Catalytic Converter: Service and Repair

CATALYTIC CONVERTER

REMOVAL

WARNING: IF TORCHES ARE USED WHEN WORKING ON THE EXHAUST SYSTEM, DO NOT ALLOW THE FLAME NEAR THE FUEL LINES.

1. Raise and support the vehicle.
2. Saturate the bolts and nuts with heat valve lubricant. Allow 5 minutes for penetration.
3. Remove the bolts from the crossover pipe to the catalytic converter connection.
4. Disconnect oxygen sensor wiring.
5. Loosen and remove the nuts from the clamp that hold the catalytic converter to the exhaust pipe flange connection.

NOTE: Do not remove nut from T-Bolt. Only remove nut far enough, so that the T end can be removed from the clamp.

6. Remove the T bolt end of the fastener, from the clamp.
7. Spread the clamp, and remove the catalytic converter from the vehicle.

Fig. 2 Catalyst Removal:

8. Discard the clamp.

NOTE: The catalytic converter to exhaust manifold clamp is not reusable. Always use a new clamp when reinstalling the catalytic converter.

INSPECTION
Look at the stainless steel body of the converter, inspect for bulging or other distortion that could be a result of overheating. If the converter has a heat shield attached make sure it is not bent or loose.

If you suspect internal damage to the catalyst, tapping the bottom of the catalyst with a rubber mallet may indicate a damaged core.

INSTALLATION
1. Position the front pipe onto the exhaust manifold flange connection. Tighten the clamp to 10 Nm (95 in. lbs.) torque.
2. Install the bolts at the muffler and front pipe connection. Tighten the clamp nuts to 27 Nm (19 ft. lbs.) torque.
3. Connect oxygen sensor wiring.
4. Lower the vehicle.
5. Start the engine and inspect for exhaust leaks and exhaust system contact with the body panels. Adjust the alignment, if needed.