronic distributors and not points. The MSD may not like the trucks stock resistor.

If you want to do away with the resistor just run the B&W 12v to the coil (+) and the B&W dizzy wire to the same post. The B&W is switched and has power both in the run and start positions. The B&R can be cut, shrink wrapped, and tucked away.

I hope this helps at least 1 person because wiring this thing was a nightmare to understand at 1st mostly because I didn't understand the flow of energy that was meant to be achieved. Just keep the notion in your mind that only one wire is actually sending power THROUGH that resistor and its the B&W 12v from the ignition switch, and only one wire makes use of that modified voltage and its the subsequent wire on the other end of the resistor going to the coil (+)

Great write-up, but I gather the noise suppressor blue wire should go to the coil (+) side, not the (-) as you put it? That's how mine came wired when I got it, tho' that wiring was a bit janky from the PO, so I checked other articles about coil noise suppressors and found they're wired to the coil (+) terminal; in my case, it was attached to the same terminal on the resistor as the B/W wires (not the B/R wire).

“ FROM THE SAME SIDE OF THE RESISTOR AS THE B&R 12v connect a wire to the coil (+).” What gauge should I use? I have 16 on it but have yet to attempt to start it as I’m still working out other stuff

16 ga. wire should be plenty fine; mine came with a wire already attached I'm pretty sure is smaller than that.

Wait is that the black wire with the white heat shrink? Cause if so I wired it backwards

Can you clear this up for me? I got the herko that you recommended so if you could just tell me what side of the resistor and up or down on the coil which one is negative and which are positive? I didn’t see any markings. Also I owe you some wobbly sodas just for helping me so much already. Every day it seems like I do something stupid with this so it’ll be a miracle if it starts in the first place

Huh, mine came with that wire already hooked up, but anyway, the (+) terminal on the coil should be the lower one closer to the mounting bracket, and the (-) terminal should be the upper one.

That short jumper wire connects the (+) terminal on the coil to one end of the resistor (the white ceramic block). That same terminal on the resistor also gets the black/red wire, and that's it for that terminal.

The other end of the resistor gets all the black/white wires, and the blue wire from the noise suppressor (if you have one, a little black box or metal cylinder component with a tab that slips under one of the coil mounting bracket bolts).

The (-) terminal on the coil gets the blue wire from the ICM in your distributor, and the white wire that triggers your tach.

Yeah i had wired it in backwards, thank you so much lol

Does anyone have pictures of an 86 2.6 ignition wiring that's unmolested/modified? It would be so much help as I'm still losing the battle of getting spark to my coil. Thanks in advance

Reckon the '86 should be similar to my '87 setup pictured here:

http://www.mightyram50.net/vbulletin...id=27139&stc=1

That bottom right wire is the one from the center of the distributor? I don't think mine was to the ballast ever, but I'll give it a try laced up like that if so. Thanks man

Not sure which wire you mean? The high-voltage main coil lead to the distributor center terminal is just out of frame at the right edge (you can see some of the boot on it there). The hose with blue and black/white wires coming out of it from top-left is from the ICM inside the distributor. The blue booted terminal at lower-left is one of the black/white wires, which all connect to that end of the ballast.

The white wire goes to the tach. The black/red wire (with the burnt-looking terminal on it here) goes to one end of the ballast resistor, which also has a black jumper wire to the (+) terminal on the coil. That leaves one more set of blue and black wires from the noise-suppressing condenser (little black box visible just above the ballast), where the black goes to a ground, and the blue wire goes to the same ballast terminal with the black/white wires.

Note this is an aftermarket Herko B108 coil, and I dis/reassembled the mounting bracket to flip the coil around for easier wire routing. Not sure if a stock coil would have the coil +/- terminals oriented the same way, so check for any markings on yours.

Thanks for the info. Mine is the first gen (early 86) and is much different than your style though.

What if I don't have a black and red from my ignition? I have a blue(accessory) , black(battery), black and white(ignition) and a black and yellow( in the center unlabled) in told mine is the Japanese version having intake on the driver's side. I'd post pictures but I can't get them to upload.

Wire colors might change from the ignition switch pigtail to the ones underhood you'd connect to the coil/resistor. Colors referenced above are at the underhood end.

At any rate, you should have one wire there that's only hot when the key is in the Run (not just Acc) position, which would be equivalent to the black+white wire described above, and another that's only hot when in the Start position, which would be equivalent to the black+red wire.

The previous owner swapped the motor for the same one. I noticed today that 3 of the wires from the ignition are spliced into one before going through the fire wall into the engine bay. From what I gather they should all be separate or am I wrong? I still haven't figured out how to upload jpegs�� or I'd have pics

Quote:

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Originally Posted by oldirtywizard

I noticed today that 3 of the wires from the ignition are spliced into one before going through the fire wall into the engine bay. From what I gather they should all be separate or am I wrong?

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No, you're right; that does sound pretty weird. I'd guess they spliced the Acc and Run wires? Which is okay enough without points ignition I suppose, but what would the 3rd wire be? Maybe for the key-in-ignition door chime? That one's typically wired to a separate switch on the side of the lock cylinder.

If you have a multimeter, or at least an LED or 12v light bulb you could wire up to a battery, you could test for continuity when the key is in different positions. My ignition switch where the wires are soldered on has the following terminal labels cast into the switch body:

IG1: Black/white
IG2: Blue/red
ACC: Blue
R: Black/red
ST: Black/yellow
AM: Black

Ok. I think I understand now. Sorry I'm not much of a motorhead and even less of an electrician lol. Thanks for your time and patience. I have one more question about how the solenoid is wired in with all this. Would it be the b&r and b&y wires?

Going by the terminal label ST, I'd infer the black/yellow wire attached to that energizes the solenoid with the key in the Start position. Apparently these trucks don't use a starter relay.

At first I'd thought terminal R might mean Run, but it could mean Relay, as the earliest models apparently had an R terminal on the starter:

http://www.mightyram50.net/vbulletin...nd+S+Terminals

...which was apparently moved to the ignition switch later. That seems consistent with the black/red wire on that terminal, as a black/red wire connected to the coil side of the ballast resistor bypasses the ballast, to provide a full 12+ VDC to the coil for a stronger spark during initial startup.

So you may just have a truck built early enough (or an early-model ignition switch) that you just need to add an R terminal to your starter solenoid, as the article linked above explains.

So I finally have it laced up correctly, but when I try turning it over, the starter doesn't do anything now and my temp Guage goes right to the red line for some reason. Any ideas what may cause that? I'm about to just take her to a shop��

Huh. Did you maybe cross some wires somewhere? Pegged gauge would suggest the wire to the temp sender is grounded somehow.

Try switching the small wire to the starter solenoid and the temp sensor wire. They are of similar length and color so it’s easy to get them crossed (and I’ve done it).