DIY Network

1938 Packard: Carburetor Installation, Adjusting Idle Richness From "Classic Car Restoration" episode DCR-404

In this episode of Classic Car Restoration, host Mark Lambert addresses the fuel system on the 1938 Packard Club Coupe. The fuel system is often the most misdiagnosed and misunderstood system on any car. In reality, if taken component by component, it’s quite simple. In this fourth segment of episode 404, Lambert installs and adjusts his rebuilt carburetor and also adjusts the idle.

Note: This is a summary of steps included in the automotive restoration procedures shown in this episode of Classic Car Restoration. These are general guidelines for restoration procedures on this particular make and model of vehicle, and for the level of restoration selected for this project. There may be variations in procedures depending model, condition of vehicle, level of restoration undertaken and the types of replacement parts or upgrade kits selected. Always follow proper safety precautions, and read and follow manufacturer's guidelines, diagrams and safety notices that come with any replacement parts or kit that you select.

advertisement

Carburetor Installation

Before you start, take a look at our base gasket. That’s our old one, this is our new one (figure A). If we had to reuse this base gasket it would be all right but we’d have to get the position perfect or we’d risk a leak. Since we had the new one, we replaced it. One more thing...this is the base insulator (figure B). This is where the intake manifold ends. The insulator is there because you’ve got to have something to hold the heat down in the engine. If your heat goes up too high in the carburetor, your fuel will boil. Finally, always lube the threads before you start. Then, the nuts will start and you won’t get cross-threaded. Now, center the carburetor (figure C).

Figure A

Figure B

Figure C

Materials:

Wrench
Lock washers
Mixture screws

• Center the carburetor and add a drop of lubricant to the studs. Be sure to use lock washers on the studs and tighten the nuts, first by hand. Then use a wrench in a cross pattern from each stud to tighten it evenly, about 18 pounds of torque.

• Put your nuts on. Pick up the threads by hand. As you tighten these down with your wrench, work in a cross pattern. This is the little stuff that counts so much. The details are what makes the difference between a car that just runs and a car that is really nice and responsive.

• If you’re going to have your manifold open for any amount of time always cover your bores going down the manifold. You don’t want any debris dropping down there.
  

  Figure D

• Hook your throttle linkage and choke linkage up. Both of these are adjustable. We liked our choke adjustment, so we left it alone. Secure both linkages with cotter pins (figure D).

• Check your linkage. This is critical and a step a lot of people miss. You want it for two reasons. You don’t want this sticking when you floorboard it. If your butterflies are all the way open at full throttle, this is what you want.

• Fill your carburetor with fuel by delivering from your fuel pump. Out of gear, spin the engine a few times to deliver the fuel and fill the carburetor and check your accelerator pumps.
  

  Figure E

• The next thing you want to do is to confirm that your accelerator pumps are working. We stroked ours a couple of times (Figure E) and gave it two blasts of accelerator pump gasoline in the bore so that it was staying down at the bottom of the manifold. This should start first cylinder up when the switch is turned on.
  

  Figure F

• Set your mixture screws (Figure F).
  
  
  

  RESOURCES :
  
  
  Resources and Special Thanks for Classic Car Restoration 400 series
  
  
  The Packard Club
  Columbus, Ohio
  (National & regional clubs, car shows & judging, magazine, resources, etc.)
  The Cormorant magazine
  The Packard Club
  www.packardclub.org
  
  Packards International Motor Car Club
  (National owner's club, judging rules, magazine, newsletter and other resources)
  Santa Ana, CA
  Packardsinternational.com
  
  Packards of Chicagoland
  (Regional affiliate of The Packard Club)
  Elmhurst, IL
  Packards of Chicagoland
  
  America's Packard Museum
  Dayton, Ohio
  www.americaspackardmuseum.org
  
  The National Packard Museum
  Warren, OH (the birthplace of the Packard)
  www.warren.org
  
  The Packard Motor Car Foundation
  (Foundation for preserving the Packard marque) Restoring the Packard Proving Grounds and other Packard activities.
  www.packardmotorfdn.org
  
  Motorbooks International
  www.motorbooks.com
  
  Automobile Inspections LLC
  (Nationwide automobile appraisal & inspection services, including classic cars)
  Hartford, CT
  www.automobileinspections.com
  
  Classic Auto Appraisals (Evaluation of Classics, Street Rods, Antiques, Competition Cars, Exotics, Commercial Vehicles and Hand Crafted Vehicles).
  www.autoappraisals.com

  ALSO IN THIS EPISODE:
  	1938 Packard: Safety, Fuel Additives, Fuel System
  	1938 Packard: Fuel Pump Pressure and Volume Test, Removing Carburetor
  	1938 Packard: Clean and Rebuild Carburetor
  	1938 Packard: Carburetor Installation, Adjusting Idle Richness