Mercury Parts

Mercury Parts Questions & Answers

• Coil Assembly - Ignition
  3W7Z-12029-AA
  Q: How to check and replace ignition coils in different types of ignition systems for the Mercury Grand Marquis?

  A: For the distributor type ignition system (Duraspark II and TFI-IV), start by checking the primary and secondary coil resistance. With the ignition off, disconnect the wires from the coil and connect an ohmmeter across the coil primary terminals. If the resistance is not within the specified range, replace the coil. Next, measure the resistance from the positive primary terminal to the case of the ignition coil. If the resistance is less or more than the specified range, replace the coil. To replace the coil, disconnect the battery cable, detach the wires from the primary terminals, unplug the coil secondary lead, remove the bracket bolts, and detach the coil. Installation is the reverse of removal. For the electronic distributorless ignition (EDIS) system, start by checking the primary and secondary coil resistance. With the ignition off, disconnect the electrical connector(s) from the coil and connect an ohmmeter across the coil primary terminals. If the resistance is not the same for all four tests, replace the coil. Next, connect an ohmmeter between the secondary terminals of each coil pack. If the resistance is not within the specified range, replace the coil. To replace the coil, disconnect the negative cable from the battery, disconnect the ignition coil electrical connectors from each individual coil pack, disconnect the ignition wires, remove the bolts securing the ignition coil, and install the new coil following the reverse of the removal procedure. For the integrated electronic ignition system (COP), follow the diagnosis outlined in section 6. When it has been determined that a coil needs replacement, unplug the coil, remove the retaining bolt, remove the coil, inspect the spark plug, check the coil harness connector terminals, and then replace the coil and reconnect the harness.
• Negative Cable
  E7SZ-14301-A
  Q: How to inspect and replace battery cables for the Mercury Cougar?

  A: Periodically inspect the entire length of each battery cable for damage, cracked or burned insulation and corrosion. Poor battery cable connections can cause starting problems and decreased engine performance. Check the cable-to-terminal connections at the ends of the cables for cracks, loose wire strands and corrosion. The presence of white, fluffy deposits under the insulation at the cable terminal connection is a sign that the cable is corroded and should be replaced. Check the terminals for distortion, missing mounting bolts and corrosion. When replacing the cables, always disconnect the negative cable first and hook it up last, or the battery may be shorted by the tool used to loosen the cable clamps. Even if only the positive cable is being replaced, be sure to disconnect the negative cable from the battery first. Disconnect and remove the cable. Make sure the replacement cable is the same length and diameter as the cable being replaced. Clean the threads of the relay or ground connection with a wire brush to remove rust and corrosion. Apply a light coat of petroleum jelly to the threads to help prevent future corrosion. Attach the cable to the relay or ground connection and tighten the mounting nut/bolt securely. Before connecting the new cable to the battery, make sure that it reaches the battery post without having to be stretched. Connect the positive cable first, followed by the negative cable.
• Seal
  5L8Z-4B416-AA
  Q: How to remove and install a driveaxle oil seal in a Mercury Mariner?

  A: Raise the rear of the vehicle and support it securely on jackstands. Place the transaxle in Neutral with the parking brake off. Block the front wheels to prevent the vehicle from rolling. Remove the wheel(s). Carefully pry out the wheel seal with a seal removal tool or a large screwdriver. Be careful not to damage or scratch the seal bore. Using a seal installer or a large deep socket as a drift, install the new wheel seal. Drive it into the bore squarely and make sure it's completely seated. Lubricate the lip of the new seal with multi-purpose grease, then install the wheel. Be careful not to damage the lip of the new seal. Check the differential lubricant level and add some, if necessary, to bring it to the appropriate level.