I recently purchased my first boat. It has a 2002 90 hp Yamaha two stroke and it's mounted on a 2002 172 Scout Sportfish. I love everything about the boat and set up.
Recently, when in idle or less than 10,000 rpms for longer than a few moments, the overheating alarm is going off. At first I checked the intake and the "pee" hole, and the intake seemed fine and the "pee" hole had strong water coming out. I contacted my local boat guy, and we took out the thermostat poured some toilet bowl cleaner and let it clean out the system and then washed through with clean water for several minutes. I then replaced the thermostat with a new one.
When I got back out on the water, the first 20 minute ride in a no wake zone was fine. The next time out, when I first was in the water the alarm started after a few minutes of idle/no wake zone. But once I started going about 15,000 rpm it went off. Then yesterday after I sat the boat on an island for a couple of hours, when I idle away from the island the alarm started. Again when I started to give some gas, it subsided.
It appears that once I get out of the no wake zones and start going faster, the Alarm subsides. Any suggestions on what might be going on. I apologize as my boat knowledge is somewhat limited.
Thank you in advance for your help.
Recently, when in idle or less than 10,000 rpms for longer than a few moments, the overheating alarm is going off. At first I checked the intake and the "pee" hole, and the intake seemed fine and the "pee" hole had strong water coming out. I contacted my local boat guy, and we took out the thermostat poured some toilet bowl cleaner and let it clean out the system and then washed through with clean water for several minutes. I then replaced the thermostat with a new one.
When I got back out on the water, the first 20 minute ride in a no wake zone was fine. The next time out, when I first was in the water the alarm started after a few minutes of idle/no wake zone. But once I started going about 15,000 rpm it went off. Then yesterday after I sat the boat on an island for a couple of hours, when I idle away from the island the alarm started. Again when I started to give some gas, it subsided.
It appears that once I get out of the no wake zones and start going faster, the Alarm subsides. Any suggestions on what might be going on. I apologize as my boat knowledge is somewhat limited.
Thank you in advance for your help.