partial cooling system overhaul, temp issues and lower hose cold I'm hoping I can get some advice on this for a friend please. The car in question is a 96 318ti, with 67,000 miles. It was due for a coolant change, and also had signs that coolant had been leaking slowly from around the thermostat housing and the pipes that run to the heater core. Temperature gauge was reading low when driving, and reading just above the middle when in traffic. It used to always read right in the middle no matter what. The coolant was drained including the block drain plug, new thermostat & housing were fitted, and new pipes were fitted that link up the heater core. The bleed screw and (integrated) expansion tank cap were removed, heater set to max heat and fan set to low, and the car was filled with coolant, with the front end higher than the rear. it was filled until solid coolant started coming out the bleed screw hole, then the bleed screw and cap were refitted. The car was then bled again with the engine running, using a modified bleed screw with a hose that routes back into the expansion tank (to catch the ejected coolant). The radiator hoses were both soft at this point and were massaged to help remove some air from the system. It's been bled at least three times total during this repair now. Now the car seems to read a little hotter than usual on the temp gauge (just above middle), and the upper radiator hose gets hot and solid while the lower one stays cold and squeezable. When the engine is running with the bleed screw opened (modified bleed screw routing coolant back into the expansion tank, with a constant stream of coolant) and the expansion tank cap off, the lower radiator hose gets warm and the top hose was hot but still soft enough to squeeze. This doesn't seem normal that the lower hose should stay completely cold when the system is closed, but I could be wrong. Any advice or suggestions would be much appreciated. |