Governors & Actuators
The hardware that holds a diesel engine at frequency under changing load — GAC electronic governors, actuators, magnetic pickups and the linkages between them.
Speed control for diesel engines
Governors America Corp make the speed governing hardware that holds a diesel engine at frequency under changing load. We stock the range in Brisbane: electronic speed control units, the actuators they drive, magnetic speed pickups, and the harnesses, brackets and linkages that connect them.
Most enquiries here are replacements for a failed unit on an existing set. If you have the part number from the old unit, find it below. If you only have the engine and the symptom — hunting, drooping under load, failing to reach rated speed — send us those and we will work out what you need.
Advantages of GAC Governing Hardware
The governor, actuator, pickup and linkage on a set have to match each other before they can hold the engine at frequency. Buying them from one range, with the fitting parts, removes that guesswork.
Direct replacements
The ESD5500-II replaces most ESD5500E units on the same wiring, and the EEG6500 shares the ESD5500E mounting pattern, so a failed governor on an existing set is a like-for-like swap.
The whole speed loop
Speed control units, the actuators they drive, MSP magnetic pickups in the common thread sizes, and the harnesses, brackets, rods and levers that connect them.
Set up on the unit
The EEG6500's display and push buttons let a technician set speed, droop and ramp on site with no laptop, and lock the display afterwards.
Key Features
- ESD5500-II and EEG6500 speed control units, isochronous or droop
- P-pump, throttle body and proportional actuators, with installation kits
- MSP magnetic pickups in M16 x 1.5, M18 x 1.5, 3/4-16 UNF and 5/8-18 UNF
- Harnesses, connectors, brackets, rods and levers to complete the fit
Governor and Actuator FAQ
The ESD5500-II. GAC built it as a single replacement for most of the ESD5500E series, on a multi-voltage DC supply, with adjustable droop and idle, selectable light-force and dither, speed ramping and anti-windup for diesel and gas engines. A high-frequency version handles pickup inputs to 14 kHz. It works with GAC proportional actuators other than the ACB2001.
Setup. The EEG6500 has a built-in LCD and five push buttons, so you set rated speed, idle, droop and ramp on the front of the unit without a potentiometer or a PC, and it shows engine frequency as you go. It also outputs engine speed over J1939 and has an auxiliary input for synchronising and load sharing. It uses the same mounting-hole pattern as the ESD5500E, and works with GAC actuators other than the ATB T4 series, the ADB335 and the ACB2001.
Match the thread on the flywheel housing boss: the MSP range covers M16 x 1.5, M18 x 1.5, 3/4-16 UNF and 5/8-18 UNF. Then match the thread length to the boss and the harness connector to the governor. MSP pickups need no energising supply from the controller and work with all GAC electronic speed controllers. Measure the old pickup's thread and length before ordering.
On a Bosch P-pump, yes. The ADD175A-12 mounts on the pump and connects to the fuel rack in place of the mechanical governor, for a right-hand rack, with a 12/24 V DC supply, a manual shut-off and a response under 35 ms. It ships with the KT289 Bosch installation kit. For other pumps and engines, send us the engine model and a photo of the pump and we will match the actuator and linkage.
Any of the three, and the symptom on its own does not say which. A slipping or loose linkage, a pickup with the wrong gap or a failing actuator can each look like a governor fault. Send us the engine model, the governor and actuator part numbers and a description of the symptom, and we will work through it with you before you buy a part.
With the TSE050 frequency generator. It simulates a magnetic pickup signal from 750 Hz to 10 kHz on a 6 to 30 V DC supply, so you can bench-test a speed control unit or check its response without cranking anything.
Talk to an engineer
Have questions or need assistance? Our team is ready to help you via email, phone, not a chatbot.
Latest Blogs
Our team is ready to help!
If you have any questions, need further information, feel free to reach out, and we'll get back to you as soon as possible. We look forward to hearing from you!