Electronic Ignition -Datsun 260z 2+2

[hamid]

Hi
I wonder if anyone else had the same issue : I have a 260z 2+2 currently at Fourways engineering and we have a issue with the rev counter, they have tried putting , another set of electronic ignition, another electronic distributor, 3 rev counters, had their auto electrician in to look at the wiring, and it works perfectly with points and is still intermittent with electronic ignition.
As a result of this it looks as if they need to put it back to points instead of electronic ignition, does anyone has any suggestions ?

 

[jonbills]

Its certainly common for people to have problems with the revcounter when swapping to electronic ignition. Normally its because they've left the revcounter wires disconnected by the coil. But I wouldn't expect Fourways to get it wrong.
Does it work on points? Its possible that the wiring to the revcounter from the engine bay is faulty.

 

[Farmer42]

There are some ignition wires that need joining together to get the Tacho to work with electronic ignition. Have a look at this webpage which gives a diagram if you are using a E12-80 ZX dizzy. It also works for 123 ignition dizzys.

https://www.atlanticz.ca/zclub/techtips/distributor/

As already said, I would have expected Fourways to know this

 

[Fairlineguy]

Hi
I wonder if anyone else had the same issue : I have a 260z 2+2 currently at Fourways engineering and we have a issue with the rev counter, they have tried putting , another set of electronic ignition, another electronic distributor, 3 rev counters, had their auto electrician in to look at the wiring, and it works perfectly with points and is still intermittent with electronic ignition.
As a result of this it looks as if they need to put it back to points instead of electronic ignition, does anyone has any suggestions ?

What type of Rev counter do you have ? 260z can be fitted with either the inductive loop rev counter or the later with a signal
wire direct to the coil
Depending on which you have will effect how it’s wired. I assume you have deleted the ballast resistor

 

[status]

Put 280 zx ignition on it if I remember rightly take the ballast resister off and join those wires together

 

[hamid]

Its certainly common for people to have problems with the revcounter when swapping to electronic ignition. Normally its because they've left the revcounter wires disconnected by the coil. But I wouldn't expect Fourways to get it wrong.
Does it work on points? Its possible that the wiring to the revcounter from the engine bay is faulty.

Its certainly common for people to have problems with the revcounter when swapping to electronic ignition. Normally its because they've left the revcounter wires disconnected by the coil. But I wouldn't expect Fourways to get it wrong.
Does it work on points? Its possible that the wiring to the revcounter from the engine bay is faulty.

Hi , Yes it works with points, they said they have changed the wires, and also changed the rev counter with another one and still the same issue

 

[hamid]

There are some ignition wires that need joining together to get the Tacho to work with electronic ignition. Have a look at this webpage which gives a diagram if you are using a E12-80 ZX dizzy. It also works for 123 ignition dizzys.

https://www.atlanticz.ca/zclub/techtips/distributor/

As already said, I would have expected Fourways to know this

Thanks, I will let them know in any case.

 

[hamid]

Put 280 zx ignition on it if I remember rightly take the ballast resister off and join those wires together

Done that and still the same.

 

[status]

Get an auto electrician that knows his stuff,yes hard to find now days

 

[toopy]

This may be of use

 

[Farmer42]

This may be of use
View attachment 59718

That's the diagram I posted earlier in the thread.

 

[toopy]

That's the diagram I posted earlier in the thread.

Yep, sorry just checked the link, i didn't scroll all the way down!

 

[AliK]

This is not rocket science! So it should be easy to track down and resolve. When you say intermittent, what does that mean? Does it mean the engine doesn't run right? Or the rev counter is intermittent? Or both?

Let's make zero assumptions about what Fourways did or didn't do, let's just ask some questions:

1. On my 2 seater '77 260z I had to add the additional wire going to the B of the IC ignition box for the 280zx ignition to work properly. Have they added that? I can't imagine it firing without it, so I'm thinking yes will be your answer.

2. What coil are you using? Does it need to be Ballasted? If not, has the Ballast resistor been bypassed by connecting it's connectors together? FYI mine worked just fine with a ballasted and unballasted coil.

3. Have they tried connecting the GW wire in the diagram above directly to the battery (via a standalone fuse) to bypass potentially dodgy car wiring from the ignition switch etc?

4. What tach is in your car? On my 260z the tach loop looks like the photo below - do you have the same looking loop like the pic posted by @Fairlineguy above? Note how on mine there are 2 loops on the pickup (i.e. 3 passes over the pickup) - does yours have that? The more passes, the stronger the pickup signal.



5. Did they replace the coil too? I'm wondering if the signal coming from an old coil (potentially combined with fewer pick up loops) may be causing an issue.

The diagram below shows the waveform of what is happening on the coil +ve and what the rev counter sees. The red area is what drives the rev counter so you need a strong enough pulse to a) come through, b) be picked up by the pick up being looped hence adding extra loops can help.


5a. Did the auto-electrician use an oscilloscope to look at the coil waveform and compare with a healthy trace? (I wager not, but let's make no assumptions)

6. Finally, have they tried a 123 Ignition distributor with the same result?

IMHO you're not getting a strong enough pulse hitting the tach.

 

[hamid]

This may be of use
View attachment 59718

Thank you , will definitely give it a try.

 

[hamid]

Its certainly common for people to have problems with the revcounter when swapping to electronic ignition. Normally its because they've left the revcounter wires disconnected by the coil. But I wouldn't expect Fourways to get it wrong.
Does it work on points? Its possible that the wiring to the revcounter from the engine bay is faulty.

Thank you

 

[hamid]

This is not rocket science! So it should be easy to track down and resolve. When you say intermittent, what does that mean? Does it mean the engine doesn't run right? Or the rev counter is intermittent? Or both?

Let's make zero assumptions about what Fourways did or didn't do, let's just ask some questions:

1. On my 2 seater '77 260z I had to add the additional wire going to the B of the IC ignition box for the 280zx ignition to work properly. Have they added that? I can't imagine it firing without it, so I'm thinking yes will be your answer.

2. What coil are you using? Does it need to be Ballasted? If not, has the Ballast resistor been bypassed by connecting it's connectors together? FYI mine worked just fine with a ballasted and unballasted coil.

3. Have they tried connecting the GW wire in the diagram above directly to the battery (via a standalone fuse) to bypass potentially dodgy car wiring from the ignition switch etc?

4. What tach is in your car? On my 260z the tach loop looks like the photo below - do you have the same looking loop like the pic posted by @Fairlineguy above? Note how on mine there are 2 loops on the pickup (i.e. 3 passes over the pickup) - does yours have that? The more passes, the stronger the pickup signal.

View attachment 59726

5. Did they replace the coil too? I'm wondering if the signal coming from an old coil (potentially combined with fewer pick up loops) may be causing an issue.

The diagram below shows the waveform of what is happening on the coil +ve and what the rev counter sees. The red area is what drives the rev counter so you need a strong enough pulse to a) come through, b) be picked up by the pick up being looped hence adding extra loops can help.
View attachment 59727

5a. Did the auto-electrician use an oscilloscope to look at the coil waveform and compare with a healthy trace? (I wager not, but let's make no assumptions)

6. Finally, have they tried a 123 Ignition distributor with the same result?

IMHO you're not getting a strong enough pulse hitting the tach.

 

[hamid]

Thanks for getting back to me on this , everyone has been really helpful with this, many thanks.