Fred: What is going to make the seawater circulate through the engine? Are you going to the raw water pump to circulate seawater through the engine’s cavity? I would think that the volume of seawater circulated would need to be greater than the antifreeze/water mixture normally in the closed cooling system since it is less efficient in heat exchange but there may be enough seawater that would be pumped by the raw water pump. You might find that the temperarture will run a little higher than normal.
> On Aug 9, 2019, at 2:04 PM, Frederick G Street via CnC-List > <cnc-list@cnc-list.com> wrote: > > Hello, all — I’ve got a 1979 LF38 with the original Yanmar 3QM diesel, fitted > with a Sendure fresh-water exchanger kit (also original). > > Over the last season or so, I’ve been noticing a slow but accelerating drop > in the coolant level. In the last month, it has sped up quite a lot. It’s > not getting into the oil, and the head gasket is relatively new. With the > recent acceleration, there’s also a lot of white smoke (steam) in the exhaust > as well. > > I’m thinking the heat exchanger may have developed a leak (or leaks) between > the fresh and raw water sides. I’m going to pull it this weekend and test it > to see if that’s the case. I am also going to replace ALL coolant hoses > (fresh and raw, including the loops to the water heater and the v-drive). I > ordered 50 feet of 1/2” and 3/4” Gates green-stripe (off Amazon) to keep > costs lower per foot and make sure I have enough; this may also allow me to > perform a temporary fix in case the exchanger is toast, by completely > bypassing the Sendure system and effectively making the engine raw-water > cooled until I can decide what to do with the exchanger. This would also > allow me to go on an extended weekend cruise next weekend without worry. > BTW, so that I don’t have to try to size new belts for the engine, I’ll leave > the add-on coolant pump in place, but remove the impeller and just let it > freewheel for the temporary fix (with no hoses connected). It’s fairly new, > I replaced it a few years ago. > > Anyone see any downsides to this plan; or any other places I can look for the > missing coolant? 🙂 > > — Fred > > > > Fred Street -- Minneapolis > S/V Oceanis (1979 C&C Landfall 38) -- Bayfield, WI > > _______________________________________________ > > Thanks everyone for supporting this list with your contributions. Each and > every one is greatly appreciated. If you want to support the list - use > PayPal to send contribution -- https://www.paypal.me/stumurray > Robert Boyer s/v Rainy Days C&C Landfall 38, Hull #230 411 Walnut Street #11447 Green Cove Springs, FL 32043 (443) 994-1802
_______________________________________________ Thanks everyone for supporting this list with your contributions. Each and every one is greatly appreciated. If you want to support the list - use PayPal to send contribution -- https://www.paypal.me/stumurray
