Usage:
G3508 (4WD, 2JF, 9TG),
G3512 (4KC, 5JD, 7NJ),
G3516 (3RC, 8LD, 4EK, 5PN)
Use the following procedure to properly test 124-0749 EIS Transformer Group on these engines.
1. Visually inspect the transformer group for any damage, loose screws, connections, etc. Inspect for arcing at the ground spring screw and the tabs for the ground spring. Inspect the teflon extender in the area of the large spacer for evidence of "punch-through" (small pinholes from the spark plug connector through the teflon to the large spacer).
2. Use a multimeter set for "diode check", to verify a .4 to .7 volt drop from the primary pin 1 (A) to pin 2 (B). Pin 1 is on the right when the transformer group is sitting on its ground spring. Reverse the multimeter leads and verify the reading is open.
3. With the multimeter in the 200k ohm range, verify that the resistance from the secondary connector terminal (spark plug connector) to the ground spring is approximately 15k ohms to 20k ohms at room temperature. For earlier design transformer groups (without an internal resistor), the reading will be approximately 15k ohms. For the current design transformer groups (with an internal resistor), the reading will be approximately 20k ohms. If the transformer group is hot, the readings will be up to 5k ohms higher. If the transformer group is very cold, the readings will be up to 5k ohms lower.
4. Verify that the resistance between the ground spring to pin 1(A) measures open on the 20M ohm scale.
5. If the Steps 1 through 4 are acceptable, inspect the secondary connector. If it is corroded or coked with oil, install a 125-0517 Transformer Repair Kit.