Hi all.
Have a single KAD300 hooked to a DP-G drive in a 2005 planning hull cruiser.
Engine was at 609 hours when the problem arose (and now 617), clean bottom, drive, props, impeller changed last year and did 95 hours, heat exchanger, oil cooler, power steering cooler and aftercooler cleaned 3 years/280 hours ago also turbo and compressor.
Last summer while cruising on a cross/beam sea on plane jumped over a wave and suddenly overtemp alarm went off, also the overtemp indicator flashed on the alarm panel, temp gauge showed 100C. Immediately pulled back the throttle to neutral and temp decreased to 85C then hit the throttle but engine revs limited to 2200. This must be caused by stern drive water intake became out of water and suck air instead of water.
Stopped and restarted and engine ran without over temp. 15 days later from this incident same happened again since I jumped over a beam sea wave. Checked the impeller and it was fine. Also I'm a year round boater and have never had an issue like this until one month ago.
I run on plane at 3000rpm reaching 18,5-19 knots, trim tabs fully retracted and drive trim -2 to +2 according to sea and load conditions.
One month ago while on plane cruising around an island where I spend my summers on a glass water, turned to port 30 degrees via autopilot and overtemp alarm went off BUT temp gauge was at 85C (which is the degree of 1st thermostat and at 92C 2nd thermostat opens) pulled back the throttle jumped in to the bilge and checked the seawater components/hoses buy IR temp gun and there is no real overheating also outdrive was intaking and discharging water and touched to impeller housing was cold.. Hit the throttle and couldn't pass 2200rpm. Stopped and restarted then no problem.
This fake overtemp problem arised last five consecutive days where I was on the boat, alarm wents off after a few minutes of getting on plane on a wavy day, and once happened at the marina entrance to pass the other boats I hit to 3500rpm and then happened while I was cruising 20 minutes problem free. Yesterday I uninstalled the impeller and it was spotless and installed it back.
Also I added approximately 1 liter freshwater to the coolant expansion tank where I filled fully antifreeze, and it's spread into the bilge so antifreeze level was/is correct .
Ran the boat a few days later 15-20 minutes on plane in a half meter chop/wave at 3000rpm north and south, cross and beam sea and haven't the overtemp alarm went off.
Before the trip I did my regular daily/weekly maintenance such as checking the acidity level of the wet cell batteries, toping off the electrolyte, measuring with multimeter batteries, battery cables, alternator and starter both engine on and off, draining the racor diesel/water separator and purging the fuel system. All were fine but I checked them since I'm thinking that I have an electrical problem and if my batteries are defective and cause but they are fine/2year old.
Also before the trip I sprayed liberal amount of Boe T9 to the all electrical components/sensors on the engine, back of temp gauge and alarm panel cables as if they are corroded and causing false/fake overtemp alarm
Next day I ran the boat on plane at 3000rpm half an hour (15 minutes and a few hours later return trip 15 minutes), boat ran great seas were flat at first ride but were choppy at the return trip, had no alarms.
I'm thinking that if spraying T9 did some magic and sorted the problem, or jumping over the waves caused the two or least second 92C thermostat stuck closed and coolant was not cooled by the heat exhanger/sea water.
Also I tightened the on engine sea water filter cap tightly if air is escaping and causing less sea water to circulate but there is no signs of leaking water around the filter.
The alarm arises sometimes as engine couln't pass 2900rpm (where my planing threshold is 3000rpm) than a few minutes later overtemp alarm wents off but again there isn't real overheating.
Would a defective turbo or boost pressure sensor cause the engine to give overtemp alarm if the engine can't produce more rpms than 2900 ?
Talked to my mech and he thinks this is not a mechanical issue and would be electrical and he'll be onboard today to hook vodia . I'm guessing that while jumped over the waves the temp sensor in the exhaust elbow loosen or moved a bit or broke etc and cause false alarm then pretends the engine as there is real overtemp.
Also EDC control panel D button gives 1.1 code which means there is no problem, but I wonder if really an overtemp occurs will it show a trouble code or if I'm having an electrical problem shouldn't it blink different from 1.1?
Hope someone can shed some light to my problem.
Thanks in advance.
