[THEFERMANATOR]

Originally Posted by draglink

My 2.4 tends to run warm. It will overheat with T-stats in...I've run with out for years. BUT if yours runs normal temp with T-stats then def put them in as Destroyer said

On some mERCS taking teh t-stats out can burn one up in a hurry. The poppit valve assembly must be working for the cooling system to work, otherwise the stats can't work. And that impeller is done. The impeller vanes need to stick straight out as that is how they work. These pumps are a displacement design where the impeller fins move in and out to compress the water out and pull the water in. Once the impeller vanes get laid over like the ones pictured, it is no longer pumping much. This is most important at high RPM's as the vanes need to move in and out rapidly. And the MERC impellers are a tall but short vaned design as they are a high pressure design meant for MERCRY's poppit controlled cooling system whereas other engine manufacturers used a high volume design with longer impeller vanes that aren't as tall.