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#21
posted to rec.boats
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seagweed and cooling system
On 7/10/2011 3:24 PM, Wayne B wrote:
On Sun, 10 Jul 2011 08:01:28 -0400, wrote: On 7/9/2011 11:37 PM, Wayne B wrote: On Sat, 09 Jul 2011 17:30:26 -0400, wrote: Bob should install water temp and oil pressure gauges. Also an audible idiot alarm and maybe an idiot light. He could use the same audible idiot alarm for both water and oil. It has been proven that water temp gauges do a great job of telling you when it is already too late. No joke, usually the damage is done unless you catch it very quickly. There are two different sensors that can alert you in time: The first is a raw water pressure sensor/alarm installed downstream of the raw water pump. The second is a temperature sensor/alarm at the exhaust elbow. Either or both of these give you enough warning time to shut down before damage occurs. Many modern engines have both. A lot of folks don't glance at their instruments often enough. In bobs case, a gauge or horn probably would have alerted him to problems. Also the steam coming out the exhaust usually foretells engine damage. Misfiring or backfiring could also be a warning sign. Or if the engine slows down without any other signs you might be experiencing engine seizure. I'm not trying to scare bob, but he needs to pay attention better. My point was that no one can watch their gauges every second, and warning alarms usually go off too late to save damage. Most engines have some sort of audible alarm for high cylinder head temperature and low oil pressure. The problem is that by the time temperature hits the alarm level, you've already cracked the cylinder head or blown the gasket. By moving the alarms farther upstream in the cooling system you get more advanced warning and can shut down without permanent damage being done. Most of the newer Mercruiser engines with computer controls are alarmed on both raw water pressure and exhaust elbow temperature. My 7 year old Kohler generator is also setup the same way only with auto shutdown instead of an alarm. It is relatively easy and inexpensive to retro fit an older engine with an exhaust elbow alarm and it will go off almost instantly if cooling water is disrupted for some reason. I'll defer to the engineers who designed the alarm systems. I think we both agree that an audible alarm is the best way to get the helmsman's attention. Then he can look at gauges to determine what's wrong. |
#22
posted to rec.boats
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seagweed and cooling system
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#23
posted to rec.boats
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seagweed and cooling system
On Sat, 09 Jul 2011 23:37:12 -0400, Wayne B
wrote: The second is a temperature sensor/alarm at the exhaust elbow. Either or both of these give you enough warning time to shut down before damage occurs. Many modern engines have both. I have a glycol cooled engine, and and elbow sensor would warn long before the coolant began to boil at 250 plus. |
#24
posted to rec.boats
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seagweed and cooling system
"wf3h" wrote in message ...
On Sat, 9 Jul 2011 12:44:35 -0700 (PDT), Tim wrote: On Jul 9, 11:59 am, wf3h wrote: my 26' tolly has a freshwater cooling system. i put new water lines on last year so everything is in great shape. took it out last weekend in the fairway to practice docking. engine kept stalling at slow speed (600 rpm). got it back into the slip and found the bilge pump was running. opened the bilge and found the cooling water line from the throughull to the cooling water pump had completely collapsed even though it was wire reinforced. the end of the line had ripped away from the throughhull and water was streaming in. i shut the seacock and let the boat pump out put a new water line on, started the engine and it ran like a charm with no overheating. looking at the collapsed line...i remembered that the previous week the marina had filled with seaweed. some of this probably got stuck on the strainer and blocked the inlet.er before i put the new water line on, i backflushed the strainer with water and got good flow. but will keep an eye out for seaweed in the future. Bob, I dont know how course the strain3er is but I'[d think you'd see evidence of the sea weed stuck in the hose or the screen. Then again, i wouldn't think you'd gotten a bad hose but.... still a bummer! l saw bits and pieces of seaweed in the bilge..but backflushedl the strain so hope i got rid of it all...engiine seems to run OK so will replace impeller REPLY: You need to pull the end cap on the heat exchanger. That will be where little pieces of seaweed and Nemo will collect, cutting down on water flow. Is one weak point on Fresh water cooled engines. Little tubes, lots of little tubes that can plug. |
#25
posted to rec.boats
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seagweed and cooling system
On Mon, 11 Jul 2011 13:36:34 -0700, "Califbill"
wrote: "wf3h" wrote in message ... On Sat, 9 Jul 2011 12:44:35 -0700 (PDT), Tim wrote: Bob, I dont know how course the strain3er is but I'[d think you'd see evidence of the sea weed stuck in the hose or the screen. Then again, i wouldn't think you'd gotten a bad hose but.... still a bummer! l saw bits and pieces of seaweed in the bilge..but backflushedl the strain so hope i got rid of it all...engiine seems to run OK so will replace impeller REPLY: You need to pull the end cap on the heat exchanger. That will be where little pieces of seaweed and Nemo will collect, cutting down on water flow. Is one weak point on Fresh water cooled engines. Little tubes, lots of little tubes that can plug. good points...will check |
#26
posted to rec.boats
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seagweed and cooling system
wf3h wrote:
On Sat, 09 Jul 2011 23:02:18 -0400, L wrote: wf3h wrote: my 26' tolly has a freshwater cooling system. i put new water lines on last year so everything is in great shape. took it out last weekend in the fairway to practice docking. engine kept stalling at slow speed (600 rpm). got it back into the slip and found the bilge pump was running. opened the bilge and found the cooling water line from the throughull to the cooling water pump had completely collapsed even though it was wire reinforced. the end of the line had ripped away from the throughhull and water was streaming in. i shut the seacock and let the boat pump out put a new water line on, started the engine and it ran like a charm with no overheating. looking at the collapsed line...i remembered that the previous week the marina had filled with seaweed. some of this probably got stuck on the strainer and blocked the inlet. before i put the new water line on, i backflushed the strainer with water and got good flow. but will keep an eye out for seaweed in the future. If your intent was to prove you can't capitalize properly, you hit a home run. Other than that, blind man, what was the purpose of your post? this is a boating newsgroup, right? Thanks to your buddies, not really. Your lazy writing "style" makes you look dumber than you actually are. |
#27
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It's possible that seaweed plugged the strainer on the outside of the
hull (usually the through hull intake has either an integral strainer or a domed strainer cover. |
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