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TR6 TR6 blowing fuses

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Sumton

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the top fuse blows pretty often. i replace it, drive off, and at some point it blows again. drove maybe 100 miles last weekend after putting in a new fuse. got home ok. started it a few days later and fuse was blown. i have a battery disconnect that i use pretty religiously.

clearly there is a problem. in that circuit are the blinkers, the fuel and temp gages, the wipers, and maybe one other thing according to the wiring diagram. car has been pretty problem free re: fuses for many years. of course other problems . . .

so clearly i have a problem. yesterday i turned on the wipers and the blinkers but no change. i know i need to trace every little circuit involved, looking maybe for a bare wire?

am hoping someone had similar problem and help lead me to a solution.
 
Intermittent shorts are the worst!

Although certainly not a solution, you might want to consider getting a circuit breaker to replace the fuse. They make breakers that fit into the fuse block as a direct replacement, so at least you can get power back after the short clears.
For example https://www.amazon.com/Circuit-Breaker-Reset-Fuse-Clip-CB120-20/dp/B0174FEB1M
Or this style may be a better fit https://terminalsupplyco.com/Store/Product.aspx?pc=CBF-20
(Don't forget that the original fuses were rated by their "instant blow" current, while those circuit breakers are rated by "carry forever". Hence you only want a 15 or 20 amp unit instead of the original 35 amp rating.)

Or another route you can follow while troubleshooting is to temporarily wire an old headlight bulb in place of the fuse. The low beam filament almost always fails first, leaving a good high beam filament which will safely pass 4 or 5 amps but limit the current enough to avoid any damage to the wiring. The bulb will not light, or light only dimly for a small load (like the turn signals alone); but light brightly if you have a short.

Pushing and prodding the wiring while it is live may help narrow down where the problem lies.

If all else fails, you can start adding in-line fuses for each branch of the green circuit and narrow the problem down that way. Since you probably would have noticed if it the problem was associated with the heater or wipers; I'd probably start by doing that for the turn signals and brake lights.
 
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You might want to pull the fuse block and check the underside for some damage in the area of the fuse that keeps blowing.
 
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