3 main fusables later
 

ok so...back on the forum and i have small issue, i have an 85' gsl with new starter, igniters, fuses, coils, 600ccamp battery, and a new alternator on the way. at first i tried to start it and all i got were my idiot lights and a very pathetic attempt at a turnover...i figured it was my battery and alternator because i had put off getting a new alternator when i should have so i ordered one and set out to get the battery, i was tempted to get the 550ccamp but i said hand me the 600...could this be what is eatting my main fuses? i tried to turn it oer to see if it was really just the alt and batt but as soon as i hooked up the battery i got the white smoke and a killed off main...i figured it was about due because they were stock so i went and slapped in the new one only to have the same issue... on the third after checking my main ground to the tower i popped in the third....well here i am and still have Dann sitting in my lot with no love.

You have a short somewhere on the main. It has to be in the engine bay because inside the car it runs to the fusebox and all of those fuses are rated smaller than the main. Check arond the fusible links to see if a bare wire is touching the chassis or something. Also check at the alt as the later wire at the alt is also connected to that main fusible link. There could also be an internal short in the alternator (have it tested). Also, make sure that the large wire at the alternator is not touching the alternator body at all.

In addition, make sure you don't have you battery cables reversed. That will tend to smoke the main link and also kill your alternator.

How long have you have this problem? If the problem just showed up one day, did you do any work on the car just before it happened?

i sugest you take out the fuseable links, and go with a 2nd gen fuse block.

Battery cable color code
 

It might be a good idea to wrap the positive battery cable with red electrical tape or replace the positive cable with a red jacketed cable to avoid reversed polarity issues.
Why didn't Mazda use the more common color code black negative and red positive? :dunno: