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?
