Any ideas?<br /> took boat out first time this year after sitting about 5 months. Engine cranked fine, idled out and took off down the lake. About 30-40 seconds after planing off, the overheat horn went off.I immediately shut it down and waited a few minutes and tried again. Same thing. Here's what i've done so far replaced temp sensor, rebuilt water pump with kit, installed both new thermostats and inspected relief valve.I installed a water temp gauge and it shows 160-170 degrees idling, and drops drastically during accel down to around 100-110 degrees. Can't tell much after that due to horn going off. Engine ran excellent last year. What changed?
