Serial Number and Intake Manifold

dr01a1940

Hi everyone: My son-in-law is in the process of ending up with a Hudson Super Six convertible that has belonged to his grandfather since 1979. Unfortunately, his grandfather is now 90 years old and can't help at all with providing any info about the car. I'm more a street rod guy from the 1960's, but am helping him get it going after being in storage for about 5 years or so. It's a cool car and I'm having a ball thus far. The car is titled as a 1947, but the serial number from the title and door post being 3173678 falls into the range that online sources cite as a 1946 Series 51. My first question then, "Is the car really a 1947, or could it be a 1946 that has somehow been titled as a 1947 at some point?" The engine has a casting number of 304539 with head markings of 308 and Power Dome 309121. The block is stamped at the right front as 202797 which online sources would identify as a "late?" 1952 model year engine/SN. We are currently replacing all the electrical tune up parts in hopes of getting it running soon. My question with regard to the engine is that there seems to be a hole in the intake manifold casting just below the carb and facing the fender where perhaps a plug of some type was and should be. It backfired some flame out of this hole when we were initially cranking it. I plan to just use some metal tape over it temporarily, but "Can someone shed some light on this hole/missing plug?" I'm new to this forum and look forward to everyone's expertise as we get this classic back on the road! By the way, the car has been converted to 12V, negative ground in the past.

Per

The source of vacuum for the wiper motor is connected to the intake manifold.  If the fuel pump doesn't have a vacuum section, the small rubber tube from the wiper motor should go to a fitting screwed into the manifold.  If the fuel pump does have a vacuum section, the rubber tube from the wiper motor goes to the vacuum part of the fuel pump. and metal tubing goes from the vacuum part of the fuel pump to a fitting screwed into the manifold. 

If the wiper motor has been replaced with an electric motor, this hole could be where the wiper system was attached.  

Sometimes the small metal tube for the vacuum advance is connected to the carburetor, but sometimes it is connected to the manifold.  It may be disconnected.

If both of these systems are connected, then you should just plug the hole.

Per

dr01a1940

Thanks for the info. We will be traveling to where the car is located tomorrow and I will check it out and take some pictures as well.