temp rises when A/C is on

[usar89b]

My 89 240 runs fine with the A/C off, but tries to overheat when I turn it on to cool down. The electric fan in front of the radiator kicks on but the temp still rises. I have to shut down the A/C until the needle on the gauge goes back down to normal. Could anyone help me please? With a few ideas, I'm sure I can narrow down the problem and solve it.
Thanks

[nissan_240sx]

yea I was gonna say the fan may not be turning on. Notice anything happening as the temp rises? over flow tank flowing? bubbling?
Anyone else wanna chime in

[usar89b]

Went outside this morning and noticed coolant puddle underneath car. Got flashlight and traced it to water pump. If the temp is fine without the A/C on, does it sound like I need a new water pump, or just install new gasket?

[usar89b]

I went ahead and bought a new thermostat and plan to install it along with removing the water pump to inspect and reinstall with new gasket and sealer. If this doesn't fix the problem, then i will continue to replace the coolant system components until the problem is solved.

nissan_240sx thanks for replying. You live on a beautiful island. I saw your car pics in the other thread and noticed the license plates. I spent two months there in 1994 and loved every minute of it.

[nissan_240sx]

Cool, hope your problem gets fixed

Thanks usar89b! Guam is a beautiful place =)

[rollhard]

If you havent changed your water pump already, I recommend you do it. I generally change the water pumps on my cars every 60-70k miles to prevent the very same problem you are having right now. Thermostats dont really leak, they usually get "stuck". Your problem sounds like a water pump problem. The parts in the pump are worn down and will not pump and flow the needed amount to cool the engine while the AC is on. I would also get the engine tested to make sure you dont have a blown head gasket.

Also...check the fans. Just because it turns on, doesnt mean its blowing to its full potential.

[usar89b]

thanks rollhard for the advice. It just so happens that I bought a new waterpump today. I plan to install it along with the thermostat in the morning. I've already changed the oil to see if there was any coolant fluid mixed in and there wasn't, but I'm keeping an eye on the head gasket scenario, I realize that could be a problem as well. Also, a friend of mine in the Army Reserve told me to check the fan clutch. Thanks again guys...

[usar89b]

Replaced water pump, thermostat, hoses and belts...problem solved. Haven't had any problems for three days!

[nissan_240sx]

Solid!

[DC1984]

thats what i had to do with my 240 when i first bought it. the water pump ppropeller was completly gone and ther was nothing left of the thermostat but the little O ring that seals it.