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si2t3m
Hi,

Dunno what is happening but fuse # 9 keeps blowing out. This happens almost as soon as i start the car. i can let it on accessory and everything is fine. As soon as i start the car, #9 goes up in smoke...

# 9 controls the turn indicators, stop lights & reverse lights. I've also wired the fuel pump for my carburators on this fuse. It's been like this for years. Everything was fine. Now this started happening yesterday.

I'm kinda clueless as for how I should trace what is going on.

Cap'n Krusty
Remove the wires "downstream" of the fuse. Put a new fuse in the holder, plug in one of the wires and duplicate the conditions under which the fuse blows. Add the next wire, retest. When you get to the wire that blows the fuse, find out what it powers and fix the problem. Might be well to have a number of spare fuses readily available. The Cap'n
brp914
hopefully, the problem, where ever it is, is constant. Then just operate controls one by one and then look at the fuse until you find the item that blows it. When I had this problem it was signaling a left turn that blew the fuse. I traced the circuit back to the emergency flasher which had a stray tab shorting to the dash frame.

Also look for loose wires like a reverse light wires on the gearbox or engine compartment light wires, etc. Also look where you worked last - fuel pump. I'd also measure the current you got going thru that circuit to see if the fuse is sufficient. good luck
rhodyguy
did you run a power wire directly from the pump to the fuse terminal? i used to have the same setup (don't remember the exact fuse # i used), and had the same problem. i switched to the fuse that powered the cig lighter and that half assed cured the problem. i presume you're running carbs. i suggest you apply andy's jumper wire trick and utilize the proper fuse and relay existing on the engine relay board. adapting the stock pump harness to work with your pump is simple.

k
dflesburg
loose wire at pedal assmbly.
lotus_65
BTDT.

I found my short in the right rear brake light assembly, which led to a complete rebuild on both buckets ('cause I was there).
Turned out every time I wanted to use the brakes that fuse failed, but I didn't connect the dots until after pulling the car half apart and finding it. It's one of those projects that had me cursing my bad luck that whole day of troubleshooting.
The good part about a BS project like that is you really get to know your car...

Anyway, is it vital to run the pump off the fuse box? I'm running off my coil, should I add a fuse in line?
si2t3m
I'm still in there.

I've ran out of 8amp fuses... I'll head back and buy a bunch.

I'll put the fuel pump on it's own (fused) circuit, then i'll check the brake light, turn signal & backup light circuit.

Btw, when i did the conversion i got rid of the relay board. Fuel pump is up front now.

Also, I've ordered a JWest fuse box while i was in there (DWD!!!).
JeffBowlsby
Reverse lights?

Check the wiring on the two reverse light housings in the rear bumper. The screws holding the housings to the bumper actually are a ground, so if they are wired wrong a direct short will occur and pop the fuse.
Dave_Darling
Jeff, those are the license plate lights. Same fuse as the instrument lights--I think that's different from the turn signals and backup lights?

--DD
si2t3m
Found it!!!

A complete day of seach and this morning BAM!

I remove the wire one by one after fuse #9. Came back to black/yellow (to brake switch) wire and that big red/white wire (to emergency flasher switch) that would heat up fuse #9 pretty bad. Took me the day (on & off) to trace.

Then this morning i start rethink of what happend on that day when it all started. Night before had a little rain. Got in the car, started it and put the fresh air blower on. did about a mile and fuse went in smoke. Humm, fresh air blower, fresh air blower...

Fresh air blower was in position 2 this morning... I put it to off, plugged the battery and no more fuse #9 heating up. Put the blower back on and it heats up the fuse. All this should be on fuse #8 but for me it's number that burns... (wtf!!!)

So at least i'm car happy again and stopped looking at that 993.
brp914
so what was the solution? move the fan to #8? Don't use the fan anymore? replace the fan? fix wiring to fan?
si2t3m
Oh, yeah... ehhh... smile.gif

Not to use the fan till I remove the gas tank (again) to install a SS fuel line i just received.

I'm tracing the fresh air blower tomorrow and try to figure where it's shorting.

Today, I repaired my trip gauge (oil press, temp & gas) as i had forgot to install the little rubber isolator for the fuel tank warning light, repaired the horn button, (broken wire), cleaned the rear tail lights, adjusted the fuel pressure regulator & ajusted the carbs.

Did that ever feel good!
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