Master Carburetor Rebuild Kit, 40 & 45 DCOE Weber

OVERVIEW

When it comes to extracting maximum horsepower and crisp throttle response from your high-performance air-cooled engine, the Weber DCOE series remains the gold standard of side-draft carburetion. However, even the legendary DCOE can fall victim to the ravages of time, heat, and modern fuel additives. The EMPI Master Carburetor Rebuild Kit for 40 and 45 DCOE Weber carburetors is the definitive solution for the enthusiast who refuses to settle for a "good enough" tune-up. Unlike basic gasket sets, this master kit is engineered to provide a comprehensive overhaul, replacing the critical internal components that directly impact fuel atomization, idle stability, and wide-open throttle performance. Whether you are running a vintage road racer, a high-compression street Beetle, or a dual-carbureted Ghia, this kit ensures your fuel system can keep up with the demands of your right foot.

At Appletree Automotive, we know that modern ethanol-blended fuels are particularly aggressive on older rubber and fiber components, leading to brittle diaphragms and weeping gaskets. This Master Kit (EMPI Part Number 43-5808-0) includes high-quality, fuel-resistant materials designed to withstand the rigors of today''s pump gas. By replacing the needle and seat assembly, the accelerator pump diaphragm, and all essential O-rings and seals, you eliminate the vacuum leaks and fuel pressure inconsistencies that cause "flat spots" or stumbling during acceleration. Rebuilding your 40 or 45 DCOE with this kit isn''t just about maintenance; it''s about restoring the surgical precision that Weber carburetors are world-renowned for. Don''t let a tired carburetor bottleneck your engine''s potential when a professional-grade restoration is within reach.

FITMENT

• Weber Carburetors: 40 DCOE (All Series)
• Weber Carburetors: 45 DCOE (All Series)
• EMPI Carburetors: EPC 40 and EPC 45 Side-draft models
• VW Type 1: Beetle, Karmann Ghia (With side-draft manifold conversion)
• VW Type 2: Bus, Transporter, Single Cab (With side-draft manifold conversion)
• VW Type 3: Squareback, Fastback, Notchback (With side-draft manifold conversion)
• Custom Applications: Dune Buggies, Sand Rails, and Trikes utilizing 40/45 DCOE style carburetors

SPECS

• Part Number: 43-5808-0
• Kit Type: Master Overhaul Kit (Comprehensive)
• Needle and Seat: Precision-ground brass assembly with viton-tipped needle
• Diaphragms: Heavy-duty accelerator pump diaphragm for consistent fuel "shot"
• Gaskets: High-density fiber top cover gasket and base gaskets
• O-Rings: Solvent-resistant nitrile O-rings for mixture screws and jet holders
• Washers: Full set of fiber and aluminum sealing washers for fuel inlets and banjo bolts
• Fuel Filter: Internal fine-mesh fuel inlet screen included
• Compatibility: Suitable for both genuine Weber and EMPI EPC side-draft variants

PRO TIPS

1. Cleanliness is Next to Godliness

Before you even crack open the carburetor, ensure your workspace is clinical. A single grain of sand or a tiny piece of lint can clog an idle jet or prevent the needle and seat from sealing properly. We recommend a full teardown followed by an ultrasonic cleaning bath or a soak in high-quality carburetor cleaner. Once the body is clean, use compressed air to blow out every single passage, including the progression holes and the main well. If you can''t see light through a passage, it isn''t clean yet. Reassembling a carburetor with even microscopic debris will negate the benefits of the new components in this master kit.

2. Master the Float Level Adjustment

The most common mistake during a DCOE rebuild is ignoring the float level. The Master Kit includes a new needle and seat, which may have a different seating height than your old one. You must check the float height (usually measured with the gasket in place and the float tang just touching the needle ball without depressing the spring). For a plastic float, this is typically 12mm for the "closed" position and 25mm for the "open" position, but always verify the specific series of your 40 or 45 DCOE. An incorrect float level will cause the carburetor to run rich or lean regardless of how you adjust the mixture screws.

3. Don''t Over-Tighten the Soft Parts

The Weber DCOE body is made of a zinc alloy (Mazak) which can be easily stripped or warped. When installing the new gaskets and O-rings from this kit, remember that "snug" is better than "cranked." This is especially true for the top cover screws and the jet holders. Over-tightening the jet holders can deform the O-rings, leading to air leaks that make the engine impossible to sync. Use a drop of light machine oil on the O-rings during installation to help them slide into place without tearing. Proper torque ensures a vacuum-tight seal without risking expensive damage to the carburetor body.