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

Mine does have a heat shield, but it was not original to the car...was added by the previous owner to help prevent vapor lock (this must have been before he decided to add the electric fuel pump). At any rate, at my next opportunity to recreate the same conditions, I'll plan on immediately flooring the throttle upon starting the car to see if that works.

Re heat shields, the parts book will confirm by my memory says the 282, 288, 327, 359 and 356 engines all had heat shields around the fuel pump, but only the 356 had the second shield under the carburetor. But despite being non-authentic, adding a shield under the carburetor, as well as making sure an insulating block is installed, will not hurt and probably will help.

My own experience says that with a car in good condition, even when driving in stop-and-go July 4th parades at 100 degrees, electric fuel pumps should not be necessary as a replacement for the mechanical fuel pump though today's gasoline surely isn't helping any. Some folks use an electric just to prime the carburetor after long periods of non-use.

I'd still believe your problem is probably excessive fuel pressure, a leaking needle and seat or a bad carburetor float, or as has also been suggested, a clogged anti-percolator valve (or fuel bowl vent). On the WDO and perhaps the WDG series there is a diecast metal cover with the Carter trademark, held on with 2 fillister head screws. Beneath it are the adjustments for the anti-percolator valves, metering rods, and accelerator pump. Check this out, and don't forget a drop or two of oil on the shaft supports.

And don't forget to check the exhaust manifold heat riser valve.

I'm not familiar with the subject car as equipped, but a friend's 1950 Pontiac was fitted with a metal heat shield. In addition to reflecting/deflecting heat, that shield may have also worked like a heat sink, but everything has its limits.

I suggest the owner move carefully and checking for a flooded condition is a good first step. Then report back with findings.

I don't have a carb heat shield on my '47 with the 356 engine. It was removed before I bought the car. I have not had any vapour lock problems ever and a few trips have been made in 90 degree heat and also several parades.

Just checked the 22nd and 23rd series parts list. It only lists the carburetor heat shield for the 2206 chassis (the Customs)

Just to bring this issue to somewhat of a closure at this point, I did recreate the conditions over the weekend. I resorted to flooring the throttle on startup, and....surprise, surprise...it started. So, I do think the issue is fuel percolation/foaming during "hot soak." I believe the gas in the tank is still from April, which would probably be a winter grade gas around here (Michigan). It will be interesting to note if I continue to experience this phenomenon once I add some summer grade gas to it.

That's somewhat good news.

Please keep us posted here - as your experience could help fothers in the future.