High jacket water temperature at cylinder outlet for all units –
- Jacket cooling water temperature controller defective
- The jacket water cooler is ineffective (due to a choked cooler, less cooling media, etc.)
- The discharge pressure of the jacket cooling water pump is low
- The engine is overloaded.
High jacket water temperature at cylinder outlet for the individual unit –
- Jacket water outlet line valves of the affected cylinders are shut or defective.
- Cooling spaces are insufficiently vented.
- Cooling water pipes or water passages choked.
- Overloading of affected cylinders.
- Piston running hot.
- Exhaust gases blow into the cooling water circuit due to a defect (cylinder liner, cylinder head, valve, and cage).
Jacket cooling water pressure fluctuates
- Air collecting in the cooling spaces or in the pipes due to insufficient venting.
- A drop of static pressure at the inlet to the cooling water pump due to throttling in the return pipe or draining of the expansion tank.
- Exhaust gases blowing into the cooling water due to a defect (cylinder liner, cylinder head, valve