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

Another possible source of a vacuum leak is the upper diaphragm of the double acting fuel/vacuum pump.

Brian

I agree with all those possible sources of vacuum leak, but even if they all leak, I doubt that would make the car unstartable when hot to the extent that has been described. If indeed the problem is due to vacuum, it must be a very large leak. I'd think more in terms of a cracked manifold or something much more significant. And when I got it started I'd put a vacuum gauge on it to see what the running manifold vacuum is.

I agree it takes a substantial vacuum leak to make the engine hard to start. However, I have had a worn engine that smaller leaks caused it problems in running smooth and starting. After rebuild, the engine started quite well cold or hot. But, the engine ran a little rough. I found a vacuum leak in the antenna. The vacuum line had gotten hard and split at the connection to the antenna. Replaced the line and the engine smoothed out.

So, If you haven't done so by now, check all of the items listed above. These items can accumulate and cause the kind of problem you seem to be having.

Good luck.

tightened up bolts to carb and also all screws on the carb. a/p squirts gas when pedal depressed.ran car in garage till warm and then killed it and tried to restart.good news is that it started right up. will test drive this weekend weather cooperating. vacuum at idle is 20. will keep you posted.thanks for the ideas

Good news, 20 inches of vacuum at idle is just excellent, especially if the reading is very steady.

very steady, goes upward of 26-28 when revved up a little