Does the engine's original throttle lever have to be removed when fitting the kit?

No. The GS740 is designed for non-invasive add-on installation; the mechanical throttle lever and the engine's own governor stay in place. The cable-pull servo is connected in parallel at the point the lever pulls and takes the lever to the desired position. The throttle lever can also be used by hand when needed; when the kit is out of service the engine keeps running mechanically.

The installation logic is to add to the existing mechanism, not to replace it.

The practical benefits of this approach:

Things to check before installation: make sure the lever moves without binding over its whole stroke, eliminate play in the joints, and verify that the return spring is strong enough to bring it fully back to idle. A binding mechanism strains the servo; on the GS740-3P this makes itself known by hitting the current limit (factory setting approximately 7A). Do not mount the servo directly on hot spots such as the turbo/exhaust or at the points of highest vibration.

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