overheating problem

[alexander pastelblau]

hey to all i am new to classic cars i am 20 so this is my first 2002 , my 2002 is overheating from some time now, i remplaced almost all : the water pump , 