https://clublexus.com/how-tos is the leading Lexus IS, RX, ES, and GS resource for technical DIY guides. Replacing the thermostat in your Lexus RX is an important maintenance item that ensures your engine runs properly and the components don’t overheat. For the full step-by-step article, please visit https://www.clublexus.com/how-tos/a/lexus-rx-how-to-replace-thermostat-366260
An overheating engine can be one of the most damaging conditions a car will experience. When the engine runs too hot, the seals and gaskets around key components can warp and fail. A faulty thermostat can force the engine to overheat by preventing coolant from flowing through the radiator. Fixing and replacing a faulty one is easy and will save a considerable amount of time and money compared to leaving the job to a mechanic.
This moderately difficult job takes two to three hours and costs around $25 to complete, compared to the professional repair cost of $120 to $170.
This job requires a jack and jack stands, a torque wrench, a 5 millimeter bi-hexagon wrench, a socket wrench, a ratchet, a 13 inch extension, an 8 inch extension, a cheater bar, a bucket or catch pan, a flat head screwdriver, coolant, and a new thermostat.
Step One – Remove the serpentine belt
In order to access the thermostat on the Lexus RX, you must remove the serpentine belt first.
Jack up the front end, remove the passenger side front wheel, then remove the panels from the fender well. Loosen the belt tensioner with a socket wrench, and place a 5 millimeter bi-hexagon wrench through the bottom hole. Pull the belt from the pulleys.
Step Two – Locate the thermostat
Most thermostats are located where the radiator hose goes into the engine, and the RX isn’t any different. Follow the upper radiator hose to the engine block, which connects to the engine’s water inlet. In that pipe is the thermostat. In order to remove the thermostat, that pipe will have to come out.
Step Three – Place bucket under where you’re working
Removing a thermostat or radiator hose will cause a lot of coolant to be spilled. Place a bucket underneath the connectors to minimize the mess.
Step Four – Remove the number two idler pulley
The idler pulley is located underneath the water inlet. You’ll need to remove this pulley in order to remove the water inlet, otherwise it’ll block access to the bolts securing the inlet. Wedge a screwdriver between the pulley and the engine or water inlet to keep the pulley from spinning. Unbolt it with a long socket wrench.
Step Five – Remove water inlet
The upper radiator hose will likely be strapped to the water inlet via a clamp. Take a flat head screwdriver and loosen the clamp. Once the clamp is loosened, pull the hose off the water inlet. This will reveal the two bolts holding the thermostat in place. Remove these bolts and pull off the water inlet to expose the thermostat.
Step Six – Remove thermostat bolts
Remove the thermostat and be sure to remove the gaskets as well. Clean the new gasket seats of the replacement thermostat while making sure no rubber crumbles off or gets dropped into the engine.
Step Seven – Replace the thermostat
Once the thermostat seat is cleaned, replace the new thermostat and gasket, securing it with the bolts originally removed.
Step Eight – Replace the hose, clamp, and fluid, and clean up
Once the thermostat has been replaced, re-install the water inlet. Slip the radiator hose back onto the inlet and secure the clamp as it was before you started. Once secure, take the fluid that spilled into the recovery bucket and add it back to the radiator. Be sure to mop up any spilled fluid as it can be deadly if accidentally ingested by animals.
Post time: Jun-10-2017