Our bmw z3 is over heating and we have put in a new termostat and pump but it has still not cured it. We have now got heater working but water seems to be blowing out

The heater core is blocked ! You can't have hot going in and cold coming out . The hot isn't going through ! How To Unclog Heater Core EricTheCarGuy

Try removing the termostat and run without.
if it cools Down you have Wrong termostat.
if not you have a blown headgasget.
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soren Halling,

Did you replace the water pump? BMW's pumps are **** because they have the plastic impellars. Get a metal impellar water pump an put it in. The car can't cool unless coolant is flowing. Hope this helps!

IF THERE IS STEAM THERE IS A LEAK AND IT IS HITTING THE EXHAUST AND THAT MAKES THE STEAM NO HEAT WOULD BE LOW ON COOLANT

You Might want to Check your Heater Control Valve,Its located under your Hood between 1 Heater Hose and your Water Pump.Its Vacum Operated and could be manual as well.Have someone turn your heat on and Off while you watch under the Hood at the Heater Control Valve to See if you see it Move.Or could have a Leak.More than Likely its Frozen Closed not allowing the Hot Water to Run Through Your Heater ore ,Which Results in No HOT AIR blowing inside. Try This 1st.

I would suspect that you pulled a wire off when you were installing the water pump. Check to see if you have spark

I too had similar problem when replacing the thermostat on my Z3. My advice is top up with more coolant and check the level.

hi jasso, I would recommend checking the water pump if you see no flow in the radiator. Make sure when you fill up the cooling system, that you fill it cold, and that the vent screw in the radiator is loose. fill system until fluid comes out the vent screw. tighten the screw, start the car and have someone run at 1500rpm and check for flow.also, make sure that you have your temp setting full hot and blower on middle speed so that you don't trap air in the heater core.

try changing your termostat

check and see if you get water/coolant circulates when you have the cap off (only check from cold start) the original water pump came with a plastic impeller and tends to strip on the shaft also check your thermostat before replacing water pump.