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I'm in the process of assembling the 47 356 engine.
I ordered new gaskets for the valve job. The manifold gaskets that I received were "different" than the old ones. The new manifold gaskets were the "individual"
round 4 intake and 2 exhaust gaskets and 3 double exhaust gaskets. The old ones that I took off were the three
flat types that are between the manifold and block.
They were not working that well because several of the
exhaust areas were "burnt" through.
Are the new ones that I ordered the correct ones?
I think that they would do a better job than the flat ones.

Also, when reinstalling the manifolds, do they go back on as a unit, of do they go on "loosened" in the exhaust hot box area, mount them as a unit, tighten the manifold assembly to the block, then tighten the hot box bolts..

Just looking at the manifold assembly on the bench, it looks like the mounting surfaces are a bit off.

I looked in my shop manual and it isn't much help in that area.

Lauren R Lampi
Grand Rapids, Minnesota
47 Custom Supper Clipper

Remember, the manifolds must move a bit back and forth as they expand differently than the engine block, so torque of the manifold bolts is important to permit that small movement. There are quite a few different types of gaskets available but the best are the OEM type some of which were steel sandwiches with lips that inserted into the ports. Find them if you can though myself and others have used the replacement type of composition gaskets without problems.

If you assemble the heat box first you have a good chance that the manifolds will not align properly with the ports on the block. Have the manifolds checked for flatness and if OK, install them first and then fit the heat box.

Thanks for the reply.
I must have gotten the OM type of gaskets because they have the lip that goes into the port and the metal and
asbestos sandwich that fit along the block.

I am not completely clear about the recommended sequence for installing the manifolds.
Is it recommended that the intake and exhaust be installed separately. (Exhaust first and intake second)
Or are they installed together, with the three bolts on the heat box loose so there would be a bit of play between the two manifolds. Then start to snug up the manifold to block fasteners and the heat box bolts.

Before I bolted the two manifolds together at the heat box,
then installed the everything as a single unit.

Lauren R Lampi
Grand Rapids, MN

I took another look at the manifold assembly that I have on the bench. Took out the three bolts that hold the assembly together at the heat box. There is a little clearance in the bolt hole that holds the two together.
Also found that there was NOT a gasket for the two manifold pieces. I have a new hot box gasket so that will be installed on assembly.
after everything in cleaned up and painted, I will assemble the manifolds but leave the hot box bolts a little loose.
After I attach the manifolds to the block, I will gradually
tighten all bolts to align the manifolds.
One step at a time.
It will be good to get the 47 back on the road.
Hot here in Northern Minnesota.........80's.

Will start to cool down next week.

Lauren R Lampi
Grand Rapids, Mn

Packard did not use a gasket between the intake and exhaust manifolds for the 356 engine. They did use one for the 120's and 8 cylinder Clippers.

I was not aware that the 356 engine did NOT have a gasket between the intake and exhaust manifolds at the "Hot Box" area connection. The suppliers sell them and that is why I purchased one to use on my repairs..
So don't use the gasket at the hot box.
The gasket that I got looks like it is made for that area.

Lauren R Lampi
Grand Rapids,MN

Yes but.....there was no gasket in that area when the machining was all nice and new and flat and undisturbed. That is no longer the case, which is a good reason to use the gasket. That is pretty well standard practice unless one has some extra nice manifolds.

Thank you for the reply and information on hot spot gaskets.
I was looking at the Max Merritt on line catalog this AM.
It listed the hot spot gaskets and showed a photo of the gasket. This is the one that was sent for 356. I will check the fit and alignment of the manifolds to see if I need to use it for the installation.

Lauren R Lampi,
Grand Rapids, MN

How did you install them? in pieces or as a unit? I have this job coming up myself...
Thanks