Tachometer/igniton/distributor

[3ryce]

You want to buy a tach that uses a voltage pick-up. This will have a wire that connects to the negative terminal of the coil. Most aftermarket tachs are this type. Considering that no new cars have points anymore some aftermarket tachs might not work with a points type ignition system so make sure to choose a tach that very clearly is designed to work with a points type ignition system.

Thanks for the info. Ill make sure to just call the place first and order it that way. I really want a speed hut guage. but in the mean time im going to see if just this 10$ ballast addition will work or not. Im so ready to get to tuning up my carbs!

[3ryce]

Alright, so the 0.8 ohm ballast resistor did not work. I hooked it up just like the pdf file showed. I did some more reading and found out I have a 6 or 7 series. So I believe ill need to pick up I believe 6AL. Ill have to call MSD and double check. But I do have some other question. I got pictures too. But I tore back some taping around the wires. I think part of whats confusing me is the fact that in the haynes manual the wire diagrams show a GW wire going into the ballast and some wiring coming out the other side connecting to a BW wire which is going to the igntion switch. Also Shows a BW wire coming from the positive side of the coil and going to the tach, looks like it loops and turns GW which turns into a GL wire going to the ignition switch. on my wire harness I could find the GW wire till I tore some loom back. What I found was the GW wire. then a BW wire coming off that going to the resistor and then on the other side of the resistor a BW wire going right back to the GW wire where the first BW coming off the GW wire is. That really confuses me. I get that its an inductive loop and current triggered. I probably dont understand it tho.

Ok this shows the GW wire. see how the BW wires connected to it? the other ends of thos go to the resistor. doesnt make sense to me cause I thought that current wants to flow freely and if theres a short cut then its gonna take it. pretty much i think the way its set up doesnt work. Pretty much made the GW wire split into two.

this picture just shows the BW wires that are connected to the GW wire.

this one just shows a solid black wire coming from the loom. it was split into two. one goes to the - neg. side of the coil and the other goes to the point on the dizzy.

all in all i think some wiring is wrong. but i could be wrong cause im not to familiar with this and wiring in general.

[3ryce]

And beermanpete. if i got a voltage pick up tach wouldnt i need to swap out the dizzy too?

[3ryce]

im sure the wiring is right. just doesnt make sense to me how its wired in with the resistor. oh well. however ive been researching the 280zx dizzy conversion and how it works with the tach. so i looked up online at my local jy and located a 280zx 83 and will just spend that money to get the dizzy and e 12 80 thingy and ya. hopefully that solves my problem. have this link here too.http://atlanticz.ca/zclub/techtips/distributor/index.html

[beermanpete]

And beermanpete. if i got a voltage pick up tach wouldnt i need to swap out the dizzy too?

No, the aftermarket tach will work with the stock ignition system. The only modification to the igniton system will be to replace the current pick-up loop with a piece of wire to complete the primary circuit.

[3ryce]

Thanks beermanpete. So i went to the jy and the 280zx was still there. i might try to talk my dad into heling me to get the diff from it. any ways. I pulled the dizzy off of it. its an 83 280zx. the ICM doesnt say e 1280. but it does have the cb points and it looks like it has some other points on the side that say I W. Does that matter? or should i get an e 1280 module? also got an altenator from a 280zx as well non turbo. hopefully that will work.

[3ryce]

And hey beermanpete, would you please look at the pictures i posted and double check the wiring. looking at the link here. http://atlanticz.ca/zclub/techtips/distributor/index.html the way it says its wired seem to be different. but if you look at the wiring diagram. it shows a BW wire coming from the key run position going to the ballast. however if you look at the pictures i posted it looks like its missing. maybe its fine, but ide like a second or third opinion of the wiring. Im the third owner but the second owner had someone in cali that had a shop in mexico where they worked on the car. so idk whats been done to it.

Edited August 2, 2013 by 3ryce

[beermanpete]

I assume you mean the photos in post #14. Your wiring does look like there is a mistake. The black wire going from the coil - to the points (in the distributor) should not have any connections to the wire loom. The splice from the green/white to the black/white looks factory. Where did the green/white wire go in the last pic? The green/white is the starter bypass wire and should connect to the coil + or the coil side of the ballast.

