SCCAIT7

Hello friends- This is my first 1st generation car and it happens to be an IT7 racecar. I got the car about 2 weeks ago and have been having problems starting it- I started with the carburator because I thought that it was not getting fuel. I have worked the carb and the engine is now getting fuel I have realized that the real problem is in the ignition system and the orginal wiring harness.

What I would like to do is rewire the whole system so that I do not have to use the key to start/ignite to coils. This is my first experience with this type of system- If someone could please explain how to wire the distributor and coils. There are 4 wires coming out of the distributor- which I assume are the power and signal wires for the coils...exc. However- If someone can please tell me the color coding and such so I can start at my new switch... and be able to lite my ignition system without the key and by a switch.

Any help is greatly appreciated! Thanks for reading- I know its not the easiest topic!

gsl-se addict

iTrader: (3)

This shouldn't be too hard to do. You are right, the wires on the distributor are for signal and power. The wiring is like this:

BY (black w/ yellow stripe) - this is the power wire. This goes to a switched ignition source. The BY wire connects to both coil + terminals, the bottom terminal of each ignitor plug (those things on the distributor), and the condensor on the distributor (silver cylinder on the side of the distributor).

The YG (yellow w/ green stripe) goes from the top terminal of the trailing ignitor (the black box on the distributor closest to the alt) to the - terminal of the trailing coil (the coil closest to the front of the car).

The YL (yellow w/ blue stripe) goes from the top terminal of the leading ignitor (the black box on the front of the distributor) to the - terminal of the leading coil (the coil closest to the rear of the car).

Then you just need to hook up your tach wire. The stock uses another YG wire that connects to the - terminal of the trailing. If you have an aftermarket tach, you can hook to the - terminal of either coil.

That should be it. You can use a switch (25 or 30 amp) with fuse to connect the power wires. Or a switch in conjunction with a relay.

Hope this helps.

Kent

gsl-se addict

iTrader: (3)

I just saw that your profile says that you have a '79. Does it still have the stock distributor (points system)? The info I gave was for a '81-'85 electronic ignition setup. If you still have the points, I would go ahead and switch over to the electronic ignition. It is pretty easy to do. Everything is a direct swap.

Kent

SCCAIT7

Kent,


No- it has been switched over to the electronic distributor. My question now is how do I get 12V to the system...do I have to run two wires from my switch with 12V to each + side of the coils?? Ground???

When I wire this correctly- there should be no reason why I dont have spark right?

gsl-se addict

iTrader: (3)

So are you not getting spark now? Have you checked to see if you are getting power to the coils and ignitors?

If you want to rewire, just follow the wiring how I said. Connect the ignitors to the coils (- terminals). Then have 12v going into your switch and out from the switch you will connect to both coil + terminals, the condensor, and the bottom terminals of the ignitor plugs. That should do it. You could also use a relay to switch the load. Then use a switch in the passenger compartment to energize the relay.

You don't have to worry about grounding anything. The ignitors/condensor will be grounded through their mounting points (the distributor). The coils just need power (+ terminal) and signal from the ignitor (- terminal).

SCCAIT7

Now I am truely frustrated. I have 12V going to my coil... It appears that I am not getting signal... I am going to go tommrow to a local junk yard and get another distributor. With all the parts I got with the car a distributor is not in them...ohh well... Can you please give me instructions on how to install the distributor- My manual does not explain how to set the engine to TDC.

Any other ideas?

gsl-se addict

iTrader: (3)

Neither coil is sparking? Both sides of the coil should be batter voltage when not cranking/running (key in on position). Are your ignitors plugged in (black boxes on distributor)? Unplug the ignitors and check for power on the wiring. Both terminals (top and bottom) should be at 12v or so with the key on engine not running. Did you check the wiring to the coils? The negative terminals should have a YG wire on the trailing coil and a YL wire on the leading. Sometimes an ignitor will go bad (causing loss of spark to one coil). It is pretty rare for both to go bad at the same time, so check wiring before buying any parts.

