Volvo penta tamd71a overheating problem..

[Celik2828]

The engine also started to have an overheating problem. After 2000rpm, it slows down. After driving on the road for a while, the alarm goes off. When it slows down, it cools down quickly. The engine was completely overhauled last year, I tried it many times and there was no problem. A year has passed and this problem started recently. In this process, I started looking for the problem from Jabsco and renewed the repair kit. Condensates and aftercooler were cleaned. The thermostat and heat sensor were tested. Even though the fresh water pump was revised last year, I changed the repair kit again. I also tried the engine without a thermostat and the problem still persists. And every time I go on a new sea voyage, the warm-up time gets shorter. That means there is a blockage somewhere. I think so. By the way, there is no pressure or compressor in the backup water boiler.