Agreedbiggie wrote:Seems like bad water pump.
You know, I was going to bleed the system in my 240 the other day following your instructions, but I couldn't.. All I had was Dr. Pepper bottles.. Sucky!OutToWinPAHC wrote: Take a 2 liter pepsi bottle cut it in half and use some black electrical tape and wrap the bottle neck a little
G_U_knit wrote:So, I put back the old T-stat back on the car, after I verified it opened and closed at the right temps(did it on the stove with thermometer). Burped the coolant system...followed instructions given. No more bubbles showed up. Changed Oil for the car and took it for drive, making sure nothing was leaking. Everything works great...including the car not overheating now! I took the car several times up to high RPMs, then drove it for over 100miles this weekend, The temp gauge doesn't even budge after the car warms up. I'm glad this is the case, but don't understand what has changed that world have stopped the car from overheating. Anyone got any thoughts on this. Thanks again for everyones help on this.
Hit the nail on the head. I have an 04 G35 Sedan RWD and I have had a b**** of a time to get it to stop overheating. Here's what I did: New radiator (cheap $50 on amazon), new double cooling fans (cheap $80 on amazon), new Autozone thermostat. New belts, pulleys and hoses. I flushed the radiator probably 6 or 7 times this weekend. I used water, water with white vinegar, water with CLR (calcium, lime, rust in gray bottle). Flushed a LOT of crap out. I took the entire front end off to do all this. I even blew the whole cooling system out with 100+ psi using my big air compressor. Put everything back together, added coolant, kept overheating. You NEED to get the front of the car as high of the ground as possible. My front tires are 6" off the deck. Do exactly what Out To Win says but ALSO: with the radiator cap off and a big funnel in there to collect the fluid so it doesn't s*** everywhere, get the car up to normal operating temp and you HAVE TO rev it to 6 or 7K RPM's a few times to really clear any blockages and really get the coolant circulating through the system with a lot of quick high pressure. Keep burping it, keep letting steam out of the bleed screw back by the firewall until liquid starts coming out and then tighten it back up. Also, make certain your overflow reservoir is at least at the Max line with coolant or water. Right now I've got Prestone 50/50 and a full bottle of Water Wetter ($10 at Auto Zone) and as I'm typing this, the car has been idling in my garage up on the jack stands still for 31 minutes straight and the temp gauge is sitting perfectly where it should be and isn't fluctuating at all. I'm very happy and I HOPE this helps someone who googles this problem and finds this thread. It's a pain in the a** to get the Air out of these cooling systems on the G35/350Z and you start thinking, what if I have a blown head gasket? What if my thermostat is bad (even though you just replaced it)? What if my water pump is bad? That's the kind of s*** that starts going through your mind and might cause you to do unnecessary maintenance or worse, take it to a dealership or a mechanic and get bent the f*** over. I was getting extremely frustrated cuz I just couldn't figure out why it wouldn't stop overheating and I'm actually a pretty good mechanic. Keep repeating the steps and take my advice about hitting the rev limiter pretty much and hopefully it'll work for you like it worked for me!OutToWinPAHC wrote:Check radiator cap (store can do it)
Pressure test the system at 1.3 bar for 30 min or more, you can get a coolant system pressure tester through loan a tool. Fix any external leaks, you can usually hear them.
Then bleed it.
Jack the front of the car up front tires off the ground 4-6 inches.
Take off radiator cap
Take a 2 liter pepsi bottle cut it in half and use some black electrical tape and wrap the bottle neck a little, or get a cooling funnel
Flip it around and place the bottle neck were the radiator cap was at. Pinch off over flow line if not using the funnel.
Now start filling it with coolant about half way
Remove bleeder screw
Close bleed screw after you get a nice even stream of coolant
Squeeze the upper, and lower lined and burp out the air
Add antifreeze until you over fill the rad by a quart
Turn the heat on full blast
Start the engine and let the engine run after 3-10 minutes the thermostat will open and suck in the excess antifreeze (ambient temp affects time)
Fill it again but with about a half of quart.
Let it run until no more bubbles come out. Squeeze hosed time to time.
Replace cap, unclamp overflow hose and then shut off the engine, fill over flow 1/2 to 3/4
Coolant funnel (best to have)