Re: 87' 9.9 hp.Mercury
Check that the water pickups aren't clogged with any debris. If the motor has a thermostat, remove it and if water flows...time for a new t-stat. Get some small wire and stick it up the tell-tale and try to scrape out any crap that may have gotten stuck up there.<br /><br />Even though you had the impeller replaced last year it could be damaged. I replaced mine in 04' and this summer had to replace again because the inner hub of the impeller had spun.