TheSamba.com :: View topic - Sudden failure while driving on the highway

Mon Mar 18, 2024 11:47 am

Hello,

My bug is a 1988 Mexi-beetle, 1600 engine, dual port, 12v electric system, it is most of it "stock".

Last Friday I was driving on the highway when suddenly the fuse of the coil snapped and my car went dead. I was on an elevated highway it was scary and hard to reach an exit. Once I went to the ground I called for assistance and a tow brought me home, I was no able to diagnose and repair my car on-site, the fuse kept snapping. I was driving at 60mph and temperature was 30 degrees, the sun light was directly hitting the car. The only thing connected to the fuse I mention is the coil, and the ignition cable. I mention all of this as it may help you to give me a lead on what happened.

At home I manage to stop the snapping fuse by changing points and condenser, I had to set
timing and carb jets from scratch, by now the problem seems to be solved. It drives smoothly.

Nevertheless I would like to know possible causes of this kind of failure.

Thanks in advance!

Mon Mar 18, 2024 12:59 pm

I'm not an electrical expert, but sounds like you had a short in the ignition wire or circuit. You should examine the wires on that circuit to make sure it's not grounding somewhere between the switch, fuse panel and coil. What condition were the points in when you removed them?

Mon Mar 18, 2024 1:10 pm

Is the stock ignition circuit fused? I didn't think so.

Mon Mar 18, 2024 1:34 pm

KTPhil wrote: Is the stock ignition circuit fused? I didn't think so.
True. I sometimes forget that as since I'd added an inline fuse to it on my '72 a few years ago.

Mon Mar 18, 2024 1:54 pm

KTPhil
Quote: Is the stock ignition circuit fused? I didn't think so.
Mine is, I moved the wire of the coil to be protected with a fuse at the fuse box, I use a 16AMP fuse.
vamram
Quote: What condition were the points in when you removed them?
I tested with a multi-meter and found no grounding of the cable that may be generating shorts. The points were "good" and the gap was still maintained when I removed it.