76 corvette stingray has annoying ticking sound around dash area after driving for a little while. What could this be?
Asked by Forrestfire55 Aug 12, 2014 at 02:36 AM about the 1976 Chevrolet Corvette Coupe
Question type: Maintenance & Repair
6 Answers
Either the speedometer cable, the speedometer itself, or the tachometer. If you hear the ticking sound only when moving, the speedometer may be the areas to look at. If you sitting still and you hear the sound, rev the engine to move the tack, and see if the sound goes away or increases in frequency. It that latter is the case, check the tack. Turn off the radio to make sure your not picking up stray electronic signals on the radio. Older cars had noise suppressed capacitors built into the radio wiring that on occasion went out. By the time your Corvette was built, that issue was eliminated. But check it out anyway.
This will explain a "flux Capacitor" BoholMark was talking about. I think his needs replacing, unless he's going back to the future. When a current I flows, it creates a magnetomotive force NI = F which results in magnetic flux Φ. When talking about magnetic circuits, we are always talking about a system of permeable material, so the flux is carried primarily in the core pieces, and divided among them by Ohm's law (or as I like to say, Magnetohm's law). Instead of voltage, we have amperage; instead of current, we have flux; instead of resistance, we have reluctance. Curiously, rather than dissipating power, the system stores energy -- unlike an electric circuit containing resistances! In this example, the left hand core segments, including the segment with the winding, represent a "source reluctance" R1. The center leg consists of two materials, one with permeability μ1 and resulting reluctance R2, and another of μ2 and reluctance R3. The right path is in parallel with the center leg, shunting some flux through R4. So that serves as an introduction to magnetic circuits. You can see they are similar to simple electrical circuits, and they are analyzed the same way. Since reluctance is analogous to resistance, perhaps we can concieve of a component analogous to the capacitor. Replacing V with F, I with Φ, we get: Flux Capacitor Concieved
Thanks California. I consulted with Hoppy and we agreed. Your explanation is as clear as can be.
I had my speedometer completely rebuilt a few years ago after putting in a 5 speed transmission. It had the magnet holder rusted out and it was giving the same sound, and the speed was 15 to 20 MPG off. Good luck, and enjoy your Corvette.