Packard Forum Index » Post-War (1946-54)

Fred in Florida

The heat riser valve is in the exhaust manifold below the carburetor. The 4" or so shaft goes front to rear, one end has a thermostatic spring and the other a weight. If it does no turn freely, spray with a graphited oil or penetrating oil and try to rotate the weight with a small hammer, up and back. Free it little by little while keeping it oiled and it will hopefully free up. If the spring is missing, get one.

There is probable a good illustration in the 48-54 parts book

You learn something new every day when you read this board!
After reading this thread I went out to the garage and sure enough my 23 series / '49 has a heat riser. Of course the spring and screw are missing and the weighted end feels rusted in place. Guess this is one more thing I need to fix or remove.

Thanks for the information.
B.

Glad you found the problem, most things are pretty simple after all