How to Replace the Thermostat on All 1996 - 2000 Honda Civic LX / Del Sol 1.6L 4 Cyl Engines
Removal & Installation
Fig 1: Removing the hose from the thermostat housing
Fig 2: Removal of the water outlet housing
Fig 3: Pull the thermostat out of the water outlet housing
Fig 4: Remove the gasket from the thermostat
Fig 5: Location of the thermostat air bleed
CAUTION: Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.
- Note the radio security code and station presets.
- Disconnect the negative battery cable.
- Drain the engine coolant into a sealable container.
- Remove the fasteners from the thermostat housing and remove the thermostat.
- Install the thermostat using a new seal. If the thermostat has a small bleed hole, make sure the bleed hole is on the top.
- Apply an anti-seize compound to the threads of the fasteners.
- Reassemble in the reverse order of disassembly.
- Set the heater to the full hot position.
- Locate the coolant bleed valve near the thermostat housing and open the valve 1 / 2 a turn.
- Top off the cooling system and overflow reservoir with a 50/50 mixture of a recommended antifreeze and water solution. and bleed the system to remove any air pockets as necessary. Simultaneously squeeze the upper and lower radiator hoses to help push any captured air pockets out of the system.
- Inspect all coolant hoses and fittings to make sure they are properly installed and if previously opened, close the bleed valve.
- Connect the negative battery cable.
- Install the radiator cap loosely and start the engine. Allow the engine to run until the cooling fan has cycled two times, then turn the engine off and top off the cooling system as necessary.
- Install the radiator cap and inspect for leaks.
- Enter the radio security code.
WARNING: The manufacturer does not recommend using a coolant concentration of greater than 60% antifreeze.
When mixing a 50/50 solution of antifreeze and water, using distilled water may help to keep the cooling system from building up mineral deposits and internal blockage.