Electrical/Coil/MSD question - duhhh!
Thread Starter
Safety Car
Joined: Jun 2002
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From: Pearland TX
St. Jude Contributor
Electrical/Coil/MSD question - duhhh!
Some help please(MSD Users)...
I've got basically a dead battery, so while it is charging overnight I need some help to make sure I have the MSD wired right before attempting to fire up this new motor. Here's my ignition set-up so you know what I am working with:
MSD-6A, MSD Pro-Billet HEI Dist Pt#8572 w/ Vacuum advance & MSD Blaster 2 coil
Someone please tell me if this is the correct wiring:
1)Heavy red wire from MSD to starter positive.
2)Heavy black wire from MSD to frame(ground)
3)Small red wire from MSD to ignition switch
4)Small orange wirefrom MSD to positive side of coil
5)Small black wire from MSD to the negative side of coil
6)Small white wire from MSD to ???. Right now I have it connected to the old positive wire coming out of the firewall that was hooked to the coil. This one I don't have a clue.
I tested the MSD box itself and it appears to be working fine with 12volts coming out on the red wire to the ignition switch. And a test of the box itself for fire on the white wire shows a jump(spark) into the distributor coil wire.
And while I am at it, what is the best way to prime the fuel line/pump & fill the bowls on the carb(Aftermarket Holley 750 4150) so that I have constant fuel when I turn it over.
Thanks....
[Modified by bgrice, 5:07 PM 8/10/2003]
I've got basically a dead battery, so while it is charging overnight I need some help to make sure I have the MSD wired right before attempting to fire up this new motor. Here's my ignition set-up so you know what I am working with:
MSD-6A, MSD Pro-Billet HEI Dist Pt#8572 w/ Vacuum advance & MSD Blaster 2 coil
Someone please tell me if this is the correct wiring:
1)Heavy red wire from MSD to starter positive.
2)Heavy black wire from MSD to frame(ground)
3)Small red wire from MSD to ignition switch
4)Small orange wirefrom MSD to positive side of coil
5)Small black wire from MSD to the negative side of coil
6)Small white wire from MSD to ???. Right now I have it connected to the old positive wire coming out of the firewall that was hooked to the coil. This one I don't have a clue.
I tested the MSD box itself and it appears to be working fine with 12volts coming out on the red wire to the ignition switch. And a test of the box itself for fire on the white wire shows a jump(spark) into the distributor coil wire.
And while I am at it, what is the best way to prime the fuel line/pump & fill the bowls on the carb(Aftermarket Holley 750 4150) so that I have constant fuel when I turn it over.
Thanks....
[Modified by bgrice, 5:07 PM 8/10/2003]
Drifting
Joined: Sep 2001
Posts: 1,427
Likes: 1
From: Boxford Mass
Re: Electrical/Coil/MSD question - duhhh! (bgrice)
I have the same setup as you -- my white wire is open. I'll check now for you...
Yes, my white is not in use. It appears to be used for an amplifier feed from electronic ignitions or something. MSD has all the wiring diagrams on their website. All of your other wires look good (orange color to distributor though)
[Modified by Jack71, 6:26 PM 8/10/2003]
Yes, my white is not in use. It appears to be used for an amplifier feed from electronic ignitions or something. MSD has all the wiring diagrams on their website. All of your other wires look good (orange color to distributor though)
[Modified by Jack71, 6:26 PM 8/10/2003]
Thread Starter
Safety Car
Joined: Jun 2002
Posts: 4,844
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From: Pearland TX
St. Jude Contributor
Re: Electrical/Coil/MSD question - duhhh! (Jack71)
Jack71...
Thanks for the quick answer. I've got 4-5 different wiring diagrams that came with the ignition/distributor and the smallest wires(black/orange) definitely go to the coil as they already have the eye outlets that fit and all of the pictures show them going there. The white wire? I didn't know if there needed to be some loop into the distributor or not. There is a quick disconnect out of the bottom of the distributor that is not being used and one of the diagrams says this:
MSD SYSTEMS Installing to Points/Amplifier Style Ignition
White Wire - Connect to wire from points or electronic ignition amplifier(original coil *negative* wire).
And another diagram shows not using it at all.:confused:
Also... with the ignition *ON*.... should there be voltage going into the coil or will that not happen until the engine is running? I put a voltage meter(DC current) on the connectors of the coil with the ignition switch *ON* and nothing.
[Modified by bgrice, 6:13 PM 8/10/2003]
Thanks for the quick answer. I've got 4-5 different wiring diagrams that came with the ignition/distributor and the smallest wires(black/orange) definitely go to the coil as they already have the eye outlets that fit and all of the pictures show them going there. The white wire? I didn't know if there needed to be some loop into the distributor or not. There is a quick disconnect out of the bottom of the distributor that is not being used and one of the diagrams says this:
MSD SYSTEMS Installing to Points/Amplifier Style Ignition
White Wire - Connect to wire from points or electronic ignition amplifier(original coil *negative* wire).
