Strange heating issue

[miks15]

Morning All,

I recently had the engine out of my car (a 318i touring) and since putting it back in my heater hasn't been working properly.

When the car is stationary with the engine running i get some heat coming through the vents, its not mega hot but it is getting heat through. However when I am actually driving I only get cold air coming through. I thought it was maybe a bleed issue but then I don't understand why i get heat when stationary. Anyone had these issues before?

Thanks in advance!

[Tzantushka]

Heater core hoses round the wrong way?

[miks15]

Thanks, hadn't thought of that! Do you know which way round they are suppose to be? I can see I have one hose coming out the back of the head and one coming from under the inlet manifold.
I have found the following image online but it doesn't show which one goes where on the heater.

Capture2.PNG

[Brianmoooore]

Heater hoses almost certainly the wrong way around. The internal construction of the electric flow valve makes it act like a one way valve, shutting off the heater, when the flow rate increases with engine revs.
Hose from the back of the head goes to the lower bulkhead pipe.

[miks15]

Looks like we have a winner! Just checked my car and that hose is currently going to the upper bulkhead pipe!

Guess thats on the list of jobs... hopefully i can swap them both as they are without draining the coolant and too much mess!

Thanks for your help guys!