Section 8 (Engine Cooling System): Radiator: Inspection

WARNING: This page is about a different car, the 2006 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT LOCK PLATE FOR DAMAGE
1. Inspect the lock plate for damage.
  If the sides of the lock plate groove are deformed, reassembly of the tank will be impossible. Correct any deformations with pliers.
  
  Water will leak if the bottom of the lock plate groove is damaged or dented. Repair or replace it if necessary.
  
  NOTE: The radiator can only be recaulked twice. After the second time, the radiator core must be replaced.
  
  Fig 1: Inspecting Lock Plate For Damage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002