I have a newly acquired 1985 Catalina 30 with a factory installed M25 that we are rebuilding. The boat was neglected by non-use for an undisclosed amount of time, but likely 12-18 months. The head gasket was blown and coolant was in the pistons. We sent the head to a machine shop and replaced valves, seats, push rods and seals on the top of the motor. We were able to fire it up, but it does not respond to the throttle. It immediately races and has to be stopped by the decompression valve or by blocking the air intake. (The good news is that it sounds good) But obviously, we have to get this under control asap. I know very little about diesel engines which is why I hired a mechanic (who has been working on diesels for about 30 years). He thinks it may be a governor problem.
It can be clearly seen that the throttle moves back and forth without any change in speed--it accelerates past the redline. The throttle lever on the helm is very stiff but does move. The lever on the port-side ( I presume to be the transmission selector) does not. I think this should be a separate issue, but do not really know. The overall appearance of the motor is quiet good.
I know in some marine diesels, the governor is located in the high-pressure fuel pump. Does anyone know the location of the governor in a Kubota D 850 or have any idea where else to look or what else it could be. Even with the throttle on the engine all the way in the idle position, it still races
When we start the motor, we have around five seconds to make observations before it revs in the critical range and we have to shut down.
It can be clearly seen that the throttle moves back and forth without any change in speed--it accelerates past the redline. The throttle lever on the helm is very stiff but does move. The lever on the port-side ( I presume to be the transmission selector) does not. I think this should be a separate issue, but do not really know. The overall appearance of the motor is quiet good.
I know in some marine diesels, the governor is located in the high-pressure fuel pump. Does anyone know the location of the governor in a Kubota D 850 or have any idea where else to look or what else it could be. Even with the throttle on the engine all the way in the idle position, it still races
When we start the motor, we have around five seconds to make observations before it revs in the critical range and we have to shut down.
