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Wire insulation damage under the dash - Bugeye

Fred_Maves

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While inspecting the maze of wires beneath the dash of my Bugeye I uncovered a few wires having had the insulation melted in spots. I suspect that the coiled wire lead to the temperature gauge was the possible source of the problem. Could this be true? If so, is routing the wires well away from the temp lead the solution -or- is there a way to further insulate the temp lead from the possible random contact in the future?
 
That lead doesn't get hot. The gauge works on the pressure of a volatile substance in the bulb, and the lead just carries the pressure. If it is getting hot, there is a real problem, maybe the engine-to-body ground cable is missing.

It's hard to say why the insulation would melt in small areas. Maybe someone was under there with a soldering iron at some point, or something else hot. In any case, if it's short, you can cut out the damaged section and reconnect it with a crimp connection or (my preference) solder it and cover with heat-shrink tubing. I don't recommend taping it, as electrical tape gets gooey and comes loose after some period of time.
 
Steve,
Thank you for your quick response. I am unsure about the ground issue here, but I will certainly make sure to include a ground connection. As for the other possible scenarios, there may have been any number of bumbling DIY guys under there before me.

- Fred
 
There should be a heavy uninsulated cable under the car between the engine/transmission and the body. If it's not there, the high current for the starter will go through whatever path it can, and that often is the tube for the temp sensor. Then, for sure, it will get very hot, maybe melt. It's worth checking to make sure that cable is in place; it's usually connected to one of the transmission bellhousing bolts and is visible by looking under the car. But as long as there is a heavy cable somewhere from the engine to the body, you should be fine. You're probably OK, but still, it's a simple thing to check.
 
Thank you for your definitive example. Being that my car is the culmination of several junked versions, the strap in question must have been removed on the engine/trans. I ended up with. I'm making up a strap as we speak.

Thanks once more.
 
oops A time long ago I managed to short out the rear tail light wires which fried the wiring all the way to the dash switch before I cut the juice. A sad day.. Why the breaker didn't do its job I have yet to figure out
 
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