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msd problems/ need electrical help!!!!!

  • Thread starter Thread starter PrimerIsFaster
  • Start date Start date Mar 16, 2004
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PrimerIsFaster

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Sep 3, 2002
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Mar 16, 2004
#1
  • Mar 16, 2004
  • #1
Ok i've burned out 3 MSD 6AL's in the past 2 weeks, i got a 91 carburated coupe, i'm running a MSD pro billet distributor, MSD 6AL, and MSD blaster 2 coil. I also have a 130amp 3g alternator. now here is the problem, all 3 boxes burned up within a few days of each other. now i've been told by a local that i'm running too much voltage to the boxes, i checked my voltage and it's 14.65 with the car running, 12.30 with the car off. MSD says that their boxes can take up to 18.v so i dont know whats up with that. as far as the wiring for the box, i got 12 gauge positive going to the positive terminal on the starter relay, 12 gauge ground bolted to the chasis and the paint was scraped of the ground area, 14 gauge ignition signal running to the ignition key, and the coil and distributor wires are 14 gauge and are hooked up right. like i said the car runs perfect for a few days and then it just wont start and when i check the box its dead. i thought maybe it was the voltage regulator on the alt. i bought another 3g and installed it, it read 14.70v with the car running. so its not that. if anyone could give me any ideas on what to check i'd apreciate it!!!!!
 

sldghmr

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Jun 30, 2003
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Sil Sprg, MD
Mar 16, 2004
#2
  • Mar 16, 2004
  • #2
Did MSD ask to see one of the boxes back? I'd send them one and see what they say is the cause of death. I've had a MSD for a long time and just about 3-4 months ago my altenator just about caught fire. Don't have a clue to why, but bought a new one and everything has been fine since then. Still want to know why we have wierd (sometimes unexplainable) electrical problems w/our cars. Maybe you should try fusing the power line into the MSD box?
 
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PrimerIsFaster

New Member
Sep 3, 2002
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Mar 16, 2004
#3
  • Mar 16, 2004
  • #3
well yeah one of the boxes went back and they said it was in fact caused by too much voltage, even though my voltage reads 14.65 with the car on and they say their boxes can take 18. volts
 

jrichker

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Mar 16, 2004
#4
  • Mar 16, 2004
  • #4
Per my reply to your post in 5.0 talk, check the grounds. If you have a 3G alternator, you need a 4 gauge ground from the engine block to the battery chassis ground. Bad grounds will cause voltage spikes that can damage electrical equipment.
 
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