Hi All, I have a Yanmar 3TNE84MT-EG1. Over the last several hundred hours, the impeller longevity has slowly declined. They used to last up to 400 hours, then 250, then 150 at which point my parts dealer suggested that I change out the cover plate, which did have scoring on it. I changed that, installed a brand new impeller, tested to determine if there were any leaks and that I had a good stream coming out of the exhaust. All was good. I shut it down and left it alone for a month. I started it yesterday, water was passing through the exhaust perfectly but after five minutes I saw an alarm on the remote panel, ran to the stern, looked overboard and saw zero water coming from the exhaust at which point I of course shut down the genset. Before I change the entire water pump, what inside the pump could be causing this phenomenon? I don't want to change the pump unless I have to and certainly not if I can make a simple repair to keep the existing one in service. What should I do and why? Thanks. Jim -- Jim Felds M/Y Kokomo Hatteras 48 LRC US Phone: 910-352-7119 Caribbean: 590-6600-96453 Jim@Focustarcapital.com www.LifeonKokomo.com (Blog)

Hi Jim, A couple questions: Does the impeller have broken or missing vanes? How's the shaft? Anything else bent, broken, missing, or other flaw present. It'd be hard to suggest the problem unless the pump is pulled apart and inspected. Keep us informed. *Rudy & Jill Sechez * *BRINEY BUG-a 34' Sail-Assisted Trawler * *Anchoring Consultants-trawlertrainingabc.com* *850-832-7748 * *Carolina Bch SC Northbound-Chesapeake* > > <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free. www.avg.com <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Another thought, Jim, is the pump getting water to it. If the pump sits below the waterline, remove the water hose from the pump and see if water flows out. There may be a clog somewhere, not allowing water to get to the pump. If this is the case, I'd expect to see damaged vanes on the impeller. *Rudy & Jill Sechez * *BRINEY BUG-a 34' Sail-Assisted Trawler * *Anchoring Consultants-trawlertrainingabc.com* *850-832-7748 * *Carolina Bch SC Northbound-Chesapeake* > > <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> Virus-free. www.avg.com <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

> Before I change the entire water pump, what inside the pump could be > causing this phenomenon? Worn or damaged cam. And if you are replacing the cam, you should also replace the wear plate. -Sean m/y Vector lying Awendaw Creek, SC http://OurOdyssey.BlogSpot.com