New C-30 Owner

[Lou Gentile]

I have recently purchased a 1984 Catalina 30, powered by a Universal 25 HP diesel. The boat runs fine, but I have several questions. At full throttle it runs at 2000 RPMs and makes about 6.3 or 6.4 knots. At this level the temperature is up to 205 to 210 degrees. At 1700/1800 the engine runs at 190/200 degrees and the boat makes 5.9/6.0 knots. I have been told that the prop on the boat is not original and is oversized but not a three blade.My questions are, is this engine running to hot? Has this prop because of its size, reduced RPMs? Is all this OK or do I have to correct something?PS. brought this boat in from a 14 hour trip, non stop motored the entire way no overheating ran at 1800 RPMs for hours on end, temperature at 200. The engine is fresh water cooled.

 

[Dave Emery]

Engine / Prop Combo

I would check your RPM capabilities in neutral. Move the throttle to full for a COUPLE of seconds and observe the RPM's. This engine should rev to approximatly 3300 rpm's. Assuming this is the case, I would suspect that the prop is incorrect. This engine also has an operating tempature of 165 - 185 degrees. I beleive 200 degrees would be considered running hot. You appear to be acheiving 6+ knots at two low of RPM's which again sounds like the wrong prop and would be putting an unnecessary load on the engine causing high tempature. Good Luck!

 

[James]

Another place to look

Lou,If it turns out you aren't over-propped, another place to check is the raw water heat exchanger. The heat exchanger tends to accumulate sludge and sometimes will partially plug, causing the engine to run hot. I've seen this on a number of boats, and these should be inspected every few years in normal service.Also, the M-25 should max out at 3,000 rpm as it is controlled by a governor for overspeed. Good luck with your new boat.

 

[John Mavrovich]

New C30 Owner

Lou, your engine should run at about 160 degrees. It should also be run at 2700 rpm for top speed. I suggest you change the prop to the one recommended for that boat/engine. Catalina may know this.

 

[kemah sailor]

prop change

lou,i have an 85 cat.30 with the univ.25i run mine at 2600 rpm at a temp of 160degrees.call catalina service dept.re.this issue.a 3 bladed prop would be alotmore efficient.sounds to me like thereis more of a problem than the prop.tryflushin the system and change theimpeller.