You need to identify the 2 black/white wires. One comes for the ignition switch and will have +12 volts with the key is on. This wire connects to the ballast. The other black/white wires comes from the tach and goes to the coil +. The green/white wire is the starter bypass and only has +12 volts when the the ignition key is in the START position. This wire also runs to the tach and completes the loop up to the tach (the return is the second black/white wire). If you reverse the 2 black/white wires the car will run but the tach won't work and the ballas is out of curcuit so the coil will overheat after a while.

[3ryce]

I assume you mean the photos in post #14. Your wiring does look like there is a mistake. The black wire going from the coil - to the points (in the distributor) should not have any connections to the wire loom. The splice from the green/white to the black/white looks factory. Where did the green/white wire go in the last pic? The green/white is the starter bypass wire and should connect to the coil + or the coil side of the ballast.

You need to identify the 2 black/white wires. One comes for the ignition switch and will have +12 volts with the key is on. This wire connects to the ballast. The other black/white wires comes from the tach and goes to the coil +. The green/white wire is the starter bypass and only has +12 volts when the the ignition key is in the START position. This wire also runs to the tach and completes the loop up to the tach (the return is the second black/white wire). If you reverse the 2 black/white wires the car will run but the tach won't work and the ballas is out of curcuit so the coil will overheat after a while.

Ok ill start with picture one. The wire with the arrow and 1. should only be coming from the -neg side of the coil and going to the points. I need to see where that wire goes to. I thought it looked funny cause the wiring diagram doesnt show it connecting to anything else.

On my post with the pictures post #14 i believe, you asked where did the green wire go. First let me say that i may have had it connected wrong but changing it around didnt change anything, car still started and tach still didnt work. anyways. the GW wire is infact the BW wire #2 and #3. so its like a Y where the stem is GW but the top parts of the Y are BW. that doesnt make sense to me, thos two numbers come from the green wire. That picture was taken before i tore back some more loom to reviel the GW wire. The all BW wire is #1. so pretty much #1 is all BW havent found anything tapped into or from it yet. #2 and #3 go to the GW wire. GW----<BW. I should have taken a further out picture showing more ha. my bad.

[3ryce]

Sp just a little while ago I disconnected the black wire from the harness, now it just goes from the - neg side of the coil to the points on the dizzy. The tach did not work still, which i expected but it didnt change anything either. I have some pictures I am uploading. In these pictures you will see i have changed the coil with another one. Its name and brand are unknown. The guy i got it from said it might or might not be an orginal z coil. but sense the tach still did not work i believe it to not be an orginal z coil.

Anyways here are the pictures, i apologize for the messiness. When i get the 280zx dizzy and install it, and try the dizzy upgrade ill let you all know if the tach starts to work.

another question that poped up, there was a BY wire. this comes from the ignition? well anyways i believe it to be a hot 12+ wire. as i tried to hook it up to the coil and it started with it hooked up. it was just a simple test so right after it started, i turned it off and unhooked the wire from the coil.

Plug that goes to the back of the tach.

Back of the tach

Ignition switch plug

coil and its wiring.

[beermanpete]

Hmm...your photo shows a 3-wire connector for the tach. The early 240Z used a 4-wire tach that used a current pick-up on the positive side of the coil, like the photo on HybridZ in the tach thread you are posting in. If your tach is a 3-wire tach that would explain the extra black wire on the point side of the coil. Why the tach does not work is still uncertain though. Are you sure the tach is getting power, ground, and the signal from the points?

[3ryce]

I have a 6/73 240z, perhaps they changed it over for the later models and so on to the 260z. I have found this post cause when you pointed out that i have a three wire tach i went to good ol google and did a search. this is what i found. Tachometer - Page 3 - Ignition and Electrical - HybridZ

however after reading it i dont think the guy came to a conclusion, or if he did, he didnt post how he solved it. Im going to wait till I do the 280zx dizzy conversion to mess with the tach a little more, however i will hook that black wire i cut back up. ha.

by the way according to autozone they should have the dizzy in on the 6th.

Also beermanpete, THANK YOU FOR HELPING ME WITH THIS!!!! I feel like im on the way to solving this issue. and im going to document it on here for many other to hopefully search and find. I do wonder when they decided to switch the 240z's to three wire? oh well.