Msd run-on!Has anybody experienced this?

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pettybludart

pettybludart

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I have installed a MSD 6AL box and ss coil in my 66 Dart with factory mopar elec. dist.I have the car running,but when I go to turn it off with the key,it stays running?In the instructions,they call this run-on.It says to put a jumper wire on the dual ballist on one side and little red wire on the top and run a ground to the bottom on the other side.Has anyone tried this with good results?Thanks,any help would be great!

P.S 360 LA engine
 
1wild&crazyguy said:
So all msd 6a, blaster 2 right?

And you have the ignition feed coming from the ballast in? skipping the ballast all together too right?
Click to expand...
Yes running the box straight to batt. and ground,also used the wire supplied(green and purple)to hookup distributor.I ran little red wire to pass. side of ballist.Is this wrong?
 
Sounds like the way I've always wired them and not had any problems. Did the car shut off before you installed the MSD box?
 
fishy68 said:
Sounds like the way I've always wired them and not had any problems. Did the car shut off before you installed the MSD box?
Click to expand...
Yes it shut off.I,ve replaced the harness from the block also,with a good one froma 66 Cuda.The last one was spliced and cut and burnt at the block when I got the car,so I,ve replaced it and took out the ecu to add the MSD 6AL box.Fishy68.did you do the bypass?
 
So if I run the small red wire with 12V switch to one side of ballist on top,ground on bottom and a jumper wire on the other side,it should turn off with the key?
 
Is that a 4 wire ballast? If so I haven't wired one of them. Only 2 wire ballasts. I'm not sure what the other 2 wires on a 4 wire ballast are for. sorry.
 
4 prong is what I have.
I pulled the bottom right hand ignition wire off and plugged it to the box, if I remember right.

btw 4 post=5 pin
They jump from the bottom 2 posts and are for low volt wire on 5 pin setups.
 
I run the switched power to the starter relay and to a toggle.You have to kill the motor with the toggle this way.I try and keep it independently wired on its
own so its not running through the cars whole electrical system.Works as a
anti theft detterent too since the switch has to be on to start the vehicle.JFYI.
 
1wild&crazyguy said:
4 prong is what I have.
I pulled the bottom right hand ignition wire off and plugged it to the box, if I remember right.

btw 4 post=5 pin
They jump from the bottom 2 posts and are for low volt wire on 5 pin setups.
Click to expand...


Mistake, I actually pull the jumper lead to the upper low voltage wire, for the 5th pin, and hook the box to it and just pull and tape the other low volt wire.

So I use it now like a 2 post.

Here's a pic if it helps.

Photo 465.jpg
 
No reason to keep the ballast resistor in the circuit with an MSD, it's just another point of failure and provides no purpose. Just jumper the connector on the side of the 4 pin ballast that used to go to the coil. No need to touch the other side at all. Then attach the blue wire that used to go to the coil + to the small red wire on the MSD.

The on/off signal to the MSD does not require much voltage and is the reason it normally works with the ballast still in the circuit. After re-wiring per above if you still get run on then you have a short some where in your electrical system that is keeping enough power to the ballast circuit to maintain the MSD in the on condition. Putting in a toggle switch will work put the short is still there and will likely manifest it self in other ways at the most inopportune time. I recommend you take the time to trouble shoot the short and fix it.
 
Well I threw in a heavy duty toggle switch to kill all power,I,ll search for the problem and rewire when I get more time.Thanks again for all help and suggestions.
 
dgc333 said:
No reason to keep the ballast resistor in the circuit with an MSD, it's just another point of failure and provides no purpose. Just jumper the connector on the side of the 4 pin ballast that used to go to the coil. No need to touch the other side at all. Then attach the blue wire that used to go to the coil + to the small red wire on the MSD.

The on/off signal to the MSD does not require much voltage and is the reason it normally works with the ballast still in the circuit. After re-wiring per above if you still get run on then you have a short some where in your electrical system that is keeping enough power to the ballast circuit to maintain the MSD in the on condition. Putting in a toggle switch will work put the short is still there and will likely manifest it self in other ways at the most inopportune time. I recommend you take the time to trouble shoot the short and fix it.
Click to expand...

coils kill ballast resistors. fyi
I haven't lost a ballast since.
 
1wild&crazyguy said:
coils kill ballast resistors. fyi
I haven't lost a ballast since.
Click to expand...

But with an MSD the ballast does not connect to the coil at all. The circuit with the ballast resistor is only used to turn the MSD on and off. Power to run the MSD is direct wired. No need to keep it in.

FWIW, in an inductive ignition system the purpose of the ballast is to protect the coil from over heating and failing.
 
Well I figured out that I needed the modern voltage regulator,which I pulled out with the ecu when I installed the MSD.I wired it back in and the car is finally chargeing and turning off.Thanks for all the trouble shooting help guys,couldn,t have done it without some experienced help.Now to go burn some skins up!

car pics 66 Dart 004.jpg
 
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