1. Noise start - Exhaust downpipe broke just below the mounting flange to the exhaust manifold. The pipe was repaired by welding. The rapping noise at start up began about three weeks later. It may or may not be related to the exhaust repair.

2. Changes before the noise started: Other than the exhaust work three weeks earlier, none.

3. Nothing special done to get car running well other than replacing filters, adjusting valve lash, dressing and setting points, replacing dist cap and rotor, replacing plugs, replacing choke cable sheaths, cleaning carbs inside and out . . .

4. Haven't tried pulling plugs and cold cranking. Is this a pressure test?

5. Have tried pulling plug wires -- besides getting shocked and the engine stumbling a little, nothing special changed.

6. Have not tried running with any of the plugs removed.

7. Rag at tailpipe sounds like it might help identify an exhaust leak location - thanks.

Free time yesterday ended up involving a carb swap on one of the other cars in the house. I'll try to get back to the 122 today.

Thanks for all the suggestions.

Joe M in WV

The other car?