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Ignition Fuse Keeps Blowing

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Old Nov 6, 2011 | 04:34 PM
  #16  
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Ok I'll try all these solutions out tomorrow after work and let you guys know the news, hopefully good news!....
 
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Old Nov 7, 2011 | 02:28 PM
  #17  
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I just went through this on my truck not long ago. Make sure you check all your grounds, additionally double check the alternator wiring and ensure it is hooked up right. It is very easy to hook the alternator up backwards which will eventually cause this to fail. I pulled the grounds off my truck and cleaned them and reinstalled. Then I replaced the blown fusible link and no troubles since. Hope this helps.
 
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Old Nov 7, 2011 | 04:06 PM
  #18  
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Originally Posted by frdlvr35
I just went through this on my truck not long ago. Make sure you check all your grounds, additionally double check the alternator wiring and ensure it is hooked up right. It is very easy to hook the alternator up backwards which will eventually cause this to fail. I pulled the grounds off my truck and cleaned them and reinstalled. Then I replaced the blown fusible link and no troubles since. Hope this helps.
As far as I can see and know the alternator is wired properly, color matched.

Additional notes: today after work I did as I said I would and try out your guys's soloutions, doing so I went to the local parts store bought a 60 amp maxi fuse and a fuse holder to go along with it. Put it on the truck and set power cable from battery to power side of starter solenoid, where this wire/cable also goes, and poof the fuse blows. So whats the problem now?????
 
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Old Nov 7, 2011 | 04:12 PM
  #19  
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I am going to take off the wires from the alternator and try this size of fuse again tomorrow. If it still blows then could my battery itselfs not be giving a good ground?

Everything was left the way it was wired, the only wires I took off were the ones I had to in order to get the engine out of the bay, when the engine went back in I put the wire the same way it came off.
 
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Old Nov 7, 2011 | 06:45 PM
  #20  
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Stop putting a fuse here! I can't keep repeating myself.

If you're blowing a 60 amp fuse with the truck off just by connecting things, then something is drastically wrong. You need to find out where the short is. It could be something as drastic as the alternator being shorted to ground. Never try and solve an electrical issue by upping a fuse size. So far you haven't done anything to indicate to me that you've searched for the actual short. You only seem to be repeating your previous attempts, only to see the same results.

Bad grounds don't make fuses blow. Bad grounds make less current flow than should. Fuses blow because of too much current.

The wiring is simple:

1) The positive battery terminal goes to the battery side of the starter solenoid.
2) The negative battery terminal goes to the engine block.
3) The large output stud of the alternator (marked BATT, A+, etc) goes to the battery side of the solenoid through a fusible link.
4) The A terminal of the voltage regulator ties off the battery terminal of the solenoid (it can also tie past the fusible link from the alternator output, as these are the same potential).
5) The FLD stud of the alternator goes to the F terminal of the regulator.
6) If you have an electric choke, then it connects to the S or STA stud of the alternator.
7) If your truck has an ALT light in the dash, then the S/STA stud of the alternator ALSO goes to the S terminal of the regulator. Keyed power from the cab (downstream of the ALT light) goes to the I terminal of the regulator.
8) If you do NOT have an ALT light, but instead have an amp gauge, then the I terminal of the regulator is left unconnected, and keyed power from the cab goes to the S terminal of the regulator.
9) The alternator grounds to the engine block; the regulator grounds to the inner fender. You can add a ground wire between a regulator mounting bolt and a GND stud on the alternator for good measure.

One final note:

Originally Posted by frdlvr35
It is very easy to hook the alternator up backwards which will eventually cause this to fail.
It won't eventually cause it to fail, something will pop right away, depending on what mistake is made. The system cannot function at all from the start if it's not connected properly.
 
