Thanks Don. I must be in pretty good shape as I can run at 3000 rpm without overheating. I am sure that in 82 degree water I probably would be limited to 2000 to 2500 rpm. By the way, our boats must be aquainted as mine is hull # 6298.
--- In [email protected], Don Brooks <brooksd...@...> wrote: > > I am not sure if "undersized" is the right word for the heat exchanger on the > M18. "Barely adequate" sound more like it. Especially, if you sail in 85 > degree water like we do in FL. In cold water like you have, it should do > just fine. It is probably normal to overheat at WOT. You should be > running continuous between 2,100 and 2,600 rpm. That should give you > between 5.2 to 5.8kts, depending on your prop being clean and how much junk > you carry on board. Max rpm is 3,200 and you should not do that much for > over 5 minutes. > Don, #6293, Niceville, FL > > --- On Sun, 2/14/10, dalzellandrew97 <acdalz...@...> wrote: > > > From: dalzellandrew97 <acdalz...@...> > Subject: [IC27A] Heat exchangers > To: [email protected] > Date: Sunday, February 14, 2010, 10:21 AM > > >  > > > > Some of my fellow Catalina 27 and 30 owners have told me that they have read > that many Catalinas that have Universal Diesels are equiped with undersized > heat exchangers. . I can run all day at 3000 RPM in 68 degree water on Lake > Erie and maintain an engine temp of 160-165 degrees. However, if I go full > throttle (3700-3800 RPM on my tach) the temp will climb to 0ver 200 degrees. > I have replaced my impeller on a regular basis and checked the heat exchanger > by removing the end cap to look for obstructions and check the zinc anode. I > have also cleaned my raw water inlet strainer regularly and it looks clear. > My boat is a 1986 model equipped with a Universal M-18 2-cylinder diesel that > has only 220 hours on the meter. I seem to get plenty of cooling water flow > out of my exhaust. > > Is there a chance that my OEM heat exchanger is undersized and should be > replaced? If so, who sells them and what would I ask for? Are there any > special installation problems? > > > > > > > > > > > > [Non-text portions of this message have been removed] >
