How many Type 4 carburetor engines (engine code CU) still have a working original return spring for the throttle linkage?
Very few indeed. Most original springs are so rusted that they are on the verge of breaking, or have been replaced by an alternative spring with incorrect tensile strength. the accelerator pedal will then start to feel much too heavy, or the opposite, and you won't be able to open the throttle fully because the spring is too weak.
The return spring mentioned here is identical in design to the original with the correct tensile strength.
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