texas67coupe

hey guys,

Well short story then my question? I have an msd 6al, msd coil, and had petronix 1. Well the other day I was starting car and it stalled while I was inside. So I got stuck with the key being left in the on position and the car would not restart at all. I figured from research that I fried the pertronix. So I went ahead and installed a pertronix 3 to replace the 1. It is operating (red LED comes on with 12.5 or so volts. Nothing has changed, but I am still getting no spark.

I disconnected coil wire at distributor, touch it to ground with car in run and no spark. What else could this be?? The coil and MSD are only 2 months old. Thanks for any help.

kalli

I'd bet you fried the coil. The pertronix I don't have a left the key in ignition position which overhears coils. Pertronix 3 has it. The pertronix 2 as well. You can check the coil with an ohm meter. There should be articles on the Internet. But and here's the big but. If you run a msd 6 al there should be no wire at the coil apart from the ones coming of the msd box. I think it's orange and black. Absolutely nothing else apart from that and the middle one going to distributor. Can you confirm that?

texas67coupe

Thanks for reply. Yes the orange and black are the only wires attached to the coil. Everything was working fine until the key being in the on position after it stalled. I don't know how long it was that way but maybe 5 to 10 minutes.

texas67coupe

so I bench tested the coil and got a 1.1 on the primary and no reading at all on the secondary test. MSD says .7 on primary and 4.7 on secondary.
If it was fried would I get no reading at all on the secondary. I'm guessing this may be my problem. I will get a new coil tom and check it out after work. Any input on the coil test would be great.

texas67coupe

so I have no patience and picked up a new coil. it did not fix the problem. I still have no spark. With the new coil in, I conducted the white wire test on the msd box. With the white wire grounded using light bulb tester to ensure it was, there was no spark from the coil wire. So now i'm thinking it may be the msd 6al box. It is getting the same 12V as the pertronix 3 which is working via the red led light and volt test. Is it possible the msd box is bad???? not sure how else to test it. MSD website only has the wire test or send it in. What a pain in the a##. Any advice would be great, all was working fine till my key on deal.

mikenkiki05

i would say the msd box is fried from years of dirt track racing the msd's have a resistor in them that burns out if there is a constant power to it with not firing, its real complicated but if i was a betn man id bet the msd is out, all the msd's ive saw are sealed from the factory and if seal is broken they wont even look at it

texas67coupe

Well , I just went ahead and unhooked the msd 6 al and connected the pertronix 3 directly to my coil and switched ignition wire and it started right up. So, I just ripped out the 6 al and have a few wires everywhere that had to be tucked away from my tach and msd tach adapter. What a pain, so after a few zip ties and adjusting the timing and vacuum it's running like a champ. So I guess I'll send the 6al in to get looked at. Not sure if it's worth it, I might just go pick up another one. What you guys think.
Thanks for all the help.

mikenkiki05

unless your running it for drag no need for a msd box jmho, they make the 40,000 + volt coils i think accel makes one and i know msd does, but not sure if it will run without the msd box, msd's are nice since u can chip thew different which is nice but in all the years of racing dirt track and been round racing for 32 years msd's are way over rated, a stock hei dist, with a few tweaks can out proform a msd any day of the week, unless its used for traction control lol, also was your msd bos mounted vert or horz? that makes that tiny lil resistor work 100 times harder if mounted vertical,

kalli

well ya, if it's the MSD box you can run the car without it in the meantime if you are in a hurry. Did you measure the new coil as well to compare with the old one? infinite resistance on secondary would suggest a burned secondary coiling.

there's a test you can do on the MSD boxes. it's basically grounding a specific cable (tapping it against ground). whenever you do that you should get a spark.
Check the manual for it, i'm not sure how exactly you have it wired. if unsure I can have a look later on. Another thing is that if you hold the spark plug wire directly to ground you will see no spark, you have to hold it away from ground (a small gap so a spark can jump across).

try that, this will tell you if everything with coil, spark plug wire and MSD box is ok

Kalli

texas67coupe

The msd box was mounted vertically on the driver shock tower. So now it's out completely and I'm running the pertronix 3 and a blaster 2 coil. It fires up on fist try and throttle response is as good as it was with msd. I adjusted the timing a little and used vacuum gauge to adjust carb. So now I'm gonna mail the box in to msd as all the tech checks I performed failed so it is definitely the box. Now the debate will be just leave it out or put it back in when it gets back. I just don't want to have issues again in the future with this. I also don't want to rewire the tach right now as it was hooked to the msd through a tach adapter. I'm guessing I can just hook it straight to coil now if I leave box off.

What you think is best. I had the box on for improved spark etc but if I really don't need it unless for racing should I just leave it off?