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Ok so here is my problem. Installed an msd box on a perfectly starting engine and now it just cranks over until i let the key off of start then it bumps over and starts by chance. once it starts it runs fine. Next problem is when i turn the key off the engine still runs until i push the e-brake in. Im guessing it quits from the inrush current of the brake light somehow. Heres how i wired the box in; took the res wire with no resistor per msd's directions for a mallory unilite distributor and took it to the distributor and a relay to power other things as well as my msd box, power to battery, ground to ground, coil wires to respective posts, yellow wire from r post on starter to positive post on coil, and white wire to green wire coming out of distributor. Any ghost hunters out there?
Last edited by OMB_godfather; 6th-November-2009 at 09:40 PM..
you may need a diode in the alt wire to help shut off engine i had to use one or the engine would not turn off it shows you how to do this in the insructions as for the other problem im not sure
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ya i read the msd troubleshooting section on run-on after i posted that and saw what i had to do. As for the starting thing i still can't find a concrete answer for it.
The wire from the starter gives full 12 volts for starting. (Crank wire.) The resistance wire gives reduced voltage for running to protect the points. (Run wire.) You need to jump the 'crank' and the 'run' wire so you get juice to the MSD in both positions.
The ignition switch doesn't power the coil while cranking. The starter 'R' terminal does. When you let go of the key it returns to the 'run' position and now the coil is powered thru the ignition switch. That's why there were 2 wires connected to the + side of the coil.
http://www.msdignition.com/instructi...pdf?terms=6200 Page 23. The wire from the starter 'R' terminal should be connected to the 12v red switched wire coming out of the ignition switch feeding both the MSD box and the Unilite. Is that how yours is wired?
I wired mine exactly how that shows, except it doesn't have anything on that diagram about the wire coming from the starter. I have that wire going to the positive post of the coil just how it was stock.
The wire from the starter gives full 12 volts for starting. (Crank wire.) The resistance wire gives reduced voltage for running to protect the points. (Run wire.) You need to jump the 'crank' and the 'run' wire so you get juice to the MSD in both positions.
Your original system the coil had 2 wires running to the + positive side of the coil. (yellow & brown resistor wire)
Yellow wire ran from the "I" on the starter solenoid to the + side off the coil.
Brown wire is your resistor wire from ignition switch to + side of coil.
(You said you have already replaced this wire) that is correct.
Both those wires, One from the starter and one from the ignition switch needs to be connected to the MSD box. The Red wire on the MSD box.
The one from the starter (yellow) supplies power while the engine is turning over "START MODE" then when you release the start mode on the key it goes to the ignition power from the switch.
OK i think it just clicked now. I kept reading your replies thinking you were saying the yellow "i" wire goes to the coil + but your saying it goes to the msd box small red correct?
OK i think it just clicked now. I kept reading your replies thinking you were saying the yellow "i" wire goes to the coil + but your saying it goes to the msd box small red correct?
The switched power to the msd box also needs the ingnition bypass wire also.
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Linear Mode
