Overheating Infinity I30/Maxima

DEBLOG

MEMBER
1930 NISSAN MAXIMA

I have a 1998 Infinity I30 with 65,000. Somewhat same as Maxima, engine at least. Recently it has almost overheated twice after being on the road for about an hour. Both were in hilly areas with stress being put on the engine. Turning off A/C solved problem, heat gauge went down quickly. It does not overheat while idling at stop light or on short trips. Checked fans and thermostat and all fine and working properly. What could it be? Water Pump? Any help is appreciated. Thanks

2 Replies

MIKEYBDMAN

MECHANIC
623 POSTS

You said you checked your fans and thermostat. I understand seeing if the fans are running is a great check. But how did you check your thermostat? Replacement is a great check, and a rather cheap preventative maintenance. If you have not done so, I would replace the thermostat. Theres not much to go wrong with a water pump. Usually they are replaced when they leak. I could see if your system had never been taken care of, maybe the impeller is all rusted up and not being efficent. You can replace your pump if you desire, but you will probably find the one you take off is pretty close to the one you put on. Again it is not a hard thing to replace, and relativley cheap.
If your thermostat is getting old, and starting to stick little, I could see this being a little problem. Also if the thermostat sticks open, the fluid may pass thru the radiator too fast to cool it enuff for when your car is under a load.
Check the fins on your radiator/condensor and see if you are getting good air flow across the radiator coils. They make flush kits to back flush your radiator and try and clean it out in reverse. It might not be a bad idea to replace the thermostat and flush your radiator and see if that will get your system back to handling the load under extreme conditions.