Friday, January 18, 2008

Scary Carbon-Monoxide

One of the many unusual things about Corvairs is our method of keeping their passengers warm on cold days. Since we’re air-cooled, there’s no hot liquid available to run through a heater core like most other cars. GM designers copied VW’s method of circulating air (the same air that’s cooling the engine) over the hot heads and cylinders and then plumbing it into the passenger compartment. With an engine that has all its passages sealed properly, this is a safe condition. However, on a cold day when an exhaust gasket (packing) fails, the heater becomes the deadly deliverer of carbon monoxide to the passenger.

This happened to me last week. Ariel and her sister noticed a new, unpleasant smell in the car. They said it smelled like exhaust. Ariel’s dad took a look at my exhaust system and didn’t see or hear anything amiss. Remember that I have a very loud dual exhaust system, so trying to listen to something different is not very effective.

Regardless, he put a CO detector in the car, and the next day on their drive home from school the alarm went off. Ariel called her dad, and asked what to do. He told them to turn OFF the heater and roll the windows down and open the floor vents. That night he replaced my loud exhaust system with the much quieter stock one, and lo and behold he heard an exhaust leak inside my engine. After removing the sheetmetal shroud that covers the driver’s side exhaust, he felt a significant leak at the exhaust manifold to head junction.

I’m now off the road until new packings from the Corvair Ranch show up in the mail.