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· Registered
12 Posts
Discussion Starter · #1 ·
What's up guys?
O.K here's the situation

i have a 2004 745I with 90k miles.

over the weekend I changed my water pump, thermostat, and coolant, and now my car is running hot.
While driving to work this morning I was running at 108C (228F) with the outside temp being about 12C (52F). If i remember correctly before the water pump change I was running about 96C.
Air in the system?

I flushed all the water from the radiator and the engine block, but I was only able to get about 11 liters of coolant back in out of the 14 liter capacity my engine takes.
This is how I refilled the coolant:

before re-filling coolant I turned ignition on (engine off) set blower level to low, heater temp to max, and started filling overflow tank. When the coolant reached Min in expansion tank I started the car (BLOWER LEVEL high, HEATER TEMP TO MAX), and ran her for a minute or so then closed the overflow tank.

Did I miss Something?
Does anybody know how hot these engines run?
could it be the other t-stat located on the radiator (#16 here):dunno BMW E65 745i MOUNTING PARTS F RADIATOR


· 42, The meaning of life
2,397 Posts
There is a bleed valve at the top of the radiator shroud just left of the expansion bottle (towards centre of the car), you can bleed excess air via that point. One way to get more fluid into an empty cooling system is (when cold) to take the top radiator hose off, and pour coolant into the hose to fill the block, and then into the radiator as well.
Another trap is the thin hose that runs between the radiator and the expansion bottle, if that is kinked or pinched, it won't let any trapped air purge off to the expansion bottle.

Good luck. Let us know if it helps
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