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 SUN TDT-12 and SUN VIT InstructionsJump to page : 1 Now viewing page 1 [50 messages per page] | View previous thread :: View next thread |
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wizard |
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Board Moderator & Exner Expert 10K+ Posts: 13045     Location: Southern Sweden - Sturkö island | |||
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| wizard |
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Board Moderator & Exner Expert 10K+ Posts: 13045 Location: Southern Sweden - Sturkö island | I found the instructions on the internet from an article in Polular Mechanics. See below. Does anyone know anything about the SUN VIT? SUN TDT-12 Zero the meter before you turn anything on. the small dial at the bottom of the gauge is used to zero the meter To calibrate it, turn the top left side selector to dwell, connect the 2 test leads together, and adjust the dwell calibrator knob until the needle reads on the bat set line on the right side of the scale. Tach-dwell series. Most tach-dwell meters comes as two in one instruments for measuring engine revolutions per minute and for showing whether the distributor breaker points are properly spaced. The meter electrically measures the angle through which the distributor’s shaft rotates while the points are closed and reads out an average amount for all cylinders. The angle is called the dwell angle or just dwell. Dwell is important because it is the effective length of time the coil has to saturate itself with energy in the form of a magnetic field before the points separate. The coil must use that energy to produce spark. The Sun tach-dwell meter should be zeroed with the zero-corrector button. Then set the tester switches to dwell and calibrate positions. Adjust the dwell-meter calibrator until the meter’s pointer reads on the set line. Use the tach-dwell tester to first to measure distributor resistance. Too much resistance in the primary (low-voltage) circuit keeps the coil from putting out enough juice for good ignition. Connect the test leads on a negative-ground car with the red lead to the coils distributor lead. Ground the black lead. Turn on the ignition and read the meter. If it reads zero, crank the engine a smidgen until the distributor breaker points close and you get a reading. The pointer should then come to rest in the black bar. If it doesn’t, high resistance somewhere in the distributor leads, connections, breaker points or distributor mounting is holding back the flow of electricity. The trouble spot can be pinpointed by moving the test leads, step by step, across each portion of the distributor circuit toward the ground connection. The faulty portion will show high resistance. Correct it before proceeding. If the problem is in the breaker points, replace them. Point cleaning may cause future problems. And a new set of points doesn’t cost that much. To measure breaker-point dwell, connect the tach-dwell tester as before. Turn the selector switch to lobe position matching the number of lobes on the distributor cam – eight for an eight-cylinder car. Start and idle the engine. The meter will read out dwell. Check it against the tolerance for your car. A typical dwell spec for an eight is 26 to 31 degrees; for a six, 35 to 40. Aim for the lower dwell when making a setting. Incorrect dwell indicates improper point adjustment, defective points, or a defective distributor cam. Usually, however, it’s the point spacing. A wider distributor–point setting gives more dwell. A closer point setting gives less dwell. Variation in dwell at different speeds can be seen as a change in dwell reading when the engine is speeded up. To compare dwell at idle with dwell at 1500 r.p.m., set the r.p.m. switch to 8000 r.p.m. and run the engine up to 1500 r.p.m. Then turn the switch back to dwell and note the dwell. Watch it as you reduce the speed back to idle. If the reading changes more than three degrees on some cars (other makers permit more), the distributor has a worn or loose shaft, worn bushings, or worn-out breaker plate. Replace it, but check the specs first. (SUN TDT-12.jpg) Attachments ----------------  SUN TDT-12.jpg (144KB - 371 downloads) | ||
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| rebel |
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Extreme Veteran Posts: 309  Location: Western Colorado | |||
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| wizard |
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Board Moderator & Exner Expert 10K+ Posts: 13045 Location: Southern Sweden - Sturkö island | Thanks' much appriciated! (SUN VIT.jpg) Attachments ---------------- SUN VIT.jpg (144KB - 299 downloads) | ||
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| rebel |
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Extreme Veteran Posts: 309 Location: Western Colorado | |||
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| wizard |
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Board Moderator & Exner Expert 10K+ Posts: 13045 Location: Southern Sweden - Sturkö island | |||
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