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Ahh broke at the office.....no fire from ignition system

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dodgestang

Active Member
Using a meter:

Battery 12.5
Battery at Solenoid 12.5
Start post of solenoid 12.5 when starting
Run post of solenoin - 0 volts when key is on, 12.5 volts when key is off?

Seem wierd so I am heading out to buy a new solenoid.

I have also done spark test - no spark from coil. So I replaced the coil first.
I have done MSD 6a standard test to force the coil to fire...and it failed which means there is no power to the MSD box.
 
Hot wire around the solenoid to provide power to the MSD....if the solenoid still cranks the car over.
 
New coil - issue persists
New Solenoid - issue persists

I don't really have the tools to break into the wiring harness and try to hardwire the MSD box straight to the battery.
 
Not sure what the "standard MSD test" means but if you have a bad box couldn't that also cause the "test" to fail?

I am presuming the starter turns the engine but you're not getting the plugs to fire. Pretty basic system in play here, as you know. I'm thinking your MSD has died.
 
Bad ign. switch?

Can you use a jumper cable to try a temp. hardwire? Otherwise....tow truck....
 
"dodgestang" said:
Using a meter:

Battery 12.5
Battery at Solenoid 12.5
Start post of solenoid 12.5 when starting
Run post of solenoin - 0 volts when key is on, 12.5 volts when key is off?

Seem wierd so I am heading out to buy a new solenoid.

I have also done spark test - no spark from coil. So I replaced the coil first.
I have done MSD 6a standard test to force the coil to fire...and it failed which means there is no power to the MSD box.
Click to expand...

Was this with the coil run wire attached to the solenoid or with the solenoid bare of wires except for the battery cable? I'd run the test with the latter condition. Your MSD box may be dragging the voltage at the run side of the solenoid down to ground.
 
Run the tests with everything hooked up but the run wire (should be brown) at the solenoid. Measure the voltage at the solenoid post where this wire would go and also at the wire end. Make sure the key is in RUN. The starter solenoid should be zero itself and the wire should be 9-12 V. Next, put the key in CRANK and the solenoid post should go to 12V.
 
Does this car have an in dash tach? What about in start position does it get 12v? I had a similar issue and my tach went bad and that killed my ignition.
 
No it is an aftermarket column mounted tach....that didn't work when I got the car. It is wired to the tach port on the box and appeared to have 12v when I looked it previously....but haven't paid much attention
 
"opentrackerSteve" said:
Put the points dizzy back in. Betcha it runs.
Click to expand...

I'm sure. Only prob is this is a new to me car.

I have a 65 with a 351c and full msd setup (box and dizzy)
I have a 67 with a 302 and points
I have this 68 with a full MSD setup (box and dizzy)

So not a lot of swapping going on ;)

Since it is home now this weekend if I get time I'm going to trace wires and look for electrical gremlins. I will most likely start by simply unwiring the box and hard wiring it direct to 12v source. This will eliminate all the old wires and take one more variable out of the equation.
 
If it had quick disconnects you could swap the box from the 65 into the 68. Probably not that easy though. Definitely check for full power input for the box.
 
Nick,
Does the MSD box have a small white wire? If so, is it being used or is it accidently grounded which becomes a kill switch?
 
"cmayna" said:
Nick,
Does the MSD box have a small white wire? If so, is it being used or is it accidently grounded which becomes a kill switch?
Click to expand...

White wire is not in use but it was all taped up inside the harness with no 'apparent' shorts to ground.
 
I had this same issue and it was simply a bad crimp on a butt connector. Unfortunately I had my foot into the 460 pretty good at the time when the wire decided to part ways with the butt connector and the resultant mechanical whip lash sheared the pin on the dizzy gear. Took me two days to figure it all out (yeah, I'm not to bright). My point is because it is a new to you car don't overlook the simple stuff like a loose wire.
 
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