How are you checking spark? Are you using the coil wires or spark plug wire? If you are using spark plug wires, you could have a bad cap or maybe the rotor is missing . Let us know what you find out.

Kent

SCCAIT7

Kent,

The issue with this car is someone rewired the ignitors and stuff- SO... the color coding does not match so I am working with a test light to determine the hot lead to the ignitor. I have 12V from my switch going to the + side of the coil. Now what I do not know is there are "other" wires going to the negative side of the coil. I think that I am going to start with tommrow is...

the only thing going to the + side of the coil should me 12V switched and the hot for the ignitors.

AND

the only thing going to the - side of the coil should be the ignitor signal wires

Correct?

When I first got the car and started it- I had a plug wire come off the distributor cap and had arc-ing across the coils while the engine was running. This dawned on me about an hour ago that I just might have blown out the ignitors when this happened.

I am checking for spark by pulling the wire off the coil and hoping for the shock of my life!

gsl-se addict

iTrader: (3)

I see. Yes only the 12v switched will be going to coil + (and to the ignitors as well). The - side of the coils will just have the signal wire from the ignitors. Also, the tach will connect to one of the coil - terminals (usually trailing one on the stock setup). The ignitor plugs look like the letter 'T'. The top terminal (horizontal) is the signal (also called the C terminal). This goes to the - coil terminal. The bottom terminal (vertical) is power (switched 12V). This terminal is also called the B terminal.

So top part of the 'T' goes to coil -. The front ignitor is leading (goes to the rear coil). The ignitor closest to the alt is trailing (goes to the front coil). The bottom part of the 'T' is 12V.

SCCAIT7

Thank you so much..if it wasn't 1:10am I would go make this thing run tonight...I dont think the neighbors would like that very much... I will post tommrow morning and let you know.

SCCAIT7

Ok- it appears that I have 12V going to my ignitors...but no spark... Does that mean that the ignitors are bad? I am debating now weather or not to replace the distributor- however my manual is unclear on how to set the engine to TCD and re-time the engine so I am kinda sketchy... is it hard just to replace the internals out of the distributor?

SCCAIT7

Ok- I am now sure that I have 12V at both my coils and the wires leading out to my ignitors- yet I still do not have any spark... Now what?

gsl-se addict

iTrader: (3)

Did you see if you have 12V at both the - and + coil terminals? Both terminals of both ignitors should also see 12v. You can then switch the power off and check continuity between the top part of each ignitor plug and their respective coil (- terminal). That should at least tell you if the wiring is correct. You can also check the resistance of the coils to make sure they are okay (measure across the + and - terminals, power off). The resistance should be like 2 ohms. Check the high tension wires as well. Maybe swap with another set if you have a spare.

If all this checks out, the ignitors are probably shot. You can usually get used ignitors pretty cheap (like $15 or so each) on here or ebay. Maybe get the whole distributor if you can find one cheap.

Putting the distributor in is not hard. First turn the engine so that the first notch on the front pulley lines up with the timing pin. This is close to TDC. Pull the old distributor out. On the new distributor, you will notice a little dimple on the drive gear. Line that dimple up with the mark of the distributor shaft. Now hold the rotor to keep it from turning and slide the distributor in trying to setit so the center of the adjustment slot is near the bolt hole that holds the distributor in place. Put the bolt in just tight enogh so that you can still rotate the distributor, but have resistance. As you put the distributor cap back on, you will notice that the distributor rotor should be pointing to the L1 output. Connect the high tension wires, ignitor plugs, and condensor. Start the engine, let it get to operating temp, set idle (to about 750 or 800 rpm), then set the timing. Turn the distributor so that when you connect the timing light to L1, the first mark on the pulley lines up with the timing pin. Tighten the distributor. Now put the timing light on T1. The second timing mark should line up with the timing pin. If not, the trailing vac advance pot on the outside of the distributor has two screw you can loosen. Slide in and out to advace or retard the trailing ignition until it lines up with the pin.

Good luck.

Kent

SCCAIT7

Ignitors- Done... hummmming again.... Thanks man! If your ever in the Atlanta area- ill buy you a beer!