Good info... I have an MSD distributor and 6AL ignition module on our 73 Mach 1, installed by the prior owner. It has been a marvelous system (it came with a 6A module, I upgraded to 6AL for the Rev Limiter, just because I felt it was a good idea). Everything went swimmingly for 5 years. In Father's Day, 2023, I brought our 4 Mustangs and Shelbys to a local car show (the 73 Mach 1 won the Best In Show trophy), and ran well all the way to the show and back home. Once we got home we had 4 cars to jockey around and park them in their various garage stalls. I went to the Mach 1 and found the engine would crank over, and fire up, but as soon s the key was moved to the Run position. Hmmm. Okay, I diddled with cleaning the battery cables as I has a little corrosion on the posts and terminal lugs. Surprisingly it fired right up and I got it parked in its garage bay. The next day I was going to undertake the filming of a How To video using the Mach 1, and found once again it had the Fire No Run condition. I went through the MSD diagnostic steps, and determined the MSD system itself was not the problem. I felt the problem was most likely going to be between the ignition key and the module's small red wire, and after looking at how the prior owner had wired the 6AL I decided to just provide a totally new wiring solution, using a relay to power the small red wire. I most likely had an intermittent open circuit on the wiring feeding power to the 6AL small red wire - as dictated by logic. So, the planned video was replaced by a video on how I fully rewired the small red wire power source for the 6AL. It worked beautifully, and the Mach 12 is not breathing fire once again. I never was able to prove the prior circuit feeding the smaller red wire was open intermittently. I came to that conclusion via the behavior I was seeing. With intermittent, non-duplicatable situations I find there are times I just need to take a stab at the situation, and I get lucky far more often than not. For anyone interested in what how I used a relay to provide power to the small red wire for the 6AL, the link is here: ruclips.net/video/kCfZygdUUds/видео.html
Nice video. I have 2 msd ignition boxes for my nascar. swapped coil from 8250 to 8252 msd blaster, as it was just bogging down under load. now car just starts and dies after 4 seconds. tried both the msd 6tn box and msd hvc box, same exact result. I guess it must be distributor then? It's a brand new coil, and fuel is all good, carb is new. I was going to start checking wiring too first to be sure!!
The distributor really has 2 jobs here unless you have a crank trigger, then it's just 1. It's job is to sense when to fire via the magnetic pick up and points at where to send the spark to. Check the magnetic pick up, and just run through all the normal electrical diag stuff, correct power, good ground, proper connections, and rule those out before going and spending more money on parts that you may or may not need.
Glad to help! The external wiring is pretty simple on these, there's really only a few common points that these have issues and they're pretty easy fixes!
I wish you went into more detail on how you jumped the coil wires to test spark. Could not see what you were doing and you quickly glossed over it. I'm still stuck with a broken boat.
Like this? This is zoomed in a bit from the long video and shows the exact same thing. This is triggering the coil by giving it a signal like the mafnetic pickup would. You need to jiggle it back and forth to make and break contact, holding continuous contact will create one spark. ruclips.net/user/shortsVcUDEGKWqfc?feature=share4
Start with the basics. Solid power and ground, check all the connections at all the points to make sure they're good. Most intermittent problems are issues with connections.
@@SnowFamilyRacing I know you are trying to help, but these boxes just run way too hot. Some people have success while others don't. Ford's duraspark ignition is reliable. I have a box that's been working since 1976.
My car started running bad. Then a fuse burned up for the ignition. I traced a solid black wire from my MSD 7AL to find the nut holding the wire to ground was off and the black ground wire was against the body. So once I put a new nut on it. Boom, started and running fine.
The round blaster coils are not the most reliable. It could be as simple as the boot or the coil could be bad. I use an E style Pertronix Flamethrower coil. It helped my on track consistency and general reliability.
The purple and green pins in the black connector for the magnetic pick up just outside the body of the distributor. Make sure they're pushed into the connector and each other solidly.
Good info... I have an MSD distributor and 6AL ignition module on our 73 Mach 1, installed by the prior owner. It has been a marvelous system (it came with a 6A module, I upgraded to 6AL for the Rev Limiter, just because I felt it was a good idea). Everything went swimmingly for 5 years. In Father's Day, 2023, I brought our 4 Mustangs and Shelbys to a local car show (the 73 Mach 1 won the Best In Show trophy), and ran well all the way to the show and back home.
