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Did you ever find out this information paul? I have a 2005 bf150 with some temperature problems and I would certainly like to know this information.Of the 4 Temp Sensors
Cylinder Head
Cylinder Block
Exhaust
Engine Case
What temps trigger the ECM to alarm? Which one causes the ECM to Alarm and subsequent shutdown motor?
I am monitoring each with A/D converter into a computer.
Paul
Nobody has responded that I've seen yet with that information. I'm doing some separate investigation trying to figure out how all this works. Since we probably have the same outboard motors it sounds like a good idea to be in closer communication. How do we go about sending private messages on this site?Did you ever find out this information paul? I have a 2005 bf150 with some temperature problems and I would certainly like to know this information.
EBT is block temp and that is the temp reading you get on the NMEA network and it is definitely montored by the ecu.and is triggered at 110 deg C
Bottom-line
Tested both engines with Dr H and Thermocouples in exhaust water output and water output from combined Cylinder Head/Block. In around 155F reading from thermocouple and Dr H reports 158F
Engine alarms and subsequently shuts down. So, both engines computers are responding the same just that Starboard engine gets to 160F faster than the Port Engine.
So, I guess I could try faking engine say 10F such that it may extend shutdown point but increases overall head temp.
Here's my take on that: the thermostats for the head and block remain closed or partially closed from below 140° F to about 160°f ...this ensures that the engine will not be running cold and lets it heat up quickly. Above 160°. The thermostats then have basically no further impact on the temperature regulation.. they can't open up anymore than they are. I can imagine that the engine will tend to generate more heat at higher RPMs, but this is kept in check by the impeller pushing much more water into the engine as the RPMs increase.That's correct, I just haven't worked out how they achieve 90 plus in the block with a 60 deg thermostat, but they do