peninsular beast in '97 28 TE

[danwarman]

Last year eng. temp was 195-200 at 3000 plus. On first trip BEFORE maintenance, the alarm went off (low oil press. I believe) and I replaced oil with rotella 40. No alarm after that.

This year I changed oil and used rotella 40 but temps are a little higher 200-210 at 3000 rpm. This is a little too high for engine according to Peninsular. Alarm goes off after running at this a while. When I slow to 2500, eng temps. drop and alarm stops. If I increase rpms, it goes off again. Could be oil press., could be water temp. (heat exchanger, pump flow etc.), could be sensitve alarm. I did not replace antifreeze for 2 years. Impeller replaced less than a year ago. Oil level and coolant level are correct.

Any guidance. I called peninsular and they suggested cleaning of heat exchanger. My experience is that once you start to take things apart, something new is found.

Any recommendations as to order of solutions, flush with something?, replace antifreeze?, replace 10 month old impeller? clean heat exchanger?

Engine has been very well maintained and is as clean as any there is of this age. Not too many hours, 800 or so.

[Dexter]

The heat exchanger is very easy to clean. There are side caps that unbolt and come off easily. Did mine, just prepare for water to come out. Drain the raw water side first. they may be clogged. I found that a bb gun cleaner rod works well to clean all the tubes. These engines are real easy to work on.

[jcollins]

Even after a vinegar flush last season my WOT temp was 200. This year I had the heat exchanger pulled and cleaned, fresh antifreeze. My WOT temp is 180. Cruising temp is 165-170. I also have a new seawater pump. According to Matt at Peninsular, 200-205 is the upper limit.

[Dexter]

Another note, I am in the process of replacing my peninsulars. One blew, doing both. When I tool off the exhaust system I found that the ports were full of gunk. I have been flushing and brushing them out. Amazing how much crap builds up over the years. I also found some of the ports clogged.

[MarkG56]

I just went through the same problem. The first thing I did was pull the raw water impeller and that was it. After replacement all systems normal....

[MarkG56]

Another note, after I got a high temp. alarm I throttled back and got home at 10 knots holding temp. due to flow through my intake scoop. At idle temp. spiked again at the dock pointing to lack of raw water flow. Simple fix, don't assume your new impeller is still good...