Question about Nissan Sentra

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I have a 1990 Nissan Sentra that isn't blowing heat out properly so I was going to change the Thermostat out. I can't find the stupid thing. The top radiator hose on the passenger side goes straight to the motor and really should be right there. No thermostat. The bottom radiator hose on the drivers side goes up and around the back side of the engine. I can't see where this thing goes. Please help. Thanks

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Thank you for contacting

Generally in this type of case the cooling system is either air bound, meaning there is air trapped inside and not allowing proper fluid flow of you have hydrocarbons escaping in to the coolant system through head gasket, make sure the system is bled properly and take it to a shop to see if there are hydrocarbons in the system, a dead giveaway is a lot of pressure in the system, check the upper coolant hose after it has been running for a bit, if the hose is rock hard and you cannot squeeze it easily you have too much pressure, make sure the radiator is full and last but not least the water pump may not be circulating the coolant efficiently.

However the 1990 Nissan is equipped with a spring-loaded thermostat that is designed to open when the engine overheats or starts to overheat.

First you have to open the hood to access the coolant system. Locate the upper radiator hose, and trace it to the engine.Unclamp the radiator hose from the thermostat housing by unscrewing the hose clamp with a flathead screwdriver. Pull the hose off the thermostat housing inlet pipe.

Now unbolt the housing cover from the housing with a socket wrench. Pull the cover off to expose the thermostat.Pull the thermostat out of the housing. Place the new thermostat in the housing. Position the end of the spring to go in first.After that scrape the gasket material off the surfaces of the housing with a razor scraper.You need to be sure that all the black gasket material is removed before putting the housing back together. When you are finished lay the new gasket around the housing. Line up the bolt holes to the studs on the housing.Now you have to position the housing cover over the thermostat housing. Tighten the bolts with a socket wrench.Slide the radiator hose onto the pipe. Secure the hose clamp over the hose and the pipe. Tighten the hose clamp with a flathead screwdriver. Now twist the radiator cap counterclockwise to expose the coolant level. Pour pre-mixed coolant into the radiator until the level is full.Start the car with the radiator cap off. Allow the Nissan to warm up. When the vehicle is warm, the coolant level will drop. Fill with coolant, and secure the cap onto the radiator. Ckeck the coolant system for leaks.

Please get back to us if you have any further query.

Have a nice day.

Posted on Nov 12, 2010


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