123 distributor no spark

[47silver]

Installed a 123 distributor in a 75 911.
Wired into an msd.
Red to switched power, blue ground and black to the msd trigger.
Turned the distributor with power and ground only and watched the green light. All good so far.
Communicated with blue tooth added a curve but there is zero spark. Tried numerous things but still no spark.
Reinstalled my old distributor and engine fired.
Was it immobilized does that need turned off?
Or is it the blue coil?

[Schulisco]

Which 123 model is it? Tune? USB? Bluetooth?
If its a Tune I firstly would program a 0° curve to see if it starts and to confirm that engines fires at 0° too. Do you use the correct input on the MSD box? Which MSD box do you use?If the 123 is the early one for your car it's a breaker point version which also required breaker points input of the MSD box. The BT version got an immobilizer. Which dizzy is the original one? Do you used the MSD too with the old dizzy?

Thomas

[47silver]

Blue tooth 123 new.
Msd 6al
Original distributor 04

123 has 3 wires. The black wire goes to the trigger wire of the msd. Which is white.

The msd worked with points and with a pertronix.

Will try 0 degrees

[Schulisco]

Originally Posted by 47silver

Blue tooth 123 new.
Msd 6al
Original distributor 04

123 has 3 wires. The black wire goes to the trigger wire of the msd. Which is white.

The msd worked with points and with a pertronix.

Will try 0 degrees

Seems to be correct. Afaik the MSD 6AL has both a red and a white wire handling the trigger output. Probably you have to connect that red wire to +12V / ignition as well. White remains the trigger. That trigger signal is basically switching the white wire to ground which is the coil trigger in case of operating the 123 without an MSD box.

No matter which ignition curve is programmed the 123 must produce a trigger signal.

If all tests fail take the 123 out of the car and make a test stand outside of it to prove it's working. Keep aware of high and potential deadly voltages!

Thomas

[47silver]

the msd is powered properly. It works with the old distributor.
the red wire from the 123 goes to the keyed powered.
the black wire goes to the trigger to the msd
blue wire to a ground.
Cannot see any wiring mistakes.
i will re-install and bypass the msd and wire it directly to the coil as shown on the 123 site

[icarp]

Where did you buy your 123 dist?
The seller should be able to help you with spark and curves
Ian

[mysocal911]

Originally Posted by 47silver

Installed a 123 distributor in a 75 911.
Wired into an msd.
Red to switched power, blue ground and black to the msd trigger.
Turned the distributor with power and ground only and watched the green light. All good so far.
Communicated with blue tooth added a curve but there is zero spark. Tried numerous things but still no spark.
Reinstalled my old distributor and engine fired.
Was it immobilized does that need turned off?
Or is it the blue coil?

Why are you also using a MSD? You are aware that the 123 dist can directly drive an inductive discharge coil?
Although, this setup may require a tach signal mod, it's simple.

Furthermore, the 123 dist will provide a much better spark than the MSD, like what the 911 3.2 and all later Porsches use, i.e. an inductive discharge spark.

[mysocal911]

It doesn't get any simpler than this:

[Schulisco]

Originally Posted by mysocal911

Why are you also using a MSD? You are aware that the 123 dist can directly drive an inductive discharge coil?
Although, this setup may require a tach signal mod, it's simple.

Furthermore, the 123 dist will provide a much better spark than the MSD, like what the 911 3.2 and all later Porsches use, i.e. an inductive discharge spark.

Dave,

just a technical addendum to this from my side.
CIS and earlier carbs run general richer mixtures. They may worsier to ignite. Later Carreras run generally leaner therefore they require less igniting energy.
Bosch CDI single shot: 122mJ, on 8000rpm 47mJ (mJ=milli Joule) Source: www.911-hkz.de
MSD advertises with 135-145mJ per spark on the MSD 6AL.

