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moneysmarts
Thought I'd get geared up for the spring
New plugs, rotor, cap, wires, and Bosch Blue coil.
All installed, nice and neat, fired up the engine, ran fine for 60 seconds....then dead.
No spark at all. Put all the old stuff back, still no spark.
Is my new coil not compatible? It's the same part number as the one I've been running for 10 years. Did I smoke the MSD 6AL?
Please advise
Retroracer
Some thoughts on things to check:

1) the MSD 6AL has a LED which can aid in diagnostics; pull up the instruction PDF and see the options listed; this has helped me in the past

2) I've read that the MSD boxes are unhappy with solid core plug wires; were your fresh new wires solid core? Unclear on the failure mechanism that results, whether coil or MSD box would suffer (or both)

3) check basic +12V battery and switched connections with a DVM or tester to make sure no connections were corrupted (and a solid GND connection from the MSD box too)

hope this helps.....

- Tony

moneysmarts
Thanks Tony
I used the MSD instructions to short the purple and green wires from the box.
It is producing a spark from the coil wire to ground.
Not sure if that means the box is still functioning.
My new plug wires were silicone metallic core, but I swapped then back to the bosch solid copper one's that have been on the car for 5 years.
Still no action.
IronHillRestorations
What engine engine and distributor, and why did you use the green and purple?

The green and purple wires are for a magnetic pickup distributor. Pertronix is not considered a true magnetic pickup.
wndsrfr
QUOTE(moneysmarts @ Mar 8 2020, 06:36 PM) *

Thought I'd get geared up for the spring
New plugs, rotor, cap, wires, and Bosch Blue coil.
All installed, nice and neat, fired up the engine, ran fine for 60 seconds....then dead.
No spark at all. Put all the old stuff back, still no spark.
Is my new coil not compatible? It's the same part number as the one I've been running for 10 years. Did I smoke the MSD 6AL?
Please advise

If you're still using points in the dizzy look closely at them... I've seen a case where the phenolic rub strip that rides on the shaft was worn down to where the points could not open at all....
moneysmarts
It's a bosch 009
'74 2.0
The points are still in there, but set to a wide gap.
Been running this setup like a champ for years.
moneysmarts
Also new plugs gapped at .7mm
Same as previous set up
Gatornapper
There are 3 or 4 different 009 dizzy's.........very different too........

QUOTE(moneysmarts @ Mar 9 2020, 07:25 AM) *

It's a bosch 009
'74 2.0
The points are still in there, but set to a wide gap.
Been running this setup like a champ for years.

moneysmarts
I can look at the part number stamp and clarify.
But it's the same distributor I've had in the car since 1993.
That hasn't changed.
What I renewed was the coil, plugs, plug wires, cap, and rotor.
As far as I can tell, all identical to the old parts.

wndsrfr
QUOTE(moneysmarts @ Mar 9 2020, 05:25 AM) *

It's a bosch 009
'74 2.0
The points are still in there, but set to a wide gap.
Been running this setup like a champ for years.

Are they closing properly? Use a test light or VOM to see that the points are closing and opening...
moneysmarts
QUOTE(wndsrfr @ Mar 9 2020, 06:33 AM) *

QUOTE(moneysmarts @ Mar 9 2020, 05:25 AM) *

It's a bosch 009
'74 2.0
The points are still in there, but set to a wide gap.
Been running this setup like a champ for years.

Are they closing properly? Use a test light or VOM to see that the points are closing and opening...


I'm on it late today.
Thank you
IronHillRestorations
The green and purple wires are for a magnetic pickup distributor, and your 009 is not. Pertronix isn't a true magnetic pickup, so it uses the white wire just like a points distributor.

edit: I've never read anything about shorting the mag pickup wires, and I've done several engine harnesses that have used the white wire. My guess is that fried your MSD box
stownsen914
Maybe try tracing spark through the system. Sounds like you get one from the MSD. Can you try triggering it from the distributor and see if you get spark from the coil? Make sure the points are clean, that's easy to check. Coils fail, do you have a spare to try?
moneysmarts
QUOTE(stownsen914 @ Mar 9 2020, 07:59 AM) *

Maybe try tracing spark through the system. Sounds like you get one from the MSD. Can you try triggering it from the distributor and see if you get spark from the coil? Make sure the points are clean, that's easy to check. Coils fail, do you have a spare to try?


Well, I used a jumper to ground the magnetic pick-up wire hanging unused from the MSD box, but evidently that's not the correct procedure to check the MSD for functionality.
I try to figure out another way to diagnose that.
I swapped my old coil back in, without success.
I have no idea how to get a spark from the coil, as you suggest. I did roll the car so the lobe on the distributor shaft was at the max point and I have good points gap there.

Root_Werks
You mentioned you installed the MSD. If this means you were running regular points/condenser setup, you'll need to remove the condenser for the MSD.
moneysmarts
QUOTE(Root_Werks @ Mar 9 2020, 08:58 AM) *

You mentioned you installed the MSD. If this means you were running regular points/condenser setup, you'll need to remove the condenser for the MSD.

I didn't install the MSD
It came on the car in 2004 when I purchased it.
Has run perfectly with that setup for past 15 years.
(interestingly, the condenser has always been installed)
stownsen914
Sounds like you've done the right things to troubleshoot so far by putting back all the old parts that worked. I'd troubleshoot one step at a time to find the weak link. I.e. measure voltage being output from the MSD, then verify spark from the coil, etc.

In case the MSD is suspect, try wiring up the ignition the old fashioned way with just the coil and see if you get spark that way.
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