Carburetor throttle shaft 40 PICB. Porsche 356 / 356 A-T1  ›  61610074100

Carburetor Throttle Shaft 40 PICB.

The OE Match Carburettor Throttle Shaft is a precision replacement component for compatible Solex 40 PICB carburettors fitted to early Porsche 356 applications.
This is a new shaft CNC machined and black zinc plated.

Fits:

• Porsche 356 Pre-A / 356 A with the 1500 S engine

Diagram Ref No 2

The throttle shaft passes through the carburettor body and carries the throttle butterfly or throttle plate. Movement from the accelerator linkage rotates the shaft, opening or closing the throttle plate to regulate the quantity of air and fuel mixture entering the engine.

Because the shaft operates every time the accelerator is pressed or released, both the shaft and the corresponding carburettor-body bores can wear over time. Excessive clearance can allow unwanted air to enter around the shaft, which may disturb the carburettor mixture and make accurate idle adjustment difficult.

This replacement shaft is CNC machined and black zinc plated, providing a precision replacement when rebuilding or restoring the original carburettor.

What This Product Does:

• Provides the pivot shaft for the carburettor throttle plate.
• Transfers accelerator-linkage movement to the throttle butterfly.
• Opens the throttle plate as the accelerator is pressed.
• Allows the throttle plate to close correctly when the accelerator is released.
• Helps maintain accurate throttle positioning.
• Supports stable idle and predictable throttle response.
• Helps maintain correct carburettor airflow control.
• Reduces excessive linkage movement when replacing a worn shaft.
• Helps restore correct carburettor operation during rebuilding.
• Provides a precision replacement for a worn, corroded or damaged original shaft.

The Porsche parts catalogue shows the throttle shaft working directly with the throttle valve, retaining screws, lever, seals and associated carburettor hardware.

Symptoms Of Wear Or Failure:
Possible symptoms include:

• Excessive sideways movement or play in the throttle shaft.
• Loose or imprecise throttle linkage.
• Unstable or inconsistent idle.
• Difficulty setting the idle speed correctly.
• Engine speed changing when the throttle shaft is moved sideways.
• Hesitation during initial throttle application.
• Poor or inconsistent throttle response.
• Engine running lean at idle.
• Carburettor mixture adjustment becoming difficult.
• Uneven running at low engine speeds.
• Throttle plate failing to return consistently to the same closed position.
• Sticking or stiff throttle movement.
• Visible shaft wear or scoring.
• Corrosion on the shaft.
• Excessive clearance between the shaft and carburettor body.

Current specialist cataloguing notes that throttle-shaft wear or excessive bore clearance can lead to poor throttle response, uneven idle and incorrect fuel metering.

Why Replacement Matters:
The carburettor depends on precise control of airflow through the throttle plate.

When the throttle shaft or its supporting bore becomes worn, the shaft can move laterally rather than simply rotating around its intended axis. This can affect both throttle-plate positioning and the sealing of the shaft within the carburettor body.

Excessive shaft clearance may allow unmetered air to enter the carburettor. Because this air bypasses the normal calibrated airflow path, the engine's air/fuel mixture can become difficult to control, particularly at idle and small throttle openings.

Replacing a worn throttle shaft helps restore:

• Accurate throttle movement.
• Reduced throttle linkage play.
• More consistent throttle-plate positioning.
• Improved idle stability.
• More predictable throttle response.
• Correct carburettor adjustment.
• Reliable operation of the accelerator linkage.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

61610074100

The product you are viewing cross references to these numbers