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Please see photos of exhaust leak residue.

I will be replacing the manifold/block and exhaust pipe gaskets. I have purchased an intake/exhaust manifold joint gasket.

Should I use an exhaust manifold gasket sealer?

Also, there is residue around the exhaust deflector shaft. How can I resolve that? Some kind of bushing? New shaft?

I believe that much of the residue is from the previously faulty automatic choke. The plugs look much better now and the tail pipe moisture is not sooty.

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Did you put a straight edge on those surfaces? I'm guessing the they are no longer flat? Maybe those two surfaces should be machined? Manifolds are something I haven't played with on my car, at least not yet!

I worry that machining the mating surface between the intake and exhaust manifolds may increase the gap too much.

If it was me, I would use the gasket you bought and put exhaust gasket sealer on both sides. The sealer sets somewhat quickly.

I don't recall ever seeing a gasket there on any of my 1951-1954 Packards (that doesn't mean there wasn't one!) but all the soot is a sign of a tuning or carburetor problem. Whether leaking or not, it should not be putting all that out.

The parts book doesn't indicate a gasket, but I'm sure it wouldn't be an issue to put one. Other than to Kevin's point that machine would increase the gap, putting a gasket would reduce the gap. Maybe machine the surfaces and then use a gasket that will fill the gap?

Which cars had the heat shield (9.1115) for the carburetor? Seems like a good idea, but my 53 Cavalier doesn't have one.




I agree with Don, very sooty, it must have been running quite rich. Maybe just not enough run time to get things set due to chasing other issues. Time for an Italian tune up!

On another note, it's been -5 F here and I've been getting my car from storage so I could work on the rear fenders. It sure runs well, must be the cold air induction. I think I'm going to have to rework the gaskets in my heater controls, they're letting too much fresh air through when they shouldn't be. I replaced and adjusted them last summer, but I think the replacement gaskets are too stiff, which would be even worse in the cold weather.

I've never seen a heat shield on a 1951-1954 other than the one over the fuel pump which all had.

As for the gasket, I'm reasonably sure that none had it as there was no need what with the somewhat loose bushings needed for the heat riser shaft so really no point. These bushings must be relatively loose to allow for expansion in order to maintain the free motion of the shaft so there will always be some leakage. Now that the two have have been separated (something I never do unless I absolutely must), check both manifolds thoroughly and look for cracks. Maybe even have them Magnifluxed to be sure as sometimes cracks don't show up until very hot but Magnifluxing will find them. Also, I believe that the heat-riser hole in the manifold should have a tube running through it and these are often corroded away so be sure it's there and intact.

When it comes time to put the two manifolds back together, put the bolts in just snug enough so that the two aren't firmly locked together, then install the assembly onto the engine without gaskets. Tighten it to the block (I usually do so from the inside bolts to the outward ones, going side to side), then with it tight, tighten the bolts holding the two together. You'll probably be able to easily reach only the outer two but that's okay, just do your best on the one toward the engine. Once tight, remove it from the engine again, tightening the all three bolts to the proper torque, then lay a straight edge across the surfaces where they mate to the block. You might get very lucky to find they are flat but more likely the surfaces will have to me milled and probably best to do so anyway.

Some of the replacement manifold gasket kits do include a "hot box" gasket.

I'm sure there was something in a later service letter as well about it.