Over Heating - BMW Forum

dand65 · 08-01-2005, 05:16 PM

I have a 2003 3 series and it was overheating. The first thing I change was the thermostat. did not fix the problem. Some advice that I have recieved is that you must use the red coolant, does this make a difference. What other parts on the car can cause overheating. Thanks

storme · 08-01-2005, 05:36 PM

are all your belts in place,,,???? if one is missing this will overheat because the water pump isnt turning

did u put the thermostat in the right way round???
did you do a "reverse" flush of the rad??
did you bleed the system ??
is there a kinked pipe??
etc etc

dand65 · 08-02-2005, 01:43 PM

Quote:

Originally posted by storme@Aug 1 2005, 02:36 PM
are all your belts in place,,,???? if one is missing this will overheat because the water pump isnt turning

did u put the thermostat in the right way round???
did you do a "reverse" flush of the rad??
did you bleed the system ??
is there a kinked pipe??
etc etc

[snapback]366669[/snapback]

I never heard of a reverse flush. How is it done. Thank you for the info.

///M Power · 08-04-2005, 05:48 AM

Yeah i've never heard of reverse flush also.

Thermostat, Water Pump, Fan Clutch.

PIPES. Check your pipes!

schilke · 08-04-2005, 08:50 AM

You can buy at autozone a 'Flush Kit.' Basically its some fittings that let you tap into your heater core rubber hoses. The reverse part is when you flush the system thru the heater core OUTLET, thereby reversing the flow of water thru the system.

On such a new car, I don't think that is necessary.

When exactly, and under what conditions, is it overheating?

ON Highway = Water pump, thermostat
At Idle = fans not working, thermostat

schilke · 08-04-2005, 08:52 AM

Crap!

Forgot about the radiator cap or rather the expansion tank cap. BMW expansion tanks are under pressure and if the cap cannot hold the pressure an overheat may result -- highway or idle.

storme · 08-06-2005, 04:28 AM

A REVERSE FLUSH...............

your water in the radiator goes round in 1 direction...always....

so a reverse flush ,,is to flush the radiator and block by flushing,using a hose pipe. in the opporsite direction..

imagine the years of crud, all getting uded to going in the same direction...a flow pattern will appear,,,and all the crud will stick to it....
so if u reverse the flow,,it will take out most of the crud.....remember to remove the thermostat

when flushing...