Once we got home we had 4 cars to jockey around and park them in their various garage stalls. I went to the Mach 1 and found the engine would crank over, and fire up, but as soon s the key was moved to the Run position. Hmmm. Okay, I diddled with cleaning the battery cables as I has a little corrosion on the posts and terminal lugs. Surprisingly it fired right up and I got it parked in its garage bay. The next day I was going to undertake the filming of a How To video using the Mach 1, and found once again it had the Fire No Run condition. I went through the MSD diagnostic steps, and determined the MSD system itself was not the problem. I felt the problem was most likely going to be between the ignition key and the module's small red wire, and after looking at how the prior owner had wired the 6AL I decided to just provide a totally new wiring solution, using a relay to power the small red wire. I most likely had an intermittent open circuit on the wiring feeding power to the 6AL small red wire - as dictated by logic.
So, the planned video was replaced by a video on how I fully rewired the small red wire power source for the 6AL. It worked beautifully, and the Mach 12 is not breathing fire once again. I never was able to prove the prior circuit feeding the smaller red wire was open intermittently. I came to that conclusion via the behavior I was seeing. With intermittent, non-duplicatable situations I find there are times I just need to take a stab at the situation, and I get lucky far more often than not.
For anyone interested in what how I used a relay to provide power to the small red wire for the 6AL, the link is here:
ruclips.net/video/kCfZygdUUds/видео.html
Nice video. I have 2 msd ignition boxes for my nascar. swapped coil from 8250 to 8252 msd blaster, as it was just bogging down under load. now car just starts and dies after 4 seconds. tried both the msd 6tn box and msd hvc box, same exact result. I guess it must be distributor then? It's a brand new coil, and fuel is all good, carb is new. I was going to start checking wiring too first to be sure!!
The distributor really has 2 jobs here unless you have a crank trigger, then it's just 1. It's job is to sense when to fire via the magnetic pick up and points at where to send the spark to. Check the magnetic pick up, and just run through all the normal electrical diag stuff, correct power, good ground, proper connections, and rule those out before going and spending more money on parts that you may or may not need.
Thanks for sharing this video, it really helped me to understand how the MSD works
Glad to help! The external wiring is pretty simple on these, there's really only a few common points that these have issues and they're pretty easy fixes!
I wish you went into more detail on how you jumped the coil wires to test spark. Could not see what you were doing and you quickly glossed over it. I'm still stuck with a broken boat.
Like this? This is zoomed in a bit from the long video and shows the exact same thing. This is triggering the coil by giving it a signal like the mafnetic pickup would. You need to jiggle it back and forth to make and break contact, holding continuous contact will create one spark. ruclips.net/user/shortsVcUDEGKWqfc?feature=share4
Too many problems with MSD. They should have pride and make a good product.
Mine still works 💪 !!!
Got it back in 01!!!!
Nowadays, you'd have better luck finding big foot than a quality part.
Nothing but issues. Sometimes no spark. Can’t figure it out
Start with the basics. Solid power and ground, check all the connections at all the points to make sure they're good. Most intermittent problems are issues with connections.
@@SnowFamilyRacing I know you are trying to help, but these boxes just run way too hot.
Some people have success while others don't.
Ford's duraspark ignition is reliable. I have a box that's been working since 1976.
A great trouble shooting video!
My car started running bad. Then a fuse burned up for the ignition. I traced a solid black wire from my MSD 7AL to find the nut holding the wire to ground was off and the black ground wire was against the body. So once I put a new nut on it. Boom, started and running fine.
Power, ground and easy stuff are always the first to check!
How did you modify the hei dust cap to accept an external coil?
MSD makes a cap to adapt to an external coil. Here's an affiliate link to it: amzn.to/3P3eQVN
@@SnowFamilyRacing Thank You
My blaster coil is arching what could cause that once it starts it shuts off
The round blaster coils are not the most reliable. It could be as simple as the boot or the coil could be bad. I use an E style Pertronix Flamethrower coil. It helped my on track consistency and general reliability.
See any cracks ? Watch it act up in the dark.
What pin exactly my coil is in the cap
The purple and green pins in the black connector for the magnetic pick up just outside the body of the distributor. Make sure they're pushed into the connector and each other solidly.
What is the function of the small white box next to the msd 6al box, thank you for the explanation🙏
It has something to with a points style ignition. Anything with a magnetic pickup doesn't use it.