fuse #9 snapping before car can start

[914orrust]

I'm at my wits end.

I finally got my car back from the shop with a rebuilt engine and I can't take it out for a spin because the dang #9 fuse snaps as soon as I turn the key.

I realize there is probably an errant ground somewhere but what would be the likely cause for it to snap at the first turn of the ignition key?

I checked the connections in the fuse area. They all look fine. I checked the connections behind the fuel/temp gauge. They appear ok. Is there another spot I should investigate?

Thanks, in advance, for all your help!

[RandyLok]

Sounds like there is a direct short somewhere. Fuse 9 is the fresh air fan. Does it still snap with the fan off?

If so you'll have to trace circuits looking for a wire with bad insulation that is grounding out, or a part that's shorted internally. Perhaps put a multimeter from power connection at each place to ground, checking ohms/continuity for a short.

Besides fresh air fan, here are some more potential circuits to look at in the fuse 9 track:

Reverse switch on tranny (Troy just had this... fuse 9 was blowing. He found water in the reverse switch.)
Tail lights, tach, fuel gauge, oil temp gauge, voltage gauge, alternator idiot light, low fuel idiot light, oil pressure idiot light, clock.

[sammyg2]

If a fuse blows, try and find the reason before replacing the fuse. If you keep trying new fuses, eventually something else could melt besides the fuse.
get someone who is talented in the ways of sparktricity to trace the ground and eliminate the source, otherwise you are risking your wiring harness and maybe the car.

[John Rogers]

You might want to ask the shop how they ran it when the fuse keeps blowing? Fuse 9 also feeds the backup light switch and brake light switch so one of them could be shorting?

[Kevin Powers]

stock f.i or carbs? if carbs, where is the power pulled for the fuel pump?

k

[914orrust]

Its carbs and to answer your question about the fuel pump... I don't know. I'm going to take it back to the shop that rebuilt the engine, I'll ask them to take a look there.

BTW - I found they didn't hook up the reverse lights and broke the little nubs. I hoped fixing them would cure the problem, but, alas, it did not.

I'll let you all know how this turns out. It might be useful to someone someday.

thanks for all your advice!

[Kevin Powers]

does the pump run after you turn the key to the first position, even when the fuse blows? the carb conversion was performed during the rebuild? if so, my guess is they ran a wire to the fuse panel. i blew fuses repeatedly doing this. you should go to the classic thread section @ 914club and look up andy's jumper wire trick for powering the pump. his method lets you use the proper fuse and relay located on the relay board in the engine compartment with about 4" of wire and 2 connectors. btw, if your pump makes a rattling sound when you turn the key, it a facet type. caca. get the self regulated rotary style from cbperformance. hope this helps.

k

[914orrust]

The fuel pump does run as soon as I turn the key to the first position. It makes a clicking sound which I think is what you were referring to. I will look up the thread and give that a try before I take it into the shop.

thanks again for the help.