Hello, We are running W12V32’s, and one of our engines starts to “use or lose” HT water when the engine load goes down below 80 percent. The HT water level in the expansion tank drops by approx. 5 gallons per hour. We cannot find any leaks in the cooling system, and all the valves appear to be fully operational. There are no signs of HT water jacket leaks at the cylinders via exterior inspection and no signs of water in the oil sump.
I can only speculate that the water is going into the cylinders, but my cylinder temps are not showing any variations and are perfectly in range and perfectly consistent with our other engines.
When blowing down (purging) the engine during engine offline periods, no noticeable water is expelled from the purge cocks.
Another interesting thing is that when the engine load returns to levels at or above 80 percent, the issue resolves itself within 24-48 hours. It always takes 24-48 to return to normal. In other words, the HT water levels remain constant in the expansion tank when the engine runs at 80 percent load.
We are not in a position operationally to shutdown the engine and do bore scopes to see if water is in the cylinders at this time.
Does anyone here have any ideas on why this could be happening? Or what else we can troubleshoot?