Reply
Super Contributor

Re: Cat speed brick low idle

With throttles at lowest position, throttle signal duty cycle should be 6-8%. Full throttle duty cycle should be 90-92%. Program/adjust controls for that spec and idle will be normal. FYI engines idle better at 650-700 RPM and should be programmed accordingly.
New member

Re: Cat speed brick low idle

Yes that’s correct. The speed brick is actually incorporated into the MECS system, NOT the cat system. I have completely iscolated the mecs system and I cry my 600rpm low idle back. however I’m getting throttle position input as soon as the MECS is brought back online.
Super Contributor

Re: Cat speed brick low idle

Engine idle speed is programmed in the engine ECM and has nothing to do with the "speed brick". Idle should be 700 RPM. When slow vessel mode is enabled, idle drops to 550 RPM. SVM used for short periods of time only, usually just docking.
New member

Cat speed brick low idle

Hi all. Wondering if anyone has any info on idle parameters for the cat speed brick in combination with the Hamilton Jet MECS system? We have 2 utility vessels, twin jet C18’s @ 860 hp. Both vessels have different low idle values. Problem has been iscolated to the speed brick resistors. Speed bricks have both been replaced with new, but no fix. However resistors swapped between engines and the problem shifts. Anybody know what the OHM value of the resistors are meant to be? Resistor for each brick is between pin 2 and pin B. Speed bricks are 9X9857.
THANKS
jack.