496Ho Code help
 

Was out this past weekend. Ran the boat at about 4000.
When I came off speed to idle alarm sounded. I have a system view but just gives the basics. Codes, RPMs, oil press. DOes not read MPH or give GPS. PRevious owner added the system.
It did display guardian mode stbrd engine. I check code history. It displayed four codes.
Code 19- over speed
Code 160
Code 179
Code 9
I plugged these numbers into my phone note pad.
The sys view did a brief disc. Dont remember though.
Somthing about over heat temp ECT maybe

Temp of both engines was at 160-170. Oil press good.
Turned off key and restarted Guardian went off and boat drove the rest of the day fine.
Any help with these codes? Some items to check?

Thanks
Dennis

Code 19 - Overspeed
Code 160 - Port EMCT Overheat
Code 179 - Starboard EMCT Overheat
Code 9 - Gaurdian Strategy

Looks like you had a reduction in seawater flow for some reason.

Thanks Dave for the reply.
Can you help with another question.
What is the normal water pressure of a 496 engine?

One of my engines reads about double the other.
Eg Port engine reads 10psi stbrd reads 20psi

Merc says;
1-5 PSI at idle
7-17 PSI at WOT
The older 496's that have the sensor on the seawater pump will run a little higher than the newer power steering cooler mounted sensors.

Thanks Looks like I'm due for both engine sea impellor replacments.