Dream Quest
Member
My 2000 Mainship 390 has a single 300hp Cat engine. If I warm the engine up before leaving the engine temperature gauge stays at around 175 degrees which is normal. When I stop and then later restart the engine the temperature invariably climbs to over 200 degrees at which time I of course shut the engine down. If I wait a few minutes the gauge quickly drops back to normal range and I am able to continue on. I replaced the temperature regulator (thermostat) but the problem persists. The engine does not appear to me to be actually overheating. Both the upper and lower helm gauges give the same readings. Any suggestions?