Idiot (light) Question

[Tim_Price]

We have no gauges on our 2-1600, just idiot lights. Recently the oil pressure light has taken to glowing dimly when the motor is running. When you first snick on the ignition switch the light glows bright, like it should, but as soon as the engine starts it just glows dimly instead of going out. I replaced the sender and the light itself and still the damn thing glows dimly. Anyone know what this might mean? Please say it's something simple. The engine is only two races old. Thanks.

Tim Price
www.bajabros.com (http://www.bajabros.com)
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[FABRICATOR]

Before you find out why they call them idiot lights...put a pressure gage in that motor and check that oil pressure.

[KitRacer]

Okay I'm gonna go out on a longshot here with my suggestion. It might be the combination of two problems. The only idiot light I have ever had glow on my 1/2 1600 was the Alt. light. I blew a diode out at the 500 and at the 1000. Both times the alternator was still charging and still powering lights, but was proven bad by the Alt. builder and by the glowing light. Anyways, if you have idiot lights with interchangable lenses like my car you might have them on backwards and have a bad alternator. I guess the chances are slim, but I have also put the lenses on backwards, so the chance does exist.

[billymanfroy]

Another stab, Tim. Just trying to help!!!

Is the light ever not on? At what pressure does is the sender supposed to kick on the light? We put a cheap sender in to cut off our fuel pump if the oil pressure drops below 5 lbs, I think. We can either bypass it to prime the carb, or crank the engine to get enough oil pressure to start the pump. (You really should try a pressure guage that tells you what's going on at all times.) That said, if the light is bright (not dim) with the ignition on but engine not running, and then only drops to dim once the engine is running, you either have a bad sender, or a small voltage bleed from the circuit you scabbed it to.

#2: It took us a while to figure out how to wire the battery cut-off switch to actually turn off the engine just by flipping the "emergency" switch. Turns out the alternator was somehow hooked to the ignition circuit and backfeeding the ignition. Silly, but important if you want that emergency switch to actually shut off the engine.

#3: (and most obvious) I have idiot lights as well, and sometimes sunlight, etc. makes them look lit up when they are not.

Good luck!

Billy

[CRAIG_HALL]

Probable not much help but easier to see is the L.E.D. lights-no mistaking them for on or off.

[Tim_Price]

Guys, thanks for the help. I'll be checking out your suggestions this weekend. I want to track down this little problem, but I think I'm also gonna invest in a gauge. I'll report back on what I find.

Tim
www.bajabros.com (http://www.bajabros.com)
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[Tim_Price]

Problem solved. When some idiot (okay, me) installed the new tachometer, he joined the hot wire to the oil pressure idiot light hot wire, so it resulted in the oil pressure light glowing dimly all the time. Jesus maria! I'd fire me from the race team if I could.

Tim Price
www.bajabros.com (http://www.bajabros.com)
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