Mitsubishi Repair: mitsubishi cooling, radiator hoses, stock radiator

Question
Hi Anthony

I have an Eclipse GST I just recently changed the radiator and thermostat because my car was overheating when in traffic. So I changed the thermostat and radiator. However when I got the radiator I didn't notice it was not the same as my stock radiator because it had like two holes on each side. I assumed they sent me an automatic eclipse radiator. So what I did was hook a hose that would be like just be another route for the radiator fluid to pass through. So regardless it's always flowing... there is a possibility that I need to put more radiator fluid in my car I think I was short when I was filling it in. however this was about a month ago. Now when I'm speeding about 70mph I noticed yesterday the temperature was going about normal. Can you help me out? Both radiator ( with that small detail ) and thermostat was changed. Can it be the radiator fluid? thanks Anthony


Answer
Rick,
I'm a little confused by your statement:
"Now when I'm speeding about 70mph I noticed yesterday the temperature was going about normal."  I'm going to assume you meant your temperature was going ABOVE normal.  Normal temperature should be indicated with your temperature gauge needle pointing about straight up.  Since you replaced your radiator and thermostat, you may also want to consider replacing your upper and lower radiator hoses, radiator cap, and the small water hose that feeds from your thermostat housing to your turbocharger.  Make sure your radiator fans are coming on as well when the engine reaches normal operating temperature.

The incorrect amount of coolant and improper water/anti-freeze mixture ratio can also lead to overheating.  Make sure there is no air bubbles in your cooling system.  Any Eclipse service manual (and general car maintenance web sites) can describe how to 'burp' your system to remove air bubbles.  Also, your coolant should be a 50/50 mixture of anti-freeze and water.  If all those are items are ok, it's possible your water pump is starting to fail.

I also recently replaced my radiator with an aftermarket radiator.  And my new radiator also came with those inlet/outlet nozzles for auto tranny cooling.  I did the same thing you did; connect the two with a piece of hose.  That is fine.  But that should not cause any over heating issues.  Check the items I've mentioned above and hopefully you'll be able to pinpoint and remedy your problem.
Good luck!