And another diagram shows not using it at all.:confused:
Also... with the ignition *ON*.... should there be voltage going into the coil or will that not happen until the engine is running? I put a voltage meter(DC current) on the connectors of the coil with the ignition switch *ON* and nothing.
[Modified by bgrice, 6:13 PM 8/10/2003]
Drifting
Joined: Oct 2000
Posts: 1,825
Likes: 56
From: Shawano WI
Re: Electrical/Coil/MSD question - duhhh! (bgrice)
The white wire is the trigger wire if you are not using a MSD distributor. As you are using the 8572 tach drive distributor you will use the 2 wire plug to connect the box and the distributor. The white wire is not used in your situation.
Thread Starter
Safety Car
Joined: Jun 2002
Posts: 4,844
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From: Pearland TX
St. Jude Contributor
Re: Electrical/Coil/MSD question - duhhh! (Pete79L82)
Pete,
Given what you said.... that I attach the quickconnect magnetic pickup harness(supplied) to the MSD ignition and on the other side the distributor, should I find voltage to the coil with the ignition switch on? And of course I just wrap up the white wire and put it in the harness with the rest of the wiring.
Thanks again for the help guys. An electrical wizard I am not. :cheers:
Given what you said.... that I attach the quickconnect magnetic pickup harness(supplied) to the MSD ignition and on the other side the distributor, should I find voltage to the coil with the ignition switch on? And of course I just wrap up the white wire and put it in the harness with the rest of the wiring.
Thanks again for the help guys. An electrical wizard I am not. :cheers:
Advanced
Joined: Mar 2002
Posts: 92
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From: Denham Springs La
Re: Electrical/Coil/MSD question - duhhh! (bgrice)
For what it's worth, you may want to run a dedicated ground to the battery from the MSD box. I have experienced some weird happenings on my race car because of a ground. I eventually ran a dedicated ground to the battery. The other item to be aware of. If you accidently hook up a charger backwards or battery cables with the ignition on you will fry your MSD box.
The voice of experience speaks volumes
IETEK :chevy
The voice of experience speaks volumes
IETEK :chevy
Thread Starter
Safety Car
Joined: Jun 2002
Posts: 4,844
Likes: 0
From: Pearland TX
St. Jude Contributor
Re: Electrical/Coil/MSD question - duhhh! (IETEK)
IETEK,
Thanks for the information. This is the first street car I have put an aftermarket ignition in, so the last thing I want to do is roast the MSD box before it ever makes a spark. I had a 7AL on a Super Gas doorslammer with a Pro Coil years ago, but the wiring was alot simpler given what little wiring there was and I had someone wire the car for me.
I still haven't found anyone who could tell me if I should have voltage to the coil with the ignition in the *ON* position. If so, it would give me a warm fuzzy feeling that I am on the right track that it's my timing and not something else that might impeed starting this thing up.
Again... thanks.
Thanks for the information. This is the first street car I have put an aftermarket ignition in, so the last thing I want to do is roast the MSD box before it ever makes a spark. I had a 7AL on a Super Gas doorslammer with a Pro Coil years ago, but the wiring was alot simpler given what little wiring there was and I had someone wire the car for me.
I still haven't found anyone who could tell me if I should have voltage to the coil with the ignition in the *ON* position. If so, it would give me a warm fuzzy feeling that I am on the right track that it's my timing and not something else that might impeed starting this thing up.
Again... thanks.
Melting Slicks
Joined: Nov 2001
Posts: 2,659
Likes: 7
From: Katy (Houston) TX
CI 7-8 Veteran
Re: Electrical/Coil/MSD question - duhhh! (bgrice)
I still haven't found anyone who could tell me if I should have voltage to the coil with the ignition in the *ON* position. If so, it would give me a warm fuzzy feeling that I am on the right track that it's my timing and not something else that might impeed starting this thing up.
Again... thanks.
Again... thanks.
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Burning Brakes
Joined: Jul 2000
Posts: 1,162
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From: Beaverton, OR
Re: Electrical/Coil/MSD question - duhhh! (tshort)
Did Mark tell you to do the single or dual start in procedure? I did the dual which consisted of break-in for 20 minutes at something like 1800rpm. Drain oil, replace filter and do it again for 20 minutes. Drain oil, replace filter and run under 4Krpm for 500 miles. Drain oil & filter and break-in is over. I'm 50 miles away from ending break-in but I'm in the middle of replacing the fuel pump and installing a pressure regulator. Should be done in about a week and a half.