Blowing Fuse Links

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I found this posted and thought it might be interesting
i. I'm curious if anyone else has this problem and what they did to fix I. On the starter solenoid their are two fusible links actually 3 one is one wire off the solenoid and splits to two fusible links and then there is a single fusible link. I unwrapped the wire harness and chased the lines down to their connection . The single fusible link is my problem. Running from the solenoid to the alternator. Their is no open spots in wiring or grounded out anywhere. And happens sporadically. No patterns, just whenever it happens. When I'm in-car driving or in idle . My car starts runner Ng horrible and the volts go from 13.8 - 14.1 volts . In 3 to 4 minutes the battery is at 6 volts and the car does. The fusible link melts and breaks and instantly the car's battery drains dead and the car won't do anything but click click click. Replace the fusible link and sometimes it runs again other times the fusible link burns again and again. Tested the alternator and starter both checked out fine. Replaced the battery cables pos. And negative ran me wires to the alternator to solenoid. Still have the problem. Replaced the alternator last night and only to find the alternator is no good , a brand new alternator, no good. Frustrating. If anyone has any ideas please let me know. Can't take the car my anywhere otherwise I have to tow it back home. Almost 90 %of the time. What can I do to fix my problem, what is creating it to happen? Need help please. Electrical is not the best part I'm good at on car. Everything's else I can handle very well. Please help me. What to do...

I think Id start by
buying a shop manual if you don,t own one


www.batterycablesusa.com

https://ceautoelectricsupply.com/
https://www.ecklerscorvette.com/cor...omLUocYwxVeslWZNsORoC16cQAvD_BwE&gclsrc=aw.ds

25-360026-1.jpg


then by pulling trouble codes and verifying the starter is correctly wired,
if it is Id start with testing the battery under load, and if required,
swapping to a new battery and possibly a new
gear reduction starter and remote solenoid
if the battery and alternator test ok, both at idle and under load,
and your melting fuse links regularly,
and your battery cables, pos/neg are new and recently replaced,
your starter is obviously drawing excessive amps at times
if anyone else cares to chip in info here please do so
ID suggest you add a separate electrical ground strap
212100_primary_450px.jpg

from the engine too the cars frame also


read these links



http://garage.grumpysperformance.co...-ok-but-key-won-t-start-car.12496/#post-63024


http://garage.grumpysperformance.com/index.php?threads/problem-with-starter.1646/
 
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Sounds like the alternator is wacky bridge/diode trio or diodes when you say it goes from 13.8 to 14.4 and then it burns the fusible link and then battery dies.

Check grounds from engine to frame and alternator to engine
Check battery---load test and get readings---have to recharge before restarting car?

No alternator should go to full charging like that even if it was under full load--every electrical item on car turned on. Malfunctioning regulator would.
 
When I re did my Vette I put a buss bar from an electrical panel and grounded it from the battery , the frame and to the engine and run a separate ground wire to everything I could find while I was re wiring it
 
the guy with the wiring issue posted this
Well after doing several test test with digital tester. I replaced the alternator, battery , power cable from battery to the starter. Installed a new starter, did new ground cable from battery to engine Block. Ground cable frame to engine Block motor to alternator housing. Put 2 wire clip on and single 10 Guage wire from start or to fuse to alternator. After all this the car still was having major issues. Volts kept jumping . Went from 13.9 volts down to 10.5 volts and then would jump back up to 24 or up to 36 volts from alternator. After several hours checking each wire again several times. I put tester onto the fusible link off of starter to 10 Guage wire to alternator with clips to tester. I noticed everytime the problem started to jump the volts around the fusible link was taking a hard hit at the splice connection. To the point it was causing it to burn the fusable link everytime the spike was high. This is my first corvette but have built over 300 hot rods and this is the first time I have ever seen a fusible link on the 10 Guage wire from starter to alternator. On any car of Chevy I have built. The more I was watching the numbers when they would jump around the fusible link would take a hard spike hit and on the 48 volt read out would cause the fuse able link to burn. So I tested a thought on this. I ran a new 10 Guage wire from the starter to the alternator added connector fittings needed to attack the line in place. ( For the record ) the start or still has two fuseable links from starter to the main connectors 8n side the vetted to fuse box and 2nd power supply. Driver side has three more fusable links in battery power wires from electric fan , electrical fuel pump relay , and ignition switch horn , and light relay power supplies. So all the main wire power lines are all fused. The fusable link on the starter to alternator wire is completely unneeded. I found with the wire splice at that location the volts were jumping at that splice. Bad enough to krep burning the fusable link out. When I ran the new 10 Guage wire and connected directly to the starter and to the alternator with no fusable link. I then had no resisted center at all. On either the possative or negative side of the alternator or battery. Not even the .03 it did have before hand. With digital tester in place I started the car and, a smile came across my face. The numbers are perfect , the volt gauge snide the car read 13.9 volts , the red square idiot light was off , the car was running perfect , no idle change and esting the alternator and battery was perfect steady 13.9 volt out put. Checked the wire at starter and it was not jumping or anything perfect 13.9 volts on the wire. Have started and stopped the car over 200 times , test drove the car , and amazing difference the car runs and the power is their in it now. Hit the gas and it grabs and goes. The dash lights are bright and head lites are bright and function perfectly . The dash digital is not jumping around or freezing up , it works perfectly. All instrumpet panels ,guages,and all work flawlessly now. I wired it as I have wired all my Chevy vehicles in the past. A single 10 Guage wire starter to alternator without a fusable link in that line. And it worked. The wiring in the car has enough protection needed for power lines run. The splice in that line to a fusable link caused a great issue for what ever reason. Causing it to spike and jump at that splice. Causing it to burn up the fuse on that line at different times it would do it. Sine taking out that fuse and splice I have resolved every problem and concern I had going on with my car. Been a few days and stI'll is running beautiful as can be. Not a single issue with any of the electrical now. I know Chevy placed their splices back in the day at spacific locations in the car due to the volt at the splice it would take on.
My opinion is that that fusable link is not needed and a major problem creating a splice connection in that line. Causing it to spike and burn the fusable link. Causing hell on the wiring to the car when it melts down. I have never put a fuse on that line before ever , and by removing it. It removed a splice connection not mentioned to be their taking abuse from electrical connections in the sytem. Anyways the car is running great , sounds good , runs great , and has some up and go to it now. Thank you for the help I did find a problem with the starter as well open ground , not shutting off after engage to start. But didn't resolve my issues completely.
Thanks again for the help.
Know working on the heater motor , door hinge ,spring and bushing both doors and trying to wire in the sensor to radiator to control the fan from running all time and to only when it needs to run at desired tempueture. Then will be closer to having it done right
 
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Chasing wiring issues can be a real pain but it looks like you found your main problem
 
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