Question90 Chrysler New Yorker 3.3
This all started with the necessity to have all the vacuum lines replaced. Bought a new battery, followed the diagram and changed the hoses, changed PCV Valve air filter gave it a tune up (plugs wires) not sure if this is connected. The number 2 plug was "fouling out" so I got one of those extension things. It drove ok for awhile. Then, it started overheating. Still you drive it a few blocks in AZ heat and it started to wayy overheat! Had to stop let cool off then go for a few more blocks. Changed the thermostat but the one that came out was 180 degrees and the one we were sold wlas 192 (I think). When I drove it after that it still overheated in the same manner at the same speed. The radiator cap has one of those release knobs I thought it was a closed system and that the cap should not have that thing on it although the Auto Zone said it didn't matter they showed both caps could be used on that vehicle. Was told that the water was flowing corectly and that I needed to change the cap. Auto Zone again convinced me that it was probably the water pump. I just bought one but haven't put it on yet, I hurt my hand and don't know if I can do the job like this but when I checked the PCV valve it was not working. Theyp utit in backwards so I turned it around and drove it and it still overheated in the same manner as before. Should I just change the water pump? Could the radiator cap be the culprit? I'm at my wits end with this vehicle the Junk Yard is calling now!
AnswerI'll rule out a number of things for you real quick.
Unrelated:
Vacuum hoses
PCV valve
Plugs & Wires
Air filter
What could be related and symptoms:
Low coolant level. Always the first thing to be checked and will definitely cause overheating. Top off as required, only fill the coolant resevior to the area between the min and max mark.
Water Pump. Overheats in short distance. Frequently seen conditions include leakage from the Weap hole, bearing failure causing pulley to wobble, impellers break off, impellers to basically be sand-blasted away to nothing.
Bad Cap. Frequently a cause of "Lost" coolant and MOST of the time won't be a cause for actual over-heating. However, if you notice the cap has a pressure reading on it. That means it allows the coolant's boiling point to be raised considerably the higher the reading. This is not an excuse to buy a cap rated higher than what your system is designed to handle, just a heads up that you're basically raising the boiling point properly with the right cap for the job.
Thermostat. If installed backwards you've got no flow what so ever going in to the engine. The pointy part should be pointing up on the 3.3/3.8L engine on your vehicle. If you see the spring prior to putting on the filler neck I doubt it will fit but more importantly, it's not going to work.
Clogged radiator. It's possible for coolant to flow through a radiator that's partially clogged. The end result is that only a small portion of the radiator is used and ALL of the coolant is forced through that area. End result being is that the radiator does not absorb and shed that heat and hot antifreeze is dumped right back in to the engine thus no longer cooling it down.
Last but not least is the radiator fan(s). Your coolant fan(s) should come on with the a/c. If it doesn't, then there's part if not all of your problem. Stop and go traffic prevents enough airflow through the radiator to cool the antifreeze. This is where the cooling fan picks up the slack. No fan, no cooling.
I would recomend starting with checking the coolant fan operation. If they don't work check for power and ground. If both are present then you've got a bad fan or two. If you don't have power then check the fusible links (they look like wires) in the driver's strut tower area as well as those in the fuse block to see if any have burned out.
After the fans I would consider the radiator and the water pump equally and if you have access to one of those infra-red temperature probes you could see if the radiator is hot all the way across it's face. The water pump is not too hard to replace on your engine, just loosen the three 13mm head screws, pull off the belt, finish removing the 3 bolts, pull of the lower radiator hose (don't mess with the drain cock, they never work and frequently leak after attempting to use properly) to drain the antifreeze and pull out the 5-4 10mm head screws holding it in place.
Doug
