I have a mercury 2000 4-stroke 40hp outboard (bigfoot) the engine has overheated on the last two trips out. It happens shortly after leaving the dock at about 2/3 throttle. both times I shut the engine down and allowed it to cool and it would then run at slower speeds without trouble. I replaced the water pump this morning (impeller was cracked and case was worn). After reinstalling and running in a barrel of water I found that the tell tale flow is intermittant wavering between weak and strong. The overheat warning actually went off running it in the barrel. I have read some of the other postings and sounds like I could have a clog somewhere in the system. How do I approach this, or any other suggestions? <br />Thanks!
