Details for Click & Clack.
Click & Clack Talk Cars “The Tappet Brothers’’ By Ray Magliozzi Mystery overheating May be due to cooling fan BY RAY MAGLIOZZI Dear Car Talk: After weeks of visits to two different mechanics, over $1,000 paid in repairs and three tows in two weeks, I am finally getting desperate enough to write to you guys! When the engine is at operating temperature, and you’re on the highway, you get plenty of airflow to cool then engine because you’re moving. That air that blows in through the front grill keeps the engine from overheating. I want to extend the life of But once you’re stopped at a my 2002 Buick Rendezvous. I inherited it after the engine had red light, the natural airflow stops, and you need an electric fan to been replaced (in 2007). blow air through the radiator. We found we needed to add So, check and see if the additional coolant about every six cooling fan is cycling on and off months, until a couple of months ago when the temperature gauge like it’s supposed to. If it’s not, maybe the radiator solved the suddenly went red. problem, and all you need is to We added coolant and fix the cooling fan. If the coolant our mechanic replaced the fan IS coming on and off, then the thermostat and flushed the news is far more serious. system. Days later, it happened Mostly likely, you needed a again, and the car died on me, radiator from the very beginning. But, but miraculously worked fine once it got back to the shop. I unfortunately, during one of those was told it had a “bubble in the four (or 14) times you overheated the heck out of the engine, you blew coolant line.” a head gasket or cracked the head. Two weeks later, it overheated Or worse, cracked the block. again, and a new mechanic So, start by figuring out if the replaced some parts for $700 -- he said the tubes might be cooling fan is working properly. If clogged in between the radiator it is, ask your mechanic to test for and engine. On the way home, it a blown head gasket or cracked overheated and died. So, back to head or block. We use a dye test, mechanic No. 1 for a new radiator or we test the radiator vapors for the presence of exhaust. If the AND another new thermostat. tests come back positive, and All seemed to finally be healed the rest of the car is still in good -- for a week. Then, my son drove shape, then it’s time for engine the car for 2 1/2 hours on the No. 3, Mrs. Martinez. highway, and when he came to a And this time, ask them for one stop at a red light, the temperature gauge went red again, then went of those punch cards, so when back to normal by itself once he you get to your 10th engine, you’ll get the 11th for free.” started driving again. It happened twice more on his way home. The car has been sitting unused for a week while we try to figure out what to do next. Any suggestions on how to repair the coolant problem? Kind regards. -- Mrs. Martinez *** Got a question about cars? Write to Ray in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email by visiting the Car Talk website at www.cartalk.com. *** Are you sitting down, Mrs. (c) 2018 by Ray Magliozzi and Martinez? If you’re incredibly Doug Berman lucky, and you’ve lived a good, Distributed by King Features clean life, you may just have a Syndicate, Inc. bad cooling fan.