2002 BMW 330i still running hot after replacing thermostat & housing, fan,fan clutch, auxiliary fan and flushing radiator
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2002 BMW 330i Question: BMW 330i running hot
Answer #1backyard tech December 03, 2009, 20:28Master
You need to have it checked with a gas analyzer for a blown head gasket.
patrick mannion from Greg Solow's Engine Room, December 04, 2009, 09:22Master
Some BMW's experienced water pump impeller failure. The plastic impellers spun on the shaft or failed (a problem also experienced by some Jaguar V8 and VW cars), not sure if your car falls into this catagory but keep it in mind. perhaps call a BMW specialty shop in your area tell them "you heard some BMW's experienced water pump impeller failure had they seen it on your make/model/year?".
See that the radiator is allowing good circulation feel for cold spots with the engine running (use caution).
The most accurate way to test for a blown head gasket on a gasoline engine is to test for the presence of carbon monoxide in the cooling system. Snap-On, Matco (part # CO 2000), and Napa sell a tool to check to carry out this test. Another link to a supplier of this tool is http://www.etoolcart.com/combustion-leak-detector-lis75500.aspx. Carbon Monoxide is only present if there is a blown head gasket or cracked cylinder head. http://www.arrowheadradiator.com/head_gasket_or_combustion_leak_test.htm I think the Napa part number 700-1006. http://www.blockchek.com/instructions.htm . Signs of a blown head gasket are coolant loss (frequently have to top up the coolant level of the engine without seeing an obvious leak), experiencing over heating or rough engine running or the presence of white sweet smelling steam from the exhaust.