Hello,<br />I have a problem which reoccours every year for the past three years.<br />When I start the boat and let it idle to warm up the temp will slowly climb up into the red zone. Now, here is the kicker. One quick rev and the temp drops to 140 and will stay there all day. I can run wide open or idle no problems. If I shut the boat off and restart same broblem.Here is a list of parts changed:<br /><br />Impeller, from pump base to housing every year<br />Water pocket cover <br />risers <br />nylon balls in brass tee<br />Thermostat housing<br />Thermostat evey year<br />all ON engine hoses<br />back flushed hose with oil cooler in it.<br />I should mention the idle is very low 550 rpm. I was told the idle should be set as low as the engine will run to help save the drive when shifting <br />Although the problem is manageable I would like to know what is going on here.<br /><br /> Thank you in advance for your advice, AL