In general spark energies vary between 40-60mJ to ignite securely. That's one of the reasons Porsche stayed on the 930's with the Bosch CDI. On stochiometric mixture you only need 0.2mJ, leaner or richer mixtures at least require 3mJ to ignite them securely according to my "Automotive handbook" from Bosch.
Unfortunately I have no exact numbers about the spark energy from the Bosch Motronic/L-Jetronic of the 3.2 Carreras, but I suppose they are noticeable higher than the 3mJ but not that high as the CDI / MSD may produce.

But you're right - basically the CIS 911 will also run with the 123 and coil only, without the MSD / CDI box too. But then you have totake care on the tach signal too. I run the Permatune box together with the 123 with success and no issues.

Kindly reminder: https://forums.pelicanparts.com/porsche-911-technical-forum/1151696-ignition-question-71t-s.html

Thomas

[PeteKz]

I agree with Dave about setting up the 123 directly to the coil and bypass the MSD. Get it running that way first and dial in the timing. Then add the MSD. That sounds like your plan too.

Please post your results back here.

[snbush67]

Did you check the app immobilization? It should be off as shown in the below picture.

[mysocal911]

Originally Posted by Schulisco

Dave,

[B]just a technical addendum to this from my side.
CIS and earlier carbs run general richer mixtures. They may worsier to ignite. Later Carreras run generally leaner therefore they require less igniting energy.
Bosch CDI single shot: 122mJ, on 8000rpm 47mJ (mJ=milli Joule) Source: www.911-hkz.de
MSD advertises with 135-145mJ per spark on the MSD 6AL.

A common misconception, the IDI (inductive discharge ignition) produces as much spark energy with the added benefit of longer burn time approaching 1ms, where the typical CDI barely reaches .50 ms. And as noted before on the Forum, the multi-spark system (short spark pulses) has marginal benefit.

Originally Posted by Schulisco

In general spark energies vary between 40-60mJ to ignite securely. That's one of the reasons Porsche stayed on the 930's with the Bosch CDI. On stochiometric mixture you only need 0.2mJ, leaner or richer mixtures at least require 3mJ to ignite them securely according to my "Automotive handbook" from Bosch.
Unfortunately I have no exact numbers about the spark energy from the Bosch Motronic/L-Jetronic of the 3.2 Carreras, but I suppose they are noticeable higher than the 3mJ but not that high as the CDI / MSD may produce.

But you're right - basically the CIS 911 will also run with the 123 and coil only, without the MSD / CDI box too. But then you have totake care on the tach signal too. I run the Permatune box together with the 123 with success and no issues.

Kindly reminder: https://forums.pelicanparts.com/porsche-911-technical-forum/1151696-ignition-question-71t-s.html

Thomas

Given the limited production of the late '80s Turbos, Porsche decided not to switch to IDI. And don't forget the Porsche 965 (964 Turbo) which used an IDI system.

[pmax]

Originally Posted by mysocal911

It doesn't get any simpler than this:

As a rule, the simpler the better.

[47silver]

Since I could not get any spark and reinstalled the old distributor and it started.
I called the supplier Ed in Ohio, and he immediately called me back.
he suggested that:
Install the distributor and set it up as described with the green light.
Where the rotor is located the next spark plug will be number 1.
Put all of the curves to 0 degrees at all rpms.
If it does not start, have someone try starting the car and manually turn the distributor body to advance the spark and it should start.
Now synchronize the app to the distributor and motor with a timing light.
adjust the distributor to be at 0 degrees.
that will coordinate the APP to the distributor and motor.
Then tighten everthing down and setup the curve as you want.

I have not had time to do this but I think it will work and will post what I did to install it.

[Schulisco]

Sounds reasonable strategy, similar as I also suggested in #2. Nevertheless I would first wire the 123 in the car without stuffed into the engine. Then take a spare spark plug and connect it with a spark wire, switch ignition on and turn it by hand to see if it produces sparks...make sure that the 123 and the spark plug also gets additional engine ground by extra wire to the 123 housing.

Thomas