2002 QX4 Overheating (Radiator) - Stranded in Florida

[23cmcnitt23]

I started my long move to Colorado today and 300 miles into the trip my car started to overheat. I was able to cool it by turning on my heater and I got off on the next exit. My fluid levels were normal.

I stopped at the nearest mechanic (Micanopy, FL) and initially he said the fan clutch was the problem and needed to be replaced as well as the thermostat. The clutch was going to take 24 hours to get the part. The mechanic consulted with head mechanic and he felt the problem was likely only the thermostat, so we repaired it only. Long story short, I drove 5 miles and had the same problem. After reassessing the situation he determined that the radiator was likely clogged and needed to be replaced. He figured this out because one side was significantly hotter than the other side. Also, the fan was not spinning at it's appropriate speed. So he wants to replace the fan clutch (the original diagnosis).

So here I am stuck in a hotel in the middle of Florida trying to decide if replacing the radiator is the most appropriate thing to do? Should I try replacing the clutch first and see if that fixes the problem or just do both of them? I just want to make sure I'm not getting taken advantage of.

Thank you.

[qship96]

at almost 10 years old, replace both the radiator and clutch if both have never been done- I would even consider replacing the water pump if that is original and you plan on keeping the car for awhile longer.......all the above are typical jobs that need doing around the age of your car, and generally most cost effective and least downtime to owner to do as one complete job {along with both hoses and thermostat and belts} If all above is completed as one job, you now have another 10 years or so without any cooling system issues, provided you periodically flush the coolant.

[SteveTheTech]

I'd go radiator.

If the fan clutch fails it will fail in the engaged position meaning more likely than not. If you are driving on the highway when the car overheats that would indicate a clogged radiator most likely as insufficient heat transfer from restricted airflow or clogged passageways.

[23cmcnitt23]

Thank you both for the information. I ended up replacing both the radiator and fan clutch but not the water pump. I was able to make it to Colorado and thought everything was back to normal except for a loud fan (see below).

However, today it was raining and snowing in Colorado so I needed to use the heater in the car. Long story short, it doesn't work. It only gets hot when I accelerate, like on the highway. When I am sitting idle at a stop light it immediately starts to blow cold air and driving 35 mph it barely gets warm. When on the highway, it gets hot, almost too hot it seems. Also, since they installed the fan clutch, the fan is extremely loud, it's almost embarrassing how loud the fan gets when I accelerate from a stop light. I don't know if the two are related. I checked the coolant levels and they seem to be fine, maybe a little above the Max line. Any thoughts?

[mcrews]

Do you have the FSM???
It's linked here at nico.
It really is the bible.]
I have a 02 Q45 w/ 233k on it. I constantly refer to the manual for the exeact same type of questions. Really amazing how easy they are to use.
.........BECAUSE.......your curent problem is explained in the fsm.
I woulf bet that the mechanic didnt lossen the valve in back when filling the system back up. So there probalby is air in the syastem.

But if you go thru the check list in the fsm, it will pinpoint the problem.

and the fan problem is probably because the fluid level on the fan is too low......but I really can't be sure w/o checking the fsm.

[23cmcnitt23]

Thanks again for info. I went by my family mechanic today and there was a significant amount of air in the system. He used a vacuum device on the valve in the back to get the air out and it's working perfectly. It only took him 10 minutes and he didn't charge me anything. He said the fan will likely quiet down in time.
Thanks again

[CanuckQx4]

I woulf bet that the mechanic didnt lossen the valve in back when filling the system back up. So there probalby is air in the syastem.

.

Which valve are you speaking of? I believe I have air in my system (01qx4) and have similar symptoms as the op, maybe I am missing something in the bleeding process

[SteveTheTech]

maybe I am missing something in the bleeding process

There is a special tool many of us have to pull a vacuum on the cooling system. This isn't something you can DIY.

[hussain00]

Is this valve the same thing as the Air Flow plug as called out in the FSM? My 02 QX4 is heating up as well and i really think that it is because of a lot of air in the system... If we don't have this special tool, can we do something else? i remember reading in another post about raising the car to a certain level and just letting the car run? Thanks! Please read my entire story in the QX4 forum! I am desperate for help here as i don't have another way of commute!!

[SteveTheTech]

IMO- If you need it fixed right the first time you really might want to considering getting help.

If you have a radiator funnel you might be able to put some in there and try to rev the bubbles out, but the QX4 is notoriously difficult to bleed.

There is no five minute magic trick for this and if it is done wrong it will damage your engine eventually.

[CanuckQx4]

I really wish I would have gotten the correct air vacuum tool, they sent me the wrong kit and said they didnt have the right one in stock

Is that vacuum kit really THAT easy and a for sure way of getting out the air??