Leaking head gasket can spell doom for car

Q. I have 2000 Eldorado with 82,000 miles. I bought it new and have always kept up the service. About a month ago it overheated.

The heat indicator had always been steady in the middle. When the vehicle cooled, I checked the coolant level and it was down. I filled the reservoir and started the car and let it run.

It overheated again. There was nothing under the car, no water from the tail pipe, no sweet smell from the tail pipe, no steam from the engine. I changed the water pump, radiator, reservoir — with no help.

The engine runs fine but I can’t drive two miles before it overheats and the coolant level goes down. Have you heard of this before? Where is the coolant going?

Is it a problem with the Northstar engine? Do I have to take it to a mechanic?

A. I definitely would take your car in and have it checked out. The coolant can only go one of a few places.

It can leak externally from the engine or a hose. It could leak from a heater core into the passenger compartment (causing a wet carpet). It could leak into the transmission fluid via the transmission cooler; the transmission fluid would be milky and overfull. Or the engine could be burning it.

It sounds like the engine might be burning it from your description. It is possible you have a bad head gasket, which can be a big problem on the Northstar engine.

The head bolts go into an aluminum block and many times it is impossible to remove the bolts without destroying the threads in the block. When this happens, the engine has to be removed for repair and sometimes has to be replaced.

Before you jump to any conclusions, I would have a professional determine exactly where the coolant is going so that you can make an informed decision.

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