Genuine Honda Odyssey Thermostat

Honda Odyssey Thermostat Parts Questions & Answers

• Thermostat Assembly
  19301-P8F-A11
  Q: How Do I Check and Replace a Thermostat?

  A: Before assuming the thermostat is to blame for a cooling system problem, check the coolant level, drivebelt tension, and temperature gauge operation. These models use the coolant temperature sensor(ECT) to read coolant temperature for the temperature gauge. If the engine seems to be taking a long time to warm up, based on heater output or temperature gauge operation, the thermostat is probably stuck open. Replace the thermostat with a new one. If the engine runs hot, use your hand to check the temperature of the lower radiator hose. If the hose isn't hot, but the engine is, the thermostat is probably stuck closed, preventing the coolant inside the engine from escaping to the radiator. Replace the thermostat. If the lower radiator hose is hot, it means that the coolant is flowing and the thermostat is open. Consult the Troubleshooting Guide for cooling system diagnosis.Disconnect the cable from the negative battery terminal. Drain the cooling system. If the coolant is relatively new or in good condition, save it and reuse it. Remove the battery. Follow the lower radiator hose to the engine to locate the thermostat housing cover. Use pliers to squeeze the coolant hose clamp and slide the clamp away from the thermostat housing. Loosen the hose clamp, then detach the hose from the fitting. If it's stuck, grasp it near the end with adjustable pliers and twist it to break the seal, then pull it off. If the hose is old or deteriorated, cut it off and install a new one. If the outer surface of the large fitting that mates with the hose is deteriorated, it may be damaged further by hose removal. If it is, the thermostat housing cover will have to be replaced. Remove the thermostat cover bolts and detach the housing cover. If the cover is stuck, tap it with a soft-face hammer to jar it loose. Be prepared for some coolant to spill as the gasket seal is broken. Note how it's installed - with the jiggle pin up - then remove the thermostat. Remove all traces of old gasket material and/or sealant from the housing and cover. Install a new rubber seal over the thermostat. Make sure the seal is aligned correctly with the rubber tang located directly above the jiggle pin. Install the new thermostat in the housing without using sealant. Make sure the jiggle pin is at the top and the spring end is directed into the engine. Install the housing cover and bolts. Tighten the bolts. Reattach the hose and tighten the hose clamp securely. Install all components that were removed for access. Refill the cooling system. Reconnect the battery. Start the engine and allow it to reach normal operating temperature, then check for leaks and proper thermostat operation.