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

the gas is bolling out of carb. radiator is not boiling over do I need to insulate the fuel line ? the gasket is in between the intake and the carb.

I suspect the heat riser valve in the exhaust manifold is stuck closed. Many posts have been made, search for them

You didn't mention the year but in addition to the thick phenolic insulator gasket some models have a heat shield between the carb and manifold. If yours is one of those models and the shield has disappeared over the years, with todays more volatile gasoline a missing shield could also contribute to the issue.

Packard introduced changes to overcome this problem in 1930 see the attached letters to their dealers downloaded from this site

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I will go one step further, not only is Fred 100% correct, but I would advise ripping the damn thing out unless you drive your Packard in Alaska in the winter. The useless heat riser has caused more grief to Packard owners than is necessary....there is a whole trail of (unnecessary) frustration due to this flap.
Rip it out and put a couple stainless bolts where the shaft was. Done. Fixed. Problem solved.

We've owned hundreds of collector cars and hundreds of daily drivers, all but a few of which had heat riser valves. The ones where it was not functioning we fixed and enjoyed half a million miles of driving over the past 55 years. There is a reason that engineers since the '30's have designed them into virtually all automobiles and trucks.

If I take a collector car out for a drive in the fall/winter the driveability is just as good as summer and that's because of the heat riser valve. Carburetor icing and resultant complete loss of power is a very dangerous condition.

There is a simple fix for your problem which I'm sure you'll find and correct. Good luck

When I bought the '56 Carib it needed a new exhaust system and in so doing, I eliminated the heat riser valve. I do use the car in late Fall and early Spring and even occasionally in the Winter - and I do regret eliminating the heat riser.

OK, OK, I was in a bad mood. And yes, I was one of those frustrated somebody's that had a stuck heat riser flap. OK, rebuild yours, keep a watchful eye on it - let the engineers win this time.

Does my 22nd series car have this heat riser valve ? I am having problems with my rebuilt carb. thanks.

Yes, all Packards, except for maybe some of the early years have them. There are there to warm up the carb when the engine is cold, especially in cold weather. The problem is if the valve gets stuck, then the heat from a hot engine is then baking the carb. This valve is also the same function as other heatriser systems on other carb equipped cars.