Our Viking 6-burner cooktop ... Model # VGSU160-6b-SS, purchased in October of 1996 ... has two problems.
. PROBLEM 1: Part # 513 (spark switch #3 on the Wiring Diagram, located under the knob that controls the FRONT/MIDDLE burner) is cracked. After I have removed the knob to that burner, I can look down at the part, read the number, and see the crack.
. This burner will ignite, but not in the usual way. To ignite it, I must turn the knob of another burner (to cause sparking) then turn the knob to this burner to cause gas flow. Then the burner functions normally.
. PROBLEM 2: The FRONT/RIGHT burner, when used either alone or in combination with any one of the other five burners, causes either continual or intermittent sparking of the igniters. However, regarding the other five burners, when any one of them is used in combination with any other one of them, there is no continual or intermittent sparking.
. To fix PROBLEM #1, is the only thing I need to do is replace # 513?
. To fix PROBLEM #2, what do I need to do?
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I would start at replacing defective spark switches and cleaning electrodes. Also check for bad insulation on the spark wires.