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Hello everyone, newbie here. My son and I bought a 1970 LT1 4-speed convertible project car for him to work on. Has some electrical issues to clear up, like signals and tail lights before it is road worthy. One issue was a new throwout bearing project that we finished, but putting everything back together, I connected some wires that weren’t connected and once I installed the battery, the interior lights came on, slowly faded, and went out. I smelled some plastic burning but couldn’t pinpoint where it was coming from. Now with the battery connected, there is no power to the car at all. Car doesn’t start, no lights, nothing. Car started fine before. What I would like to know is where should I look first. The car started and ran fine before. I think one wire I connected was to the reverse switch on the tranny. There is 12v to the starter. Thanks and I will post all the progress, Ron.
Last edited by 67goat; Aug 29, 2020 at 04:58 PM.
Reason: Typo
Peterbuilt hit the nail on the head. Start there. Then before reconnecting those wires. Find out what there for, and test those circuits with an ohm meter. There's a dead short to ground somewhere on the car and it does sound like you melted the fusable link.
Thanks for the advice. All the grounds were checked and cleaned up, so we can rule that out. Now when you say fusible link, is that just a glass fuse spliced into the wire? What do they look like? Thanks again.
A fusible link is just a small section of wire that is undersized, and designed to melt if over-loaded. Used in places before the fuse box that need protection. Like alternator, starter, etc. Should be listed on the wiring diagram. I think they are just wrapped into the main harness. To find one test both ends of the wire for continuity. Then look for a section which from the factory has two large rubber bulging "splice" sections so you can easily identify it. Must be replaced with the correct size to prevent fires.
Hers a pic of one on a chevy. OEM GM Fusible link with two rubber splice sections.
Here is a pic with it noted on the wiring diagram. The smaller 14 ga Brown section in the larger 12ga red starter wire is a fusible link. There are more on the horn relay.
Last edited by leigh1322; Aug 31, 2020 at 05:54 PM.
There are a couple of fusible links leading to the starter which feed power to a multitude of places.
They have the big round cylinder of black rubber which has a crimp connector inside... test for continuity with the battery disconnected and if you have no power through it, replace them... the size (gauge) of the fusible link wire is indicated in the ASSY MANUAL.
WHAT EVER YOU DO... DO NOT STRAIGHT WIRE IT... BUY FUSIBLE LINKS AND USE A SOLDERLESS connector.
Thanks for the advice. All the grounds were checked and cleaned up, so we can rule that out. Now when you say fusible link, is that just a glass fuse spliced into the wire? What do they look like? Thanks again.
It BURNT UP because it went to GROUND.
Whatever was previously disconnected may have had a short OR you could have pinched a wire when re-installing the trans/bellhousing etc. There are a couple of wires on 4 speeds which run down the trans/bellhousing... ALSO if the car STILL has Transistorized ignition on it, and you disconnected any of that wiring it connects different than a STD ignition.
You can buy fusible links at Oreillys or almost any auto parts store. OR buy a roll or two of it and repair everyone's harnesses.
Last edited by firstgenaddict; Sep 3, 2020 at 09:02 PM.
On my '71 BB, there's a black ground wire that is under the outside starter mounting bolt. Sometimes it is under a bell housing bolt. Make sure it didn't get installed under the battery connection at the starter.
Mine is under the outer starter mounting bolt like shown in Alan71's photo:
70 LT1 no power
