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RLW
09-03-2002, 03:11 PM
When ignition switch is turned on, oil pressure gauge all the way to the right, volt meter stays at zero, fuel gauges stay at empty, bilge pump does not operate, tach does not work. Engine starts right up and runs great.
Anyone have a clue? Fuse, short, broken wire?
Need help.
Thanks RLW

Jordy
09-03-2002, 03:16 PM
I would look for a power wire that comes off your key switch and runs to a fuse box, buss bar, or something to feed all of your gauges and bilge pump. Does the bilge normally run with the key off? If not, I would look at wiring in a seperate circuit for it so that it will in the event you ever want to leave it beached or docked overnight. That way you could leave the bilge pump on and take the key with you. Sorry for the long post, but that is what I would look for.
jordan

Oldsquirt
09-03-2002, 04:41 PM
RLW, its typical for the gauges to have both the power supply and ground circuits "daisy-chained" meaning that they run from gauge-to-gauge rather than tapping off of a common line.
Since your oil pressure gauge functions, although incorrectly, your power circuit should be OK from switch to fuse(if used)to that gauge. It reads full pressure because something is grounding the "S" circuit. (I can't help but wonder if someone was working back there and mixed up a couple of wires, specifically the ground and oil sender leads).
Get out the voltmeter and check for power and ground at the "I" and "G" terminals, respectively, at each gauge as well as at the bilge pump switch.
Personally, I'm betting you find a fault in the ground circuit since bilge pumps are generally wired to an "always-on" power source.
Good luck and let us know what you find.

RedneckTunnel
09-03-2002, 06:59 PM
Check the ground. It sounds like a dead short to me ie. hot and ground mixed or touching at or near the gauge not working. just my two-cents

502procharger
09-03-2002, 07:22 PM
same thing happened to me a few yrs back. turned out to be a bad ground. i nver found out where it went bad i just ran a new ground. check that first. as stated it may also be a short but i would bet on a bad ground.

bordsmnj
09-04-2002, 12:33 AM
also, if you correct the short you'll still more than likely need to replace some fuses.

shockwaveharry
09-04-2002, 02:05 PM
90% of electrical problems in cars are due to a poor or open ground. That is the first thing I would check for. There is a tool called a "power probe" that is made for just this type of thing. Think of it as a smart test light. When you probe a wire or terminal, not only will it tell you if that is a power (+) circut or ground (-) circut, it also allows you to supply power or ground to the circut via a switch on the probe. It's the difference between guessing what the problem is and actually knowing. everyone who works on their own stuff should have one.