Jump to content
My Monterey
204FSX MIke

2012 204fsx mercury 4.3 alpha gen ii temp gauge

Recommended Posts

Just purchased this used 204fsx. 204 hrs. Runs amazing. Just noticed that the cooling temp gauge is not working. Worked the other day. What should I check? I’m pretty tech savvy so should be able to trouble shoot with your help. 
merc 4.3L is not getting hot. Exhaust is cool to the touch...  hope someone can shed some light. First step I’m thinking is to check the temp sender wire. But not sure where it is?  
thanks all. 
happy boating 

Share this post


Link to post
Share on other sites

Well the temp gauge drops to 100 degrees when running over 3000 Rpm. When I slow down and just cruise it pops back up to around 160 degrees.  Any idea what’s going on?

Share this post


Link to post
Share on other sites

I've got a similar problem so I'm following this thread.   My mechanic is going to hook up some analog gauges while I run to figure out what is going on.   Either a bad sensor or the raw water impeller is damage to where when you are running a idle it isn't spinning and providing cool water through the engine.      I get a solid alarm when it happens...

Share this post


Link to post
Share on other sites

When was the last time the impeller was changed? I had an impeller that was 2 years old and my temp gauge dropped to 120 no alarms. I have the 2000 Volvo 5.7 G??. I changed my impeller with a new Volvo unit and my temps returned to 158 - 160 and stays there at idle and 3000 - 3500 rpms. I've read the unit should be changed every 2 years.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...