Coil Question

[Khurram Darugar]

Hiya
Does anyone know if you take the middle wire (one coming from the coil) off the distributer cap and place it on the engine should the coil spark continuously or just once?  I'm getting one spark.
and nothing out of the 123   Had to get the car towed home.

Upon recommendation from a local garage I'm running a 12V coil with no resister.  Coil is new as is the 123 unit.
Thanks
Kay

[Naj ✝︎]

Yes, Kay,

Once every time you switch it off and then on.

Thats what the distributor does, switch the coil on and then off to produce the spark.

If you're not getting a spark at a plug lead from the 123 while cranking, that could be at fault?

naj

[Khurram Darugar]

Hi Naj,
Thanks I now know what the coil distributor relationship is  
I have been in touch with 123 and they are going to service the unit.  They seem pretty helpful.
Here is a snippet from Frank's response which might be useful to the group.

"Some Mercedes coils have a very low primary resistance.
When the primary resistance of the coil is below 1,0 Ohm the ignition will be damaged."

Once back I'm going to try and time it myself!!    

Kay

[Naj ✝︎]

Upon recommendation from a local garage I'm running a 12V coil with no resister.  Coil is new as is the 123 unit.

"Some Mercedes coils have a very low primary resistance.
When the primary resistance of the coil is below 1,0 Ohm the ignition will be damaged."

So, what coil are you using?

naj

[Khurram Darugar]

Naj I running a brandless ebay job which has a stated resistance of 1.5 to 3.2 ohms.
Im thinking of going to a accuspark coil with resistance at 3ohms flat.  Other option would be to keep the same coil and add a 1 ohm ballast.
I will probably go with the accuspark.
Kay

[450sl]

Kay,

I bought a 123 as well , during the installation the electronics in the unit went down , 123 replaced it as service.  123 ROCKS 

[Khurram Darugar]

I just wanted to update this thread. 
It took a bit of trying but in the end, the spring at the bottom of the 123 Ignition was too long.  It was pushing the distributor out, so it was out of sync.  Basically just chopped it in half and cars pretty stable now.
So in the end i learnt the hard way that spring really is a pain.

 
Kay