Packard Forum Index » V-8 (1955-56)

I bought a rebuild kit for my 400 (56 Super engine). Besides "read the manuals" and "be careful", anything to keep in mind?

I have the Service manual, the specific carb manual for 55, and a couple instruction sheets from the carb manufacturer (Chicago carb).

Thanks everyone.

If relying on the manual, might check thru the bulletins and look at the changes between the carbs. There were some differences in settings between 55 and 56 carbs too.

Good idea. I have been reading thru the bulletins / index.

Pulled the carb off today. Fingers crossed.

What is the small metal tube attached right at the base? Not the large port which appears to be manifold vacuum.

Without seeing it, hard to say but the tube for the vacuum advance comes off the carb so it might be that item. About 1/8 or maybe 3/16 OD steel tube heading toward the dist at the rear?? There is also a 1/4 tube for the wipers coming off the carb. That heads over toward the right head and then back but that one may also be coming from the same fitting where the power brake check valve is located.

be patient when dealing with the carb. Make sure you have the appropriate size screw drivers to remove the fasteners.

being clean will be your friend. Carb cleaner will only go so far. If you can sink it into a bath to soak or an ultrasonic cleaner would be best.

The jets are brass, again make sure you have the appropriate sized driver to get them out.

Getting yours apart may be fairly simple and straight forward, but depending on how the carb was cared for the past 65 or so years there could be some varnish keeping everything stuck together.

Thanks everyone for the replies so far. So 2 months later finally getting around to it (we moved my dad about 1000 miles to live near me in the meantime).

A couple questions...

- Is the choke piston supposed to have rings on it?

- There is some chalky buildup on the inside. Is this normal?

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The buildup is probably dried up fuel.

No, the choke piston is not fitted with rings.

That ring detail on the piston is referred to as a labyrinth seal. In that application the groove allows the pressure to equalize around the circumference of the piston and center the piston in the bore. At constant operating clearance, more grooves result in less leakage. So, the grooves are one means to have smooth low operating force pistons while maintaining low leakage flow.

dp