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Old Nov 10, 2011 | 08:00 AM
  #21  
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Originally Posted by fmc400
The wiring is simple:

1) The positive battery terminal goes to the battery side of the starter solenoid. (check)
2) The negative battery terminal goes to the engine block. (check)
3) The large output stud of the alternator (marked BATT, A+, etc) goes to the battery side of the solenoid through a fusible link. (check)
4) The A terminal of the voltage regulator ties off the battery terminal of the solenoid (it can also tie past the fusible link from the alternator output, as these are the same potential). (check)
5) The FLD stud of the alternator goes to the F terminal of the regulator. (check)
6) If you have an electric choke, then it connects to the S or STA stud of the alternator. (x - manual choke)
7) If your truck has an ALT light in the dash, then the S/STA stud of the alternator ALSO goes to the S terminal of the regulator. Keyed power from the cab (downstream of the ALT light) goes to the I terminal of the regulator. (x- no alt light)
8) If you do NOT have an ALT light, but instead have an amp gauge, then the I terminal of the regulator is left unconnected, and keyed power from the cab goes to the S terminal of the regulator. (check)
9) The alternator grounds to the engine block; the regulator grounds to the inner fender. You can add a ground wire between a regulator mounting bolt and a GND stud on the alternator for good measure. (check)
Additional truck now has power everywhere tries to start, cranks and all but not fully turn over.??
 
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Old Nov 10, 2011 | 08:42 AM
  #22  
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What changed since last time? Am I supposed to assume you rewired everything according to the instructions above? Did you fix the first issue, and now this is a new issue? Or are both happening? One thing at a time...
 
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Old Nov 10, 2011 | 09:27 AM
  #23  
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Originally Posted by fmc400
What changed since last time? Am I supposed to assume you rewired everything according to the instructions above? Did you fix the first issue, and now this is a new issue? Or are both happening? One thing at a time...
X2 Glad you have the patience to hang with him. Actually surprised that adding bigger fuses hasn't shown the location of fault with smoke. Wiring itself was designed to handle a specific load. Increasing rating of fuse link or fuse doesn't make the wiring handle more current. Anyone working on wiring needs a multimeter and basic knowlege on how to use it.
 
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Old Nov 10, 2011 | 01:43 PM
  #24  
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Originally Posted by fmc400
What changed since last time? Am I supposed to assume you rewired everything according to the instructions above? Did you fix the first issue, and now this is a new issue? Or are both happening? One thing at a time...
What I did was disconnect the alternator wires, place a normal 40 amp fuse in my inline fuse holder. Place one wire back on at a time till I possibly came by the problem, and I did not come by any problem connecting the wire(s) back on the alternator . After all the wires were back on I took a look and seen what was left, happenes to be one single wire which is also the colprate, this wire was attached the ground side of the alternator and ran to the starter solenoid, didn't attach to it itself but behind its braket, so it was between the braket and the inner fender. So it was trying to ground and power at the same time to my understanding. So first problem resolved, second/new problem is now it will crank and light up just won't turn over.
 
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Old Nov 10, 2011 | 08:21 PM
  #25  
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Okay, so my understanding is that you (finally) traced out the wiring, found a short, fixed the issue, and can connect things back. Got it.

You're still not following my advice to replace the fusible link with the correct AWG size, and instead you've arbitrarily chosen a fuse size without considering the current rating of the wiring you're trying to protect. I'm done repeating myself there; whatever happens happens.

So now the engine is cranking, but doesn't start? Check for fuel and spark.
 
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Old Nov 11, 2011 | 08:34 AM
  #26  
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Originally Posted by fmc400
Okay, so my understanding is that you (finally) traced out the wiring, found a short, fixed the issue, and can connect things back. Got it. - Yes, I traced the wiring problem.

You're still not following my advice to replace the fusible link with the correct AWG size, and instead you've arbitrarily chosen a fuse size without considering the current rating of the wiring you're trying to protect. I'm done repeating myself there; whatever happens happens.

So now the engine is cranking, but doesn't start? Check for fuel and spark.
I did follow your advice and that's how I solved this first problem. THANK YOU FOR YOUR HELP WITH THAT!! the wire size, AWG, on the inline fuse holder is the proper size. The fuse I placed in was one that the mechanic recommended. Yes, that's is the new issue it will crank but not turn over. I checked for fuel the pump pumps but I don't think the carb is getting the fuel and the lines are new. I'll check for spark the next time in at the truck. If it has all that what else could it possibly be? THANKS AGAIN!!!
 
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Old Nov 28, 2011 | 02:07 PM
  #27  
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Truck has no spark. Has fuel. Bought new ignition coil, ignition control module and voltage regulator. Truck cranks but nothing there, it wants to kick over but can't, no spark.
 
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