Do you notice small air bubbles in the coolant recovery tank when you first start the engine, this would indicate a possible blown head gasket, and these are known for doing just that. If not then these things can be a real bear getting the air out, I start by filling the radiator through the upper hose on the engine side, when it takes all it can quickly shove it back on and tighten the clamp, then fill the recovery tank and raise the passenger side at least 6 inches, a car ramp is just right, start the engine and keep adding fluid as it takes it, when it stops taking fluid put the cap on and shut it off and wait 15 minutes, then check level in the recovery tank, if low carefully remove the cap as there might be pressure there, if there is too much pressure wait a while longer, when pressure drops enough for safe removal, top off the system and restart watch the level as the engine warms up, if it threatens to run out of the tank reinstall the cap and let the engine continue to run until the thermostat opens, and that should take care of any air pockets. Then make sure the cooling fans operate properly.
There is hope for your NORTHSTAR ENGINE if it overheats and has blown head gaskets. I spent 5 months researching the problem and finally found Norm Huhn who manufactures the inserts needed to fix the aluminum heads and keep them attached to the steel engine block. After I finally figured out what the problem was on my wife's 2000 Cadillac Sedan Deville, and after wasting my money on what's called the TRIPLE PLAY, (replacing the water pump, the thermostat, and the crossover upper gaskets) coupled with the use of a liquid sealer (which never works) my mechanic told me not to throw any more money into this car. Hogwash, since in my heart, I knew that was the proper way to fix the problem and a good mechanic somewhere out here who knows how to do the job right. Even my own local Cadillac Service Manager was in denial about this engine's inherent manufacturing problem from 1999 through 2003. Norm gave me 3 good leads, all within 30 miles of where I live, and I chose the one guy who had no-call-backs on any of his Northstar Head Gasket repairs. YES, it is a lot of work! A full day to remove the engine from the bottom of the car, a full day to break the engine down and drill out the 20 new slots for the Huhn inserts, replace the gaskets, and torque the new bolts, and another full day to reinstall the engine. The fix turned out to be a steal at $3K since where would we be able to get a Cream Puff 2000 Cadillac Sedan Deville with only 68,000 miles on it for that amount of money, or for that matter, and other good reliable used car? As it turned out, our car also needed new front brake pads, 2 new front rotors, a new power steering pump, a new starter, and a new E-Brake release contact, which my wife and I were well aware of. The same EXPERT Cadillac Mechanic charged us another $1K to do all those repairs too. And now, my wife's Cadillac runs just like it did when she drove if off the dealer's lot 17 years ago. You can contact Norm at his website, http://www.huhnsolutions.com/ And you can reach me at email@example.com for additional info if you live in the tri-state region of NY, NJ, or CT.
I have a 2000 Deville that's been over heating like crazy. I've changed the thermostat and the housing, the water pump and it's housing,, the radiator the upper and lower hoses it still was over heating did the block test and headgasket test all was good. I did noticed no one never talks about that coolent temperature sensor that can also cause over heating. I just changed that which goes along with the coolent system that Ppl over look that is very important and can cause a car to over heat. My dash yeastday read it was over heating but the engine was fine. No bubbling out the resorvor. Maybe it's the computer. Today it hasn't overheated yet. I've changed all that needed to be changed and I'm just puzzled what else could it be... Oyeah I unplugged the battery cleared the codes so the car can reboot plugged battery back up to reset everything and see what happens. Oyeah I cleaned the lines from the tank to the block going across the intake up top. Somebody let me know what you think. Thanks
I also forgot to mention the heat is blowing cold now. I haven't flushed the heater core yet but would that cause the heat to blow cold? I know a little something that I've learned since owning my 00 Deville I've had this car going on 6yrs. I never had any major issues till now with it. This Northstar is dangerous when it starts getting ill!
Joe near CHGO, auto mechanic, does gaskets on Cadi's real cheap. People come from surrounding states for him to fix them. Call him 847-776-7633.
Why is my 2000 DeVille overheating when I drive about 10 minutes
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