How to test an MSD system?

adam911 · 08-02-2010, 05:24 AM

I've just put a 71 engine in my 69 model 911. The car has an MSD system fitted (MSD 6200) and I have a tach adaptor. I've connected the system up, as per my photographs and a copy of the MSD wiring diagram I have. Before I put the carbs on I want to test the MSD system is wired correctly and working. I connected up the unit , turned on the igniton and tested for a spark at the points, but don't have one. I am also not getting any power at the coil. I rechecked the connections and they appear to be correct.

Should I be able to get a spark at the points, as per a regular system?

Is there any way to test if it's wired in correctly?

Thanks in advance

ADam

fastfredracing · 08-02-2010, 05:30 AM

I cannot exactly remember, but there is a test , I think you touch the two trigger wires together and pull them apart, and that should produce a spark, It is all clearly listed in the msd manual, and I believe you can find it on MSD's web site as well

adam911 · 08-02-2010, 06:37 AM

great thanks...I'll have a look and see if I can find a manual online.

Adam

James Brown · James Brown's Garage

The wiring diagram is printed on the rear if every MSD unit or is on line. or ground out the trigger wires and the unit should spark. You won't see any voltage at the coil untill the unit sends 300-400 volts to the coil. BE CARFULL and don't get shocked!!

Brando · Brando's Garage

Ground the "Trigger" wire. This is the one that goes to your points. When it grounds the unit will trigger the coil. If your unit has a "test LED" it will also blink. Make sure the rotor is pointed to a cylinder that you have the plug grounded.

Use insulated pliers or wear incredibly well insulated gloves. You DO NOT want 52,000 Volts going through you. Happened to a friend of mine and his hair nearly ended up permanently in an afro.

Are you still using points and a condenser? With an MSD box you can use the points sans condenser so long as you are not running 12v from the ignition through it. If you are using a compufire/pertronix ignition these do not work with most MSD systems.

adam911 · 08-02-2010, 11:40 AM

Thanks for the reply.

I am using points and a condensor.

Just to be clear, I have to have the distributor cap fitted and a sparkplug connected to the lead that the rotor is pointed at and I have to ground the sparkplug?
Where am I going to see a spark? At the sparkplug or between the trigger wire and ground?

thanks

Adam

James Brown · James Brown's Garage

that's the easy method, you can use the coil wire connected to a plug wire and a plug that is touching the engine metal somewhere. Then fire at will. Might want to switch to a magnetic pick-up system to get rid of the points.

47silver · 47silver's Garage

the 6al msd will work with a pertronix. feed the pertronix from the small red "key on" wire that goes to the msd and the black wire on the pertronix to the porsche tach wire and to the msd trigger wire. have had it in for a few years.