Silvershade255

First, I apologize if this has been beaten to death already, been digging all day and am frustrated, I've had my 1978 280Z less than a week.

A PO had used a piece of wire as a fusible link, so I thought to replace it with a proper fusible link. At the same time, I disconnected the battery, positive then negative. I replaced the fuse and connected the battery, negative to positive. I did get a decent spark when attaching the negative. When I attempted to start the car, it turned over but did not start, and the instrument cluster and interior lights did not turn on. I checked and noticed some of the wire going to the negative connection was loose, so I again disconnected the battery and tightened the clamp. When I reconnected, the replaced fuse blew. It was the one in the alternator/ignition relay according to the attached diagram.

Does anyone have an idea of what happened and how I can fix it?

And yes I've thoroughly learned my "if it's not broke don't fix it" lesson.

theramz

I'm sure you have a direct short to ground. So you've got something else mixed up. The po put that wire there in lew of a fuse wire, not safe but it was working. Wiring is the most difficult problem to solve on these old cars. You have to find the short, probably under the dash somewhere.

PredatorZ

Pull all your fuses, replaced the fusible link, reconnect the battery and slowly start replacing fuses, at some point you should blow something, that will most likely be your bad circuit, then you can physically check the wires for exposed copper, and test the connectors/ wires for continuity. You will need a FSM, use the wiring diagrams to help you check out the circuit, see how far you get and check back in with us. You can pick up a cheap test light and volt meter at Harbor Freight, etc, you will need them.

Steve260Z74

You didn't learn the right lesson. The electrical system in your car is broken. You have to watch out for dangerous "fixes" by idiot previous owners. By using the correct part, you could have saved yourself from an electrical fire, losing the car or possibly much more.

With a little electrical knowledge, it's not that difficult to diagnose the electrical systems in these cars.

I'm backed up at work, so send me a PM Thursday to remind me to write up some diagnostic pointers for you.

In the meantime, start looking at the electrical articles on my blog.