Porsche Solex Carb Parts: A Comprehensive Guide

Restoring or maintaining a classic Porsche with Solex carburetors requires understanding the specific parts that keep these engines running smoothly. Whether you own a 356, 912, or early 911, sourcing the right Porsche Solex carb parts is essential for reliable performance and originality. This guide covers what you need to know about rebuilding kits, gaskets, jets, and more, plus practical advice for choosing components and avoiding common pitfalls.

Understanding Porsche Solex Carburetors

Solex carburetors were used on many Porsche models from the 1950s through the early 1970s. They are known for their mechanical reliability but require careful maintenance due to age and wear.

Common Models and Applications

Porsche used several Solex models:

• Solex 40 PII: Found on early 356 and 912 engines.
• Solex 40 PBIC: Used on some 356 SC and 912 models.
• Solex 40 PI: Appeared on early 911T and 911L variants.
• Solex 32 NDIX: Fitted on 356 B/C and some 912 models.

Carburetors were often paired in dual or triple configurations. Knowing your exact model is the first step to finding correct parts.

Key Components and Wear Items

Over time, rubber seals harden, gaskets leak, and jets clog. Common wear items include:

• Accelerator pump diaphragms
• Float needles and seats
• Throttle shaft bushings
• Gaskets (base, flange, top cover)
• Jets (main, idle, air correction)

Essential Porsche Solex Carb Parts

When rebuilding, focus on the parts that directly affect fuel metering and air sealing.

Rebuilding Kits

Complete rebuild kits save time and ensure you have all necessary gaskets and seals. Look for kits specific to your Solex model. Quality kits include:

• Gasket set (float bowl lid, base, throttle shaft, accelerator pump)
• Fuel inlet needle and seat
• Accelerator pump diaphragm and spring
• O-rings for mixture screws
• Emulsion tubes (if needed)

Some kits also include idle mixture screws and gaskets for the bowl drain plugs.

Gaskets and Seals

Separate gasket sets are available without the hardware. Use only cork or fiber gaskets that resist modern ethanol fuels. Avoid cheap paper gaskets that fail quickly. For throttle shafts, buy OEM-style O-rings or Teflon seals.

Jets and Needles

Jet sizes are stamped with numbers (e.g., main jet 125). If your car runs rich or lean, adjusting jet sizes can help. Stock jetting is usually best for street driving. Aftermarket jets are available in precision sizes. Always use genuine or high-quality repro jets; cheap ones can cause erratic running.

Throttle Shafts and Bushings

Worn throttle shafts create vacuum leaks and sticking. Replace worn shafts and ream bushings to proper size. Some suppliers sell re-bushing kits with pre-sized shafts. This is a more involved repair but critical for smooth operation.

Float and Valve Assemblies

Check float height and needle valve function. Original brass floats eventually sink; replace with new brass or plastic floats. Needle valves should have viton tips for ethanol compatibility. Set float level per factory specs (typically 10mm from gasket surface).

Sourcing Parts: OEM vs Aftermarket

Genuine Porsche Parts

Genuine Porsche Solex carb parts are still available for some models but can be expensive. They are usually the best choice for originality and fit. Check with Porsche Classic or authorized dealers. Many parts are NOS (new old stock), so verify condition before buying.

Quality Aftermarket Manufacturers

Several aftermarket sources produce reliable replacements:

• World Carburetor – offers complete rebuild kits for most Solex models.
• Carburetor Parts Warehouse – stocks jets, gaskets, and hard parts.
• K & L Supply – known for precision jets and needles.
• Classic Carburetor – sells rebushed throttle shafts and specialty parts.

For common models like 40 PII, you can find good aftermarket alternatives. Avoid unbranded parts from online auction sites; they often have poor tolerances.

What to Avoid

• Resin or plastic fuel filters that dissolve in ethanol.
• Gasket sets that include only paper gaskets – too brittle.
• Rebuilt carburetors from unknown sources – quality varies.
• Universal “one-size-fits-all” rebuild kits that don’t match your Solex model.

Rebuilding Tips for Porsche Solex Carbs

Tools Required

• Carburetor rebuild stand or clean workspace
• Screwdrivers (JIS cross-head for original screws)
• Torque wrench (small inch-lb range)
• Jet cleaning tool or small wire brushes
• Calipers for measuring float height
• Carburetor cleaner (non-chlorinated)

Step-by-Step Guidance

1. Disassembly: Carefully remove the carburetor from the intake manifold. Keep linkage and fasteners organized.
2. Clean all parts: Soak metal parts in carburetor cleaner, then blow out passages with compressed air. Do not gum up emulsion tubes.
3. Inspect: Check throttle shaft play, float condition, and needle seat sealing.
4. Replace wear items: Install new gaskets, seals, and any worn hard parts.
5. Rebuild: Assemble with new accelerator pump, float assembly, and jets. Set float height accurately.
6. Bench test: Manually operate throttle and accelerator pump to confirm movement and fuel delivery.
7. Install and synchronize: Mount carburetors, attach linkage, and balance airflow with a synchronizer tool.

Common Issues and Solutions

Vacuum Leaks

Vacuum leaks cause lean mixtures, rough idle, and hesitation. Common leak points: throttle shaft bore, base gasket, and manifold gaskets. Use a propane torch (unlit) or carburetor spray to locate leaks – if engine speed changes, you found the leak.

Solution: Replace throttle shaft bushings, use new gaskets, and tighten mounting nuts to spec.

Fuel Mixture Problems

If your Porsche runs rich (sooty plugs, black smoke) or lean (surging, backfiring), check:

• Float level – correct gap within 1mm.
• Jet cleanliness – use jet cleaning wire.
• Air correction jets – size too small causes richness.
• Idle mixture screws – adjust to peak vacuum.

Final Recommendations

For most owners, purchasing a complete rebuild kit specific to your Solex model is the smartest approach. Brands like World Carburetor and K & L Supply offer reliable parts. For throttle shaft work, consider sending the carb to a specialist unless you have proper tools. Keep jets and original hard parts as spares. Always double-check float height and gasket compatibility with modern fuel. With the right Porsche Solex carb parts and careful assembly, your classic Porsche will run like new.