Merc blackmax 150hp high temp alarm

[endebt]

"1995 blackmax 150hp high temp

"1995 blackmax 150hp high temp alarm comes on after 22 minutes of run time over 4000 rpm. changed impeller, thermostats, popit and flushed, mech checked head gasket,exhuast gasket. still comes on after 4000 rpm. what am i missing"

 

[Chris1956]

"Eric, You need to remove the

"Eric, You need to remove the hi temp sender and test it in a pot of hot water, with a meat or candy thermometer. Put an ohm meter on it and when it reaches 180+ degrees the resistance should drop to none."

 

[endebt]

"Chris, one thing I forgot to

"Chris, one thing I forgot to mention was that, we took a heat gun and noticed that the port side of the motor was 20 degrees hotter then starboard. I will have to get an ohm meter but I will try this out because right now I do not know whats going on. If this does not work at the 180 degrees, then this may be my problem? have you ever had this happen before?"

 

[galamb]

"Eric, these sensors are of a

"Eric, these sensors are of a simple design and do fail quite often...

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