rondds
Well-Known Member
- Oct 3, 2006
- 8,859
- Boat Info
- 2001 380DA
- Engines
- Merc 8.1s (2008)...Hurth ZF 63 V-drives...WB 7.0 BCGD (2013), Garmin 8208 & 740 MFDs, GMR 24xHD dome
Engine: 2007 Merc 8.1s, 314 hours
The past two times I had the boat out (two separate days), when coming off plane after running at cruise (~3400RPM), I got an alarm on the old style banner LCD SmartCraft display and on the Garmin MFD (connected to the engine PCM). Both displays basically say "Check Stbd Engine" (no help). Engine went into Guardian mode for several seconds and reverted to normal on it's own.
Each time this happened, the engine temps on the analog gauges were right at 170, the temps on the Garmin (MFD) were 176 first time, 168 second time. No interruption in water flow either time. First time I jumped in the ER as quickly as I could raise the hatch, with my wife running the boat at idle speed, with my handy-dandy IR temp gun and shot all normal readings (elbows, therm housing, manifolds, transmission, whatever I could (keep in mind, the alarm message was ambiguous so I didn't know exactly what I was looking for).
Connected the laptop to the starboard engine and ran the Diacom software after both of these occasions. Both times I got an OVERSPEED, a STBD EMCT OVRHT (exhaust manifold coolant temp overheat) and a PORT EMCT OVRHT. After the first incident, I did clear the codes from the ECM after the Sept 10 event, so the Sept 24 codes are new.
This explains what the code abbreviations stand for...
Mercruiser Alarm and Fault Codes
I won't bore you with the full reports, but in a nutshell, here's some pertinent results
Sept 10 alarm
Battery Volts - 13.52v
engine hours - 312.13
manifold air temp - 136.4
coolant temp - 176
engine speed 1026 rpm
Guardian Strategy - 23 seconds
Overspeed - 15 seconds
Sept 24 Alarm
Battery Volts - 14.3v
engine hours - 313.73
manifold air temp - 118.4
coolant temp - 168.80
engine speed 966 rpm
Guardian Strategy - 64 seconds
Overspeed - 8 seconds
I included the battery voltage in the above results b/c after doing some searching it seems it could be related to low voltage or alternator problems.
Note that the OVHT alarms, according to the Merc Code/Fault explanation, would require 212* to trigger (unless I'm reading that wrong).
There are sensors on the port manifold and on the starboard manifold. Interestingly, they read the exact same temp at the exact same time. Very unlikely both manifolds run at the same temp. But, again, the temps are not "alarming," though they triggered an alarm. Weird.
The ONLY temp readings that the report gives are the ones I listed above. ie: there are NO readings titled "EMCT TEMP" in the reports.
I did NOT have to shut down the engine to reset and get out of Guardian mode. Cleared itself.
Seems that OVERSPEED and EMCT OVRHT go hand in hand.
There was clearly no overspeed occurence since both times, this was coming out of normal cruise speed (not coming up on plane), and the rpm readings grabbed at the time of the alarm would indicate that there was actually no overspeed event.
Spoke to some bright people on this message board about it and the consensus was that these things happen to every engine but until the advent of ECMs and PCMs and and fault codes and smart-alarms, they've gone largely unnoticed. I'm not overly concerned about the issue, but, this engine could be trying to tell me something and getting an alarm when coming off plane each time is a PITA. Boat is going to bed very soon. I will likely just run the engines to heat up the oil for changing, and take a 4 min idle over to the travellift on the morning of Oct 7th.
Any ideas folks??
The past two times I had the boat out (two separate days), when coming off plane after running at cruise (~3400RPM), I got an alarm on the old style banner LCD SmartCraft display and on the Garmin MFD (connected to the engine PCM). Both displays basically say "Check Stbd Engine" (no help). Engine went into Guardian mode for several seconds and reverted to normal on it's own.
Each time this happened, the engine temps on the analog gauges were right at 170, the temps on the Garmin (MFD) were 176 first time, 168 second time. No interruption in water flow either time. First time I jumped in the ER as quickly as I could raise the hatch, with my wife running the boat at idle speed, with my handy-dandy IR temp gun and shot all normal readings (elbows, therm housing, manifolds, transmission, whatever I could (keep in mind, the alarm message was ambiguous so I didn't know exactly what I was looking for).
Connected the laptop to the starboard engine and ran the Diacom software after both of these occasions. Both times I got an OVERSPEED, a STBD EMCT OVRHT (exhaust manifold coolant temp overheat) and a PORT EMCT OVRHT. After the first incident, I did clear the codes from the ECM after the Sept 10 event, so the Sept 24 codes are new.
This explains what the code abbreviations stand for...
Mercruiser Alarm and Fault Codes
I won't bore you with the full reports, but in a nutshell, here's some pertinent results
Sept 10 alarm
Battery Volts - 13.52v
engine hours - 312.13
manifold air temp - 136.4
coolant temp - 176
engine speed 1026 rpm
Guardian Strategy - 23 seconds
Overspeed - 15 seconds
Sept 24 Alarm
Battery Volts - 14.3v
engine hours - 313.73
manifold air temp - 118.4
coolant temp - 168.80
engine speed 966 rpm
Guardian Strategy - 64 seconds
Overspeed - 8 seconds
I included the battery voltage in the above results b/c after doing some searching it seems it could be related to low voltage or alternator problems.
Note that the OVHT alarms, according to the Merc Code/Fault explanation, would require 212* to trigger (unless I'm reading that wrong).
There are sensors on the port manifold and on the starboard manifold. Interestingly, they read the exact same temp at the exact same time. Very unlikely both manifolds run at the same temp. But, again, the temps are not "alarming," though they triggered an alarm. Weird.
The ONLY temp readings that the report gives are the ones I listed above. ie: there are NO readings titled "EMCT TEMP" in the reports.
I did NOT have to shut down the engine to reset and get out of Guardian mode. Cleared itself.
Seems that OVERSPEED and EMCT OVRHT go hand in hand.
There was clearly no overspeed occurence since both times, this was coming out of normal cruise speed (not coming up on plane), and the rpm readings grabbed at the time of the alarm would indicate that there was actually no overspeed event.
Spoke to some bright people on this message board about it and the consensus was that these things happen to every engine but until the advent of ECMs and PCMs and and fault codes and smart-alarms, they've gone largely unnoticed. I'm not overly concerned about the issue, but, this engine could be trying to tell me something and getting an alarm when coming off plane each time is a PITA. Boat is going to bed very soon. I will likely just run the engines to heat up the oil for changing, and take a 4 min idle over to the travellift on the morning of Oct 7th.
Any ideas folks??
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