Which engines can the electronic throttle/speed control kit be fitted to?
It fits diesel and petrol engines whose butterfly or injection pump lever is driven mechanically; on a drive-by-wire engine there is no lever left to drive.
The kit is fitted to diesel and petrol engines whose throttle butterfly or injection pump lever is driven mechanically — by a cable or by a lever. The make of the engine, its number of cylinders and its age are not decisive; what is decisive is the presence of a throttle lever that can be reached from outside and moves freely. The supply is 12V or 24V DC.
Where on the engine the kit is connected
If the engine has a throttle lever pushed by hand, or a joint to which a cable is attached, the kit works in parallel with it: the cable-pull servo drives the position of the lever in your place. On most diesels the connection point is the injection pump throttle lever on top of the injection pump; on petrol engines the carburettor lever does the same job. The original lever is not removed, it stays in place and can be used by hand when needed.
Fits, does not fit: the quick check
| Engine | Situation | Reason |
|---|---|---|
| Diesel with a mechanical throttle lever (tractor, irrigation engine, generator, drilling rig, earthmoving machine) | Fits | The cable drives the lever directly |
| Petrol engine with a mechanical throttle lever | Fits | The same mechanical point is present |
| Engine with a seized lever or a worn joint | Repair first | A lever that sticks is not put right by electronics either |
| Fully electronic throttle (drive-by-wire) engine | Does not fit | The butterfly is driven by the ECU; there is no mechanical lever to drive |
If you are not sure which group you are in, look behind the throttle pedal or the lever: if you see a cable it is mechanical, and if you see only a connector and a wiring loom it is electronic. The difference between the two systems is described separately. On engines with an electronic throttle the intervention is made not over the lever but over the engine's own signal chain.
The lever itself is checked before installation
With the engine stopped, take the lever from idle to fully open with your finger and let it go. The lever should move without catching and return to idle under its own spring when released. If there is play, rust or stiffness in the joint, put that right first; otherwise a significant part of the pulling force of the kit is spent on mechanical resistance, and no electronic adjustment makes up for it. How the installation is done without removing the original lever is a separate subject; thanks to the piggyback fitting, which requires no dismantling, the engine returns to its original state when the kit is taken off.
Even on an engine that fits, the mounting position is chosen
The kit fitting does not mean you can put the servo anywhere. The mounting point has three conditions to meet: it has to be away from hot surfaces such as the exhaust manifold, it has to be fastened to a solid surface that does not amplify vibration, and it has to let the cable reach the lever along as straight a line as possible. If no point satisfying all three can be found, the cable gets longer, the number of bends grows, the friction increases and it becomes harder for the lever to return to idle under its own spring. Decide the mounting position before you run the wiring; moving it afterwards means redoing both the cable and the wiring.
What the kit does not cover
The kit does not take the place of the mechanical governor of the engine: the governor stays on the engine and the kit only sets the position of the throttle lever. The practical consequences of that distinction are dealt with in detail. In the same way, overspeed protection, emergency stopping and oil pressure and temperature protection have to be present in the engine's own system and must not be expected from the kit. Do not remove or bridge the existing protective devices because a kit has been fitted; the kit takes the place of none of them.
When making the decision
Go and stand beside the engine and answer one question: is there a throttle lever you can push by hand, and does it move freely? If both answers are yes, the kit fits. The GS740 is used for a single engine and the GS740-3P for three independent engines; both carry a 36-month warranty. Where you cannot be sure of the mounting geometry, take a photograph of the lever and its surroundings and consult us.
The full topic: Electronic speed and throttle control on diesel engines