It might be the aux water pump which is mounted on the heater valves.
Hi,
I just cant get any heat from my 89 525iA M20. I've reconditioned the heater control valves (thanks to all the excellent info on this board) and am pretty sure they are working ok. I can hear them "ticking" and with the engine warm the two output hoses are hot as is the output hose from the firewall.
I'm certain both the cores are getting hot because all the hoses get hot as I mentioned and it's possible to get just a tiny amount of heat from the windscreen vents when the engine is really up to temp.
No matther what all I get is cold air (theres no A/C in my car) through the vents.
What I'm thinking is that none of the air is being drawn through the cores. Is there a flap or something that directs the air?
The fan blower switch doesnt work properly either, but I'm treating this is a seperate problem (the fan speed doesnt control the heat only the fan speed, right?)
Why would I get no heat inside the car when the cores are getting hot?
I'm really stuck now!
It might be the aux water pump which is mounted on the heater valves.
Originally Posted by Scott E
Hi, thanks for the reply. Sorry I should have mentioned that the car doesn't have the extra pump.
euro cars i've not seen excluded, all e34/e32s have the pump, it's well hidden under the valves, its not a option it's needed to push water through the extensive amount of tubing and the dual heater core, ill post a pic of where it is afterwhile
all america wants is cold beer warm cat and a place to take a poop with a door on it
Its a UK car. Almost certain no pump - if there is its not anywhere near the valves.
Here is the a picture of the aux waterpump detached from the heatervalve. The 2nd pic shows the aux waterpump in yellow attached to heatervalve.