I was messing with the 73 we have and trying to get it running again with my son. The brake booster was out and disassembled we patched it and reassembled it. Tried to start the car but no spark. I believe I have fuel and I shot some ether to it so I don't think fueling is the main issue right now.

 

Tried to ground a plug on the valve cover, no spark

 

Tried to ground the coil lead, no spark

 

Checked voltage at the coil, I have voltage at the coil but am not sure what I want exactly

12v on both sides of the coil I believe, 12v on one side of the ballast, lower on the other side

 

Check continuity to ground from the spade on the outside of the dizzy, good

 

Continuity back into the dizzy from the spade to the points, good

 

Tried a coil from a different car, no joy

 

The car did run but probably not for a year or so.

One other thing was when my son set the battery in I set the terminals on it backwards because he had the battery turned wrong.

 

Can y'all give me some systematic method to check the ignition system? I don't totally understand how the system is setup.

Thanks

Points?  You should be able to turn the engine or distributor to where the points are closed (said open before), then open and close them by hand to see if the coil discharges.  You can also measure coil voltage and ground at the points.  They have to open completely and close for the spark to be produced.

 

Sorry, may not be the best system.  I like to follow the paths and see what's not happening that's supposed to.

Edited April 26, 20159 yr by Zed Head

Ok I will try manually triggering the points

Thanks

Didn't they start with transitorized ignition in 73? I thought I used to have an old brain box from a 73

Could have been a 73 build 74 260Z.  260Z was the introduction of the transistorized ignition in the states.  As I understand things.

I was having trouble totally understanding the operation of the points system. I found this video that boiled it down nicely. Lots of pictures always makes it better. Like I tell my wife 80% of all male communication is non-verbal

https://www.youtube.com/watch?v=W94iksaQwUo

Another for electronic ignition

 

https://www.youtube.com/watch?v=QYx8J_5l5wY

Steve,

I believe the points setup is stock but I don't know for sure. This car is not pristine, so who knows...I don't see a lot of loose connections like I would expect if an electronic ignition had been removed.

My 1973 240Z had points (from factory).

Patcon:  You might check the fuseable link down by the starter.  You said the battery was hooked up backward, that could of melted part of the link.  The very same thing happened to me during my refurbishment, hooked them up backward, looked down and saw the fuseable link smoking and quickly removed it from the post.  The link was melted about 3/4 of the way, found a replacement.  The car had original black battery cables.  Easy to cross.  Not any more.     My very late 73 came with and still has the points system, and original wheel covers. 

 

Bonzi Lon

Charles, let me know if you continue to have issues. I might be able to do a house call.

Checked voltage at the coil, I have voltage at the coil but am not sure what I want exactly

12v on both sides of the coil I believe, 12v on one side of the ballast, lower on the other side

 

Your measurements don't really make sense... I've attached a snipped from the FSM with some of my notes to help. The measurements you should see depend on if the points are open or closed.

 

 

If the points are open you should have +12 volts on pretty much everything:

a) +12 on both sides of the ballast

2) +12 on both sides of the tach

c) +12 on both sides of the coil

 

If the points are closed, the readings are a little different. With the points closed, you should have:

a) +12 on the ignition side of the ballast

2) Something a little less than +12 on both sides of the tach and the coil positive

c) Ground on the coil negative

 

And I like the spurious "y'all" thrown in there for good measure!   ::  Just trying to get my attention?