280zx Distributor Upgrade (240z)

[CDL1542]

Hi, 

I have read through and followed the http://atlanticz.ca/zclub/techtips/distributor/index.html instructions numerous times for upgrading the distributor to a 280zx on a 240z and have not been able to get my tach to work at all. I have a 3 ohm coil, 280zx distributor and the car is an 11/70 240z (note that the majority of the instructions are for a 280z). I have spliced the blue/white and the green/white wires together from the harness. The thick black/white tach wire is to the postitive side of the coil and the black wire is to the negative. The black wire from the harness is to the distributor box and there is a new wire going from the positive end of the coil to the distributor box as well. Pictures attached so you can see what I did.

What happens to the orange(yellow?) lead from the harness?

Did I miss something or can someone weigh in on why my tach isn't working?

 

[Kurbycar32]

Is this car running other than the tach?

[siteunseen]

I kept my ceramic resistor and ran a wire across it tying the two together. I'm away from my car now and can't provide a picture for you. 8 (

On the tech tip the 240 wiring diagram is at the bottom the page. I followed that and mine works fine. If no one has put something up when I get. home, I will.

[siteunseen]

I told you wrong, sorry. I ran home and took some pics.

The blue wire goes on the negative side of the coil. Reddish brown on the positive side as well as the blak/white. I got the blue and reddish brown along with the plug of a donor zx.

 

The blue and red go to the plug on the dizzy. The black/white comes off the old dizzy through the harness. I hope that helps but without the wiring diagram I can't say much else.

[CDL1542]

1 hour ago, Kurbycar32 said:

Is this car running other than the tach?

Yes, the car is running but the tach doesn't move at all. The tach did work prior to the zx distributor.

1 hour ago, siteunseen said:

I kept my ceramic resistor and ran a wire across it tying the two together. I'm away from my car now and can't provide a picture for you. 8 (

On the tech tip the 240 wiring diagram is at the bottom the page. I followed that and mine works fine. If no one has put something up when I get. home, I will.

What year is your Z? I don't have a brown wire in mine. What benefit does the condenser offer you over not running one? I have not seen someone use this with an upgraded distributor.

[siteunseen]

That brown and blue wire are coming off the plug that connects to black box on the side of the dizzy.

I thought I had the ceramic resistor still but I was WRONG. I do not have it. It seems like I tried that on one of my zs but apparently I did away with it. I remember the wiring diagram showing it "straight wired" with a jumper wire. If I'm not mistaken the black with white stripe is the tach wire. It was tapped in with the others on the harness that runs down under the radiator and horns.

Mine are 1972s.

[Zed Head]

3 hours ago, CDL1542 said:

. I have spliced the blue/white and the green/white wires together from the harness. The thick black/white tach wire is to the postitive side of the coil and the black wire is to the negative. The black wire from the harness is to the distributor box and there is a new wire going from the positive end of the coil to the distributor box as well. Pictures attached so you can see what I did.

Seems like you're working with more wires than you need to.  The "match box" is just taking the place of the points, so you really only need to deal with the distributor.  The negative side of the coil needs to be attached to one terminal of the match box (not sure how they're labeled), and the positive side needs to stay attached to the black-white wire, but with an extra branch going to the other terminal of the matchbox (the extra power wire to the match box is because the module needs its own power, unlike the points).  And the distributor body itself needs a good ground.  You really shouldn't need to mess with the other wires to get the ZX distributor to work right.

Then, if you want to remove the ballast resistor, you would need to connect other wires together, that also attach to the positive side of the coil.

[siteunseen]

If you can't get it working I could untape mine, open up the wiring dressing tube or whatever it's called and take more pictures. Don't really want to because it's nice looking and hidden pretty good but I like to help people that are trying, and you are. 8^)

Cliff

[CDL1542]

On 2/2/2016 at 5:10 PM, Zed Head said:

Seems like you're working with more wires than you need to.  The "match box" is just taking the place of the points, so you really only need to deal with the distributor.  The negative side of the coil needs to be attached to one terminal of the match box (not sure how they're labeled), and the positive side needs to stay attached to the black-white wire, but with an extra branch going to the other terminal of the matchbox (the extra power wire to the match box is because the module needs its own power, unlike the points).  And the distributor body itself needs a good ground.  You really shouldn't need to mess with the other wires to get the ZX distributor to work right.

Then, if you want to remove the ballast resistor, you would need to connect other wires together, that also attach to the positive side of the coil.

I will give this a shot and report back on it this evening. Does this eliminate a condenser as well? I noticed that siteunseen was running one. If I still need one, what rating should it be?

[Chickenman]

The condenser attached to the coil is just a noise suppression device for better radio reception. Primarily on the AM Band. Not sure on the value, but it's not terribly important. Scrounge one off of any car in the wrecking yard. They'll be close enough.

 

There's one on the alternator as well.

Edited February 9, 2016 by Chickenman

[CDL1542]

5 hours ago, Chickenman said:

The condenser attached to the coil is just a noise suppression device for better radio reception. Primarily on the AM Band. Not sure on the value, but it's not terribly important. Scrounge one off of any car in the wrecking yard. They'll be close enough.

 

There's one on the alternator as well.

Doesn't look like I'll have time tonight but doesn't the condenser aid in minimizing the spark across the points contacts to make them last longer in a points system? Would this translate over to the electronic system by storing and boosting the spark? I don't see how the radio interference is the main concern of the condenser at all.

[Zed Head]

Capacitors (aka condensers in the automotive world) can serve many functions.  RF noise suppression is a common usage.  There's one on most alternators, for example.  The function of the one by the coil on the electronic ignition cars is unclear, although I have an extra one on my car to fix a tachometer problem.  The tachometer won't work without it.  It's not the condenser, it's one of at least two (on the 280Z's), maybe more.  Could be that the 280Z condenser filters electrical noise for the tachometer or maybe even the ECU, for injector pulses.

I wouldn't worry about it, but keep it in mind if you have problems.