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Toyota Repair/slow water leak


85 Toyota 4-runner manual trans, 4 cylinder. 300,000 miles

After an hour or so of driving the water level goes down and engine overheats.

Is this a main gasket or engine leak, or could it be the water pump? I replaced the water pump several years ago with a rebuilt.

The first thing is to inspect if there is a visible external leak, you may have to have the cooling system pressurized, if there is no external leak there is a good chance that it has a leaking head gasket, you can have it checked for this at most repair shops, they can do a chemical test to look for hydrocarbon emissions in the cooling system

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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