1. Identify the Leak:
* Locate the hose: Find the hose running between the thermostat housing and the intake manifold. It's usually a relatively short, thick hose.
* Inspect the hose: Look for cracks, holes, bulges, or signs of significant wear and tear. Check the hose clamps at both ends – are they tight and properly seated? Sometimes, a seemingly minor leak is actually caused by a loose clamp.
* Check the connections: Inspect the thermostat housing and intake manifold connections for cracks or damage. A leak might originate at the connection, not the hose itself.
2. Repair Options (in order of least to most involved):
* Tighten hose clamps: This is the easiest fix. Use pliers or a clamp tightening tool to tighten the clamps on both ends of the hose. If the clamps are damaged, replace them. This often solves the problem.
* Replace the hose clamp(s): If the clamps are rusty, damaged, or broken, replace them with new ones of the correct size. You can find these at most auto parts stores.
* Repair a small hole or crack (not recommended): For a very tiny hole or crack, you *might* be able to use a hose repair kit with a rubber patch and adhesive. However, this is a temporary fix and not reliable long-term. It's generally better to replace the hose.
* Replace the bypass hose: This is the most reliable solution. You'll need a new hose of the correct size and type. Auto parts stores can help you find the correct replacement.
3. Replacing the Bypass Hose (if necessary):
This requires basic mechanical skills and tools. Always let the engine cool completely before working on any coolant system components.
* Gather supplies: You'll need the new hose, new hose clamps (if needed), a flathead screwdriver (possibly), pliers or a clamp tightening tool, rags, and possibly a coolant recovery container (to catch any spilled coolant).
* Drain some coolant: Slightly drain the radiator to reduce the amount of coolant that spills out when you disconnect the hose.
* Disconnect the hose: Carefully loosen and remove the hose clamps. Gently pull the hose off the connections. Be prepared for some coolant spillage.
* Install the new hose: Slide the new hose onto the connections. Make sure it's seated properly.
* Secure the hose: Attach and tighten the new hose clamps securely.
* Refill the coolant: Add coolant to the radiator and overflow reservoir as needed.
* Check for leaks: Start the engine and let it run for a while. Carefully check for any leaks around the new hose and connections. Let the engine cool completely before checking again.
Important Considerations:
* Coolant Type: Use the correct type of coolant for your Cavalier. Check your owner's manual. Mixing different types of coolant can cause problems.
* Safety: Coolant is toxic. Wear gloves and eye protection when working with it.
* Professional Help: If you're not comfortable performing this repair yourself, take your Cavalier to a qualified mechanic.
By following these steps, you should be able to successfully repair your 2000 Chevy Cavalier's bypass hose leak. Remember to always prioritize safety and use the correct tools and parts.
