12VDC Coil for TR-1001 & TR-2001 also fits Teleflex Engine governors. If your coil is black and still working it does not replaced. It is normal for these units to darken with age. When replacing your coil the shaft of the solenoid valve and body should be inspected for any sign of leakage. If you see any signs of diesel fuel the entire solenoid must be replaced. These units have a very low failure rate so insure that the unit is receiving the correct voltage and has a good ground before replacing the coil.