I have a 1997 Yanmar 3JH-2TE (turbo) with 5500 hours on it which is overheating when I push the RPMs above 2500. At 2500 I'm at 185, and it goes up from there. This has been going on for multiple years, but is getting worse, meaning the the highest RPM that I can run at is dropping. Several years ago I could run at 2800.
Last year I did an extensive overhaul of the engine which included the following:
Thanks for any suggestions that you can provide! -- Geoff
Last year I did an extensive overhaul of the engine which included the following:
- Removed and acid-boiled the heat exchanger
- Replaced the thermostat
- Removed and inspected the mixing elbow - like new
- Replaced water hoses to mixing elbow
- Replaced the raw water pump and impeller. The water flow is good out of the exhaust.
- Replaced the water hose to the heat exchanger
- Flushed cooling system with fresh water until it ran clear. This was done on the hard, so the engine wasn't run.
- Replaced coolant - red. Completely full upon inspection. Expansion tank full.
- Replaced some hoses
- Mechanical stuff like replacing motor mounts, clutch work, transmission work, etc
Thanks for any suggestions that you can provide! -- Geoff