Re: 1947 Clipper 6 cyl distributor adjustment ?

Posted by Daniel Leininger On 2008/10/19 18:31:01

Dave,

Have you checked the heat riser? (aka. heat control valve, manifold valve)? This devise is designed to preheat intake air on startup, thus giving better idling to a cold engine. On warming-up it closes. If it doesn't it can contribute to overheating in hot weather and 'reduced fuel efficiency' (if I can use such a phrase on a 'Packard' website)

I just learned this important quick 'fix' for my rough-running at start-up problems.

You may know all of this, BUT I didn't until an hour ago. The heat control valve is in the exhaust manifold under the carburetor. Mine has been rusted 3/4 open for 1 to 20 years (I have only had the Clipper 1 year, I don't know the rest).

I had to tap one end of the valve shaft with a small ball pene hammer until it moved a bit. Then I tapped the other end (where the bi-metal spring is). Begin lightly then more vigorously until the shaft can be tapped from side to side. Maybe yours is not that rusty. Mine was!!! Eventually, I could tap it backward and forward, but it would not turn by hand.

I started using a spray can of carb cleaner (it actually said 'good for heat risers' on the can). Finally, I lightly tapped the counterweight in the rear end of the shaft and the shaft turned slightly. More taps, more spray, more hand turns and within 15 minutes of start time and walking back and forth for tools (good exercise without fitness Center prices), the heat riser would set itself and the manifold spring on the front end would control the shaft as designed.

Love them Packards. They are made to work.

Test drive Results. Heat riser is open on start-up when engine is cool. Heat riser closes on engine warmup.

Perhaps your heat riser is stuck open or mostly open like mine was. This can also contribute to overheating as exhaust air

Good Luck
DanL