Toyota Pick-ups/Land Cruiser/4Runner 1989-1996

Thermostat

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REMOVAL & INSTALLATION



See Figures 1 though 8

  1. Drain the cooling system.
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CAUTION
When draining coolant, keep in mind that cats and dogs are attracted by ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain coolant into a sealable container. Coolant may be reused unless it is contaminated or several years old.



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Fig. Fig. 1: On, 3VZ-E engines the thermostat is located in the waterpump

  1. On 3F-E engines, disconnect the 2 vacuum hoses from the Bimetal Vacuum Switching Valve (BVSV), the cold start injector time switch wire and the water temperature switch connector.
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Fig. Fig. 2: Exploded view thermostat and housing on the 1FZ-FE engine



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Fig. Fig. 3: Exploded view thermostat and housing on the 2RZ-FE and 3RZ-FE engines



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Fig. Fig. 4: Exploded view thermostat and housing on the 5VZ-FE engine

  1. Unbolt the housing, then remove the water inlet with the hose attached. If there is not enough room to pull both housing and hose out, you may want to disconnect the hose first. On 3F-E engines, remove the clamp bolt for the ISC water bypass pipe. Make certain to remove the gasket with the water inlet. Some of it will probably stick to the housing and require scraping.
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Fig. Fig. 5: An extension is helpful for reaching the housing retainers



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Fig. Fig. 6: You may need to maneuver the housing through other hoses in the way

  1. Remove the thermostat.
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Fig. Fig. 7: Lift the thermostat and gasket from the inlet

To install:
  1. When installing a new thermostat always use a new gasket. Be sure that the thermostat is positioned with the spring down or into the housing. On 3VZ-E engines, the jiggle valve (looks like a small rivet in the edge of the thermostat) must be at the top or 12 o'clock position.
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Fig. Fig. 8: If used, the thermostat must be installed with the jiggle valve at the top

  1. Install the water inlet. Install the bolts finger-tight until the inlet is positioned exactly. Tighten the bolts to 10-14 ft. lbs. (13-19 Nm). Overtightening will break the ear off the housing and spoil your afternoon-don't do it.
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  3. Install the hoses and wire connectors removed for access. Make certain the coolant hoses are not kinked or twisted after installation. Do not overtighten the hose clamps.
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  5. Fill the cooling system with coolant.
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  7. Start the engine and check for leaks. Top off any fluid levels.
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