I attached photos of a two tachs that are identical to the ones I have. The stewart warner one says it needs a sender but one didn't come with it new. So what does it require for one ? . does the sun require an electrical sender ? And does anyone have the proper wiring diagrams?
SW needs the appropriate separate sending unit to match voltage, no. of cylinders, and tach. Looks like the Sun box is laying on installation instructions. Is something missing? Usually switched power, ground, coil- for operation, and maybe power for light from dash lights.
Wouldn't they be more than 5,000 rpm tachs for automobile use and why aren't there any redline needles?
If you take the model # off the box, you can get info. on-line sometimes.Or look up an 800 # for SW and call tech support.I had an old Sun tach I lost the wiring diagram to( only 4 wires,2 I wasn't sure about) I went on their site, matched numbers, and got it working no problem.I was pretty sure of the way it went but didn't want to fry it being" too smart".
These are both replacement tachometers for diesels, probably for a Peterbilt or Kenworth. I believe they have to hooked to a pulse generator.
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