Have a single KAD300 hooked to a DP-G drive in a 2005 planning hull cruiser.
Engine was at 609 hours when the problem arose (and now 617), clean bottom, drive, props, impeller changed last year and did 95 hours, heat exchanger, oil cooler, power steering cooler and aftercooler cleaned 3 years/280 hours ago also turbo and compressor.
Last summer while cruising on a cross/beam sea on plane jumped over a wave and suddenly overtemp alarm went off, also the overtemp indicator flashed on the alarm panel, temp gauge showed 100C. Immediately pulled back the throttle to neutral and temp decreased to 85C then hit the throttle but engine revs limited to 2200. This must be caused by stern drive water intake became out of water and suck air instead of water.
Stopped and restarted and engine ran without over temp. 15 days later from this incident same happened again since I jumped over a beam sea wave. Checked the impeller and it was fine. Also I'm a year round boater and have never had an issue like this until one month ago.
I run on plane at 3000rpm reaching 18,5-19 knots, trim tabs fully retracted and drive trim -2 to +2 according to sea and load conditions.
One month ago while on plane cruising around an island where I spend my summers on a glass water, turned to port 30 degrees via autopilot and overtemp alarm went off BUT temp gauge was at 85C (which is the degree of 1st thermostat and at 92C 2nd thermostat opens) pulled back the throttle jumped in to the bilge and checked the seawater components/hoses buy IR temp gun and there is no real overheating also outdrive was intaking and discharging water and touched to impeller housing was cold.. Hit the throttle and couldn't pass 2200rpm. Stopped and restarted then no problem.
This fake overtemp problem arised last five consecutive days where I was on the boat, alarm wents off after a few minutes of getting on plane on a wavy day, and once happened at the marina entrance to pass the other boats I hit to 3500rpm and then happened while I was cruising 20 minutes problem free. Yesterday I uninstalled the impeller and it was spotless and installed it back.
Also I added approximately 1 liter freshwater to the coolant expansion tank where I filled fully antifreeze, and it's spread into the bilge so antifreeze level was/is correct .
Ran the boat a few days later 15-20 minutes on plane in a half meter chop/wave at 3000rpm north and south, cross and beam sea and haven't the overtemp alarm went off.
Before the trip I did my regular daily/weekly maintenance such as checking the acidity level of the wet cell batteries, toping off the electrolyte, measuring with multimeter batteries, battery cables, alternator and starter both engine on and off, draining the racor diesel/water separator and purging the fuel system. All were fine but I checked them since I'm thinking that I have an electrical problem and if my batteries are defective and cause but they are fine/2year old.
Also before the trip I sprayed liberal amount of Boe T9 to the all electrical components/sensors on the engine, back of temp gauge and alarm panel cables as if they are corroded and causing false/fake overtemp alarm
Next day I ran the boat on plane at 3000rpm half an hour (15 minutes and a few hours later return trip 15 minutes), boat ran great seas were flat at first ride but were choppy at the return trip, had no alarms.
I'm thinking that if spraying T9 did some magic and sorted the problem, or jumping over the waves caused the two or least second 92C thermostat stuck closed and coolant was not cooled by the heat exhanger/sea water.
Also I tightened the on engine sea water filter cap tightly if air is escaping and causing less sea water to circulate but there is no signs of leaking water around the filter.
The alarm arises sometimes as engine couln't pass 2900rpm (where my planing threshold is 3000rpm) than a few minutes later overtemp alarm wents off but again there isn't real overheating.
Would a defective turbo or boost pressure sensor cause the engine to give overtemp alarm if the engine can't produce more rpms than 2900 ?
Talked to my mech and he thinks this is not a mechanical issue and would be electrical and he'll be onboard today to hook vodia . I'm guessing that while jumped over the waves the temp sensor in the exhaust elbow loosen or moved a bit or broke etc and cause false alarm then pretends the engine as there is real overtemp.
Also EDC control panel D button gives 1.1 code which means there is no problem, but I wonder if really an overtemp occurs will it show a trouble code or if I'm having an electrical problem shouldn't it blink different from 1.1?
Hope someone can shed some light to my problem.
Thanks in advance.
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