310 information

[paulj]

Over the past few months, my engine has developed a coolant/antifreeze leakin the closed cooling circuit. The leak is at the aft end of the engine. Ihaven't eliminated the leak just yet, but wanted you all to be aware of foursources for such a leak:. One source is the coolant drain, which takes the form of a smallbronze screw next to the pencil zinc on the bottom starboard side of theheat exchanger. This tends to wiggle itself loose over time. Check itregularly.. A second is the connection of the thick wire-reinforced manifoldhose to the heat exchanger. Apparently due to the thickness and stiffness ofthe wire reinforcement, it can be difficult to get the hose clamp tightenough. Touch a paper towel to either of those points to see if there ismoisture. . Third, the plastic coolant surge tank tends to crack next to thehose nipple at the bottom. If yours hasn't cracked yet, definitely check itout.. There is a separate source of leaking for 310s built prior to minein 2002. It seems that earlier heat exchangers were attached to the engineby means of a bracket that could be a point of corrosion. Our 310Association Tech Editor, Bill Lewis, did a terrific job in the Mainsheetdescribing his work to resolve this issue. Just go tohttp://www.catalina310.org/MainsheetMagazine.htm and pull up the 2004 and2005 tech notes articles.Finally, I researched a bit the recommended coolant/antifreeze for theengine, since Westerbeke does not specify one. All you guys in the frostbelt probably know ALL about this, but it's not such a point of discussionin more temparate climes.First, use propylene glycol rather than the toxic ethylene glycol. Myauthorized Westerbeke diesel mechanic prefers to use a Dex-Cool extendedlife coolant, which he purchases from an auto supply place, and he says itis fine to use it up to five years between changes. He notes that our enginewill cycle hot and cold much less frequently than an automobile engine, andour engine operates at 160 degrees rather than the hotter automobile enginearound 220 degrees. However, West Marine's 1-gallon Seafit Antifreeze andCoolant is fine. It's easy, though, to be confused with the antifreeze thatis used for winterizing head and potable water systems, which do not containthe anti-corrosion additives of the engine antifreeze/coolant preparations.Our coolant system has about a one gallon capacity. Make sure to followdirections for dilution with distilled water. I understand part of theimportance for this is to avoid concentrations that can damage gaskets andother soft parts. Notwithstanding my diesel mechanic's practice, Westerbekerecommends a coolant change every two years. There was a good discussion onthis email list in April 2004 from Jon White, Gary Malcomson and PeteSandford. At the time it was noted:The trick of bleeding the air out of the system after refilling, was tofill, run the engine, loosen the valve near the thermostat until coolantcomes out, and repeat as many times as needed (about 3 or so). I wasn'tsuccsesful the first several times, and the engine would quickly over heat.I was very frustrated until I started really racing the engine (to about2,000 rpm). That seemed to push the air out and every thing has been finesince.Other good links:. West Marine article on antifreeze:http://www.westmarine.com/webapp/wcs/stores/servlet/westadvisor/10001/-1/10001/Antifreeze.htm . Detailed Sailboatowners coolant thread:http://archives.sailboatowners.com/pviewarch.htm?fno=400<http://archives.sailboatowners.com/pviewarch.htm?fno=400&sku=2007302170908.96&id=499705&ptl=Anti-Freeze%20%22Color%3F%22&id=499705>&sku=2007302170908.96&id=499705&ptl=Anti-Freeze%20%22Color%3F%22&id=499705. Westerbeke FAQs: http://www.westerbeke.com/technical/faq.cfm#38PAUL V. OLIVA, Skipper and ASA InstructorTime & Tide, Catalina 310 #179South Beach Harbor, D-79, San FranciscoOliva Global Communications442 POST STREET, SUITE 800SAN FRANCISCO, CA 94102 USA+1.415.235.5185www.olivaglobal.com <http://www.olivaglobal.com/> SKYPE: olivaglobal

 

[Stu Jackson]

Good input, Paul

Regarding your issue with overheating, see this link from earlier today, it could be that you have an air bubble in the line to your hot water heater. See my last reply (#8) to John about "burping": http://www.sailboatowners.com/forums/pviewall.tpl?fno=21&uid=73200280089&sku=2007332212652.1&rid=2007333111819.12#2007333111819.12