Jump to content
HybridZ
damesta

Help with ignition on barn find 72' 240z

Recommended Posts

Hey guys, trying to get this barn find to fire, hasn't ran since 98 from what I was told but looks like someone messed with it and tried to start it more recently. Turns smooth and compression is around 130 all the way across, have fuel but no spark. So I'm trying to narrow down the problem and potentially upgrade to electronic ignition at the same time. First issue is I have is wiring in the distributor/coil/transistor are...this has obviously been messed with and I can't seem to find a diagram of which wires go where on the transistor, so I have no clue if the rigged up transistor/ballast wiring is even correct. On top of that I have 3 loose wires in the area, 2 black and a brown with no where to go, I have the fsm but hard to know whats what with loose wires floating around. 

 

I'm thinking about just going straight to a pertronix ignitor II/flamethrower II combo with new plugs, wires, cap, rotor etc but need to figure this wiring out first. Can anyone tell if running pertronix deletes the transistor/ballast or are they still used? I'm reading conflicting things about the install.

 

Any help is greatly appreciated. Thanks!

240z1.jpg

240z2.jpg

240z3.jpg

240z4.jpg

Share this post


Link to post
Share on other sites

That definitely looks messed with, because that ignition box is supposed to be in the passenger footwell. Look up the ignition chapter in the FSM and also take a look at the chassis wiring diagram. The ignition isn't very complicated, so you should just be able to match up the wires and get it going.

 

If you can get a 280zx matchbox distributor, those are even more simple to wire up and provide a nice hot spark for cheap.

Share this post


Link to post
Share on other sites

Somebody has already converted to electronic ignition.  That box is an ignition module but it's not clear which car it came from.  Probably better off just springing $25 and converting to a GM HEI module.  The old modules like that one are all dying anyway, plus that one is not supposed to be outside of the cabin.  It's probably corroded inside.  It looks like the wires are all correctly connected, assuming they were in the beginning.  Two from the distributor, the coil wires, and a ground..  So either the module or the distributor pickups are bad.  

 

Your distributor is probably from a 280Z.  Take the cap off and you won't see points.

 

 

Share this post


Link to post
Share on other sites
4 minutes ago, ZHoob2004 said:

That definitely looks messed with, because that ignition box is supposed to be in the passenger footwell.

 

He has a 240Z.  Electronic ignition didn't show up in the Z's until the 260Z.  That's somebody's upgrade.

Share this post


Link to post
Share on other sites
36 minutes ago, NewZed said:

He has a 240Z.  Electronic ignition didn't show up in the Z's until the 260Z.  That's somebody's upgrade.

 

Saw the transistor box and assumed it was just someone's misguided rewiring project. Now that I look I see it's worse (better?) than that. HEI seems like a good direction to go from here, but you could basically do anything because you might as well start over from scratch.

Share this post


Link to post
Share on other sites

No wonder I couldn't make sense out of it or find any diagrams. This is the first 240z I've worked on. I looked at the distributor but assumed it was stock because I thought all 280zx distributors had the module mounted on them. Here's a pic of it if anyone can tell me if it's stock or not.

 

I would like to just revamp/ugrade the entire ignition system with new parts...so what's the best cost effective method from a setup like this? I've read about problems with the reman 280zx distributors and modules...pertronix seemed like it would be easier and straight forward. Opinions?

IMG_20180607_101919.jpg

Share this post


Link to post
Share on other sites

Alright, after looking through some parts this is a 280z distributor and transistor box. I actually have extras of both from my 280 parts car. Now if the car ever ran like this or if it's even possible for it to run like this I don't know. I can't find much info on using 280z distributors..everything is about the 280zx distributor swap. So where to go from here...should I try to get it running with extra parts I have around or just pull everything out and go 280zx or pertronix.

Share this post


Link to post
Share on other sites

It would run like that.  If you have a similar box you could just swap the wires over.  There might be ID marks on the terminals also to help out.

 

Lots of options.  Except that there's no Pertronix for a 280Z distributor, which is what you have there.  The GM HEI module swap is pretty simple and it's more weather resistant.  It would live in the engine bay.

 

Disconnect the red and green wires and measure resistance on the distributor side.  That's a test for the pickup coil.  Check the air gap.  See if the breaker plate bearings are good and the plate rotates for vacuum advance.  It's all shown in a 280Z Engine Electrical chapter.

 

Here's a HEI module swap guide.  It's actually easier to just know that B is switched power, C is coil negative, G is the green wire from the dist., and W is the red one.  And the module needs to be well grounded through the mounting holes.  You don't need that ballast resistor or old 240Z coil either.

 

http://www.sonic.net/~kyle/gmhei.html

 

 

 

Share this post


Link to post
Share on other sites
1 hour ago, NewZed said:

You don't need that ballast resistor or old 240Z coil either.

If you do get rid of the ballast resistor, replace the coil as well. That coil will not survive the full 12v for more than a few hours, and can short and take your wiring with it.

Share this post


Link to post
Share on other sites

Thanks for the help, I did get it to fire with this rigged up setup and a extra transistor I had sitting here....however, I went ahead and ordered a 280zx distributor (guaranteed to have a good module), along with a new coil, resistor, plugs and wires. Ignition should be good to go now....on to the carbs. Thanks guys.

  • Like 1

Share this post


Link to post
Share on other sites
54 minutes ago, damesta said:

280zx distributor (guaranteed to have a good module)

 

Nothing is guaranteed with reman parts but you can return them until you get a good one.  Good luck.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×