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!!!HELP!!! MSD blowing fuses???

Jonny-K5

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i installed a used MSD 6A a few weeks ago. works great. this afternoon i was messing with the shifting linkage(other side of engine bay) went to start the truck...nothing. after some head scratching i check the inline fuse to the main power for the ign. box. throw a new one it and fires right up. as soon as i blip the throttle it dies.fuse again. i do this two more times and everytime a blip the throttle it blows. it'll run while idleing tho. what the heck could do this? i didnt touch any wiring. any ideas?
 
anyone?? im clueless on this one. what would make a fuse blow like this? there is no short in the system. i didnt even get close to any wiring. BTW i forgot to mention this is not on my K5, its on a 65 GMC w/ a mid 70's carbed HEI 350.
 
check to see if msd's website has any info on checking the resistance on their ign box.

does your ignition system have a ballast resistor? sometimes they need to be removed. Are your plugs and wires connected properly?
 
Another thing. Does msd require a fuse? Im recalling back now when i installed an aftermarket box on mine. I think it wanted me to hardwire it straight to the battery.
 
are you using the correct guage wiring throughout the system. Running smaller guage can heat up the wiring and blow the fuse. Also very tight bends.
 
i noticed in the manual last night it says no fuse needed. i went ahead and pulled the whole power wire and put a new one in straight to the battery, a little heavier gauge this time too. works fine now.:D

what i dont get is the old setup worked for weeks. then all of a sudden it would pop 30a fuses like it was nothing. owell , at least it keeps running now. thanks for the responses.:waytogo:
 
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