2007 8.1 alarm issues. HELP PLEASE

Have some issues with the motor going into guardian mode. Had the dealer do a scan and said manafolds were getting warm. 130 total hours on motor. salt water use. Do you need to reset it or does it reset automatically?

Suggested to do the waterpump first and then maybe manafolds. I changed the thermostasts first. No change. Then changed the impeller and the pump housing. No Change. I think I'm going to change the temp sensors next. Question is, what is inside the manafolds that can go wrong? Are there water passages in there that can corrode and cause issues. should I consider doing the manafolds?. Motor runs at about 170 degrees before alarm Goes off. I only have couple weeks left to get this done this season and would like to figure it out before winterizing. Once you let it cool for a minute at idle you will get full throttle back.
This is a closed cooling system.

with closed cooling 170 is normal .Try using a laser temp gauge or try replacing the water pressure sensor http://www.ebay.com/itm/Water-Press...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Bt Doctur said:

with closed cooling 170 is normal .Try using a laser temp gauge or try replacing the water pressure sensor http://www.ebay.com/itm/Water-Press...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Click to expand...

Ya it's always run at that temp. Where is the water pressure sensor located?
going to change both sensors in the manafolds too. Are there any other temp related sensors?

either on the power steering cooler or at the raw water pump, let me find the link

another version in Blue http://www.pleasurecraft.com/manuals/L510003.pdf

Manual 30 can be burned also

Thank you
great info

What is manual 30?

can the temp sensors be bypassed or jumped
for test purposes

30 looks like the mercruiser manual for your motor, You should be able to fool the computer with resistors but I`m still working on the procedure and the values for the sensors

Bt Doctur said:

30 looks like the mercruiser manual for your motor, You should be able to fool the computer with resistors but I`m still working on the procedure and the values for the sensors

Click to expand...

Going to change the exhaust manafolds and both sensors. Also the pressure sensor as you suggest. Where can I get a manual 30?

OK really starting to get frustrated. I changed the water pump housing and impeller. Also the 2 manafolds, both manafold temp sensors and the pressure sensor. Motor does not overheat. Alarm still goes off just over 3000 rpm. I back the throttle off and it goes off. I took the 2 old sensors and plugged them in and put them in a cup of water. still the same thing. Now thinking this is not a water issue. I also changed the thermostat and oil and filter. oil pressure is about 41 . Whet else can make the alarm go off. This is starting to suck and is getting expensive. motor has 130 hours on it. Elbows are stainless steel and look in mint condition Ser# on motor is 0w335279 Also changed the fuel filter and remote water separator.