1974 CV16 SS with original 46 year old tach that jumps to 4800 rpm immediately when the key is turned on but the engine isn't started. Tach reading doesn't change once the engine is started. Tach had been working until recently and there's been no recent work performed on the boat, engine, wiring or tach that should have caused this problem. I haven't yet pulled the tach for standalone testing.
Looking for input form someone with the voice of experience on a similar problem......bad tach or faulty wiring? If a bad tach, any recommendations on where to send it for repair? All my other dash gauges are original so I strongly prefer to keep the tach original as well.
