FORUM RULES UPDATED - The forum rules have been updated to continue to provide a friendly and safe environment for our member community. Please take a moment to review the updated rules and our terms of use and privacy policy. Click here for Forum Rules which has links to the 'terms of use' and 'privacy policy'.
In Other News . . .
You will notice a few enchancements to the forums to make your experience better. These include: Email Notifications, Thread Previews, Thread Starter Notation, and Emoji Options on the 'Like' icon. . .
Additionally, the merchant portions of the website have been updated and are now operational. . . . Check out iBoats for all your boating gear.
Have 2007 Mercury Optimax 150. After 10 minute run at 3000 rpm engine warning buzzer starts and engine cuts back to1000 rpm or almost idle. Mechanics many trips and quite some costs was never able to determine problem. Impeller was replaced.
I just had a thought. A thermostat and gauge would tell you if overheat is the problem or something else. On a different engine and surely on that one too, temperature is controlled by thermostats in each bank and a high RPM popoff valve allowing for increased flow at the higher RPMs. A malfunctioning popoff or clogs in your cooling system could be the culprit. Again, knowing if overheating is the issue helps to direct you to the culprit....would me.
Thanks for the suggestion but engine does not overheat. Mechanic is coming tomorrow with borrowed testing device that should give a diagnosis. Luck is needed.
