I have a '97 Audi A6 2.8L V12 with 67Thou miles on it that overheats w/in 10 mins. From the time I start the car. I had the radiator rodded and had flushed the engine. I also tested the block for any combustion leaks and found no leaks. No white smoke comes out from the tail pipe. I already changed the water pump, cleaned the hoses and removed the thermostat. I tried pressing continuously the radiator hose to bleed air out of the system. Inspite of all this, the overheating persists. Btw, the water temperature gauge and oil temp gauge are at normal levels. When the car starts to overheat, water starts to overflow from the closed expansion tank. There is no sign of oil in the water. Could it be that my water jackets are clogged?
Would appreciate any help on this. Thanks in advance.
Try bleeding it again using below procedures and BTW did you pressure test the R/Cap
BLEEDING COOLING SYSTEM
Always bleed air from cooling system after replacing coolant. Set heater for maximum heat. Remove radiator cap. Loosen drain plug and remove drain bolt (if equipped) from engine block. Drain coolant reservoir. Fill coolant reservoir to MAX mark with 50/50 water-coolant mixture. Loosen bleed bolt and fill radiator up to base of filler neck. Close bleed bolt when coolant flows out without bubbles. Tighten bleed bolt. With radiator cap removed, start and operate engine to normal operating temperature. Add coolant if necessary and check for leaks.
You see were nice people well here it is go apply it