Accelerator Pump Dia 32/36

OVERVIEW

When your air-cooled VW starts to stumble or hesitate during acceleration, the culprit is often a worn-out accelerator pump diaphragm. This EMPI Accelerator Pump Diaphragm is specifically engineered for the 32/36 Progressive carburetor, a staple for enthusiasts looking to balance fuel economy with increased performance. As a master specialist at Appletree Auto, I cannot emphasize enough how critical this small component is to your engine''s drivability. It is responsible for delivering that immediate "squirt" of fuel the moment you crack the throttle, compensating for the sudden rush of air and preventing the dreaded "flat spot" that can make pulling away from a stoplight a frustrating experience. This high-quality replacement ensures that your Weber, EMPI, or Holley-style progressive carburetor maintains a crisp, linear throttle response across the entire RPM range.

Constructed from modern, ethanol-resistant materials, this diaphragm is designed to withstand the harsh chemical properties of today''s pump gas, which frequently causes older rubber compounds to stiffen, crack, or delaminate. At Appletree Auto, we know that reliability is just as important as performance, which is why we recommend this EMPI 43-5726-0 unit for any 32/36 rebuild. Whether you are running a 1600cc dual-port in a weekend cruiser or a 1914cc stroker in a rugged Baja Bug, a fresh accelerator pump diaphragm is the cheapest insurance you can buy against poor off-the-line performance. Replacing this part is a straightforward process that restores the hydraulic seal within the pump housing, ensuring that every millimeter of throttle linkage movement translates into instantaneous fuel delivery and smooth power.

FITMENT

This accelerator pump diaphragm is designed for use with Progressive 32/36 series carburetors commonly found on the following air-cooled Volkswagen applications (when equipped with a progressive carb conversion kit):

• Volkswagen Type 1 Beetle: 1954 through 1977 (1600cc Dual Port conversions)
• Volkswagen Type 2 Bus / Transporter: 1955 through 1971 (1600cc engines)
• Volkswagen Type 3 (Fastback, Squareback, Notchback): 1961 through 1973
• Volkswagen Karmann Ghia: 1956 through 1974
• Volkswagen Thing (Type 181): 1973 through 1974
• Compatible Carburetor Models: Weber 32/36 DGV, DGAV, DGEV, and EMPI 32/36 Progressive clones

SPECS

• Brand: EMPI
• Part Number: 43-5726-0
• Material: High-grade Nitrile reinforced rubber (Ethanol resistant)
• Center Plate: Integrated steel reinforcement plate for lever contact
• Shape: Square pattern with 4-hole mounting flange
• Compatibility: Fits most 32/36 DGV series downdraft carburetors
• Application: Accelerator pump circuit fuel delivery
• Weight: 0.1 lbs (Shipping weight)

PRO TIPS

1. Check Your Spring Tension and Lever Alignment

When replacing the diaphragm, don''t just swap the rubber and call it a day. Always inspect the internal return spring and the external pump lever. If the spring has lost its tension, the diaphragm won''t return to its neutral position fast enough for the next throttle snap. Additionally, ensure the lever that pushes the diaphragm is clean and moves freely. A small dab of high-temperature grease on the contact point where the lever hits the diaphragm''s metal center button will significantly reduce friction and extend the life of the new part.

2. The "Squirt" Test Before Final Assembly

Before you bolt the carburetor back onto the intake manifold, perform a manual bench test. Fill the fuel bowl with a small amount of clean gasoline or carburetor cleaner. Manually actuate the throttle linkage and watch the accelerator pump discharge nozzle (the "shooter"). You should see a strong, consistent stream of fuel immediately upon movement. If the stream is weak or delayed, you may have a clog in the discharge nozzle or a check valve issue elsewhere in the pump circuit, even with a brand-new diaphragm installed.

3. Beware of Vacuum Leaks During Installation

The 32/36 progressive carburetor relies on a precise seal at the pump housing. When you are tightening the four screws on the pump cover, do so in a "criss-cross" pattern to ensure even pressure across the face of the diaphragm. Over-tightening one side first can pinch the rubber or warp the pot-metal housing, leading to a fuel leak or an air leak. Ensure the mating surfaces are perfectly clean and free of old gasket material or debris to guarantee a leak-free seal that will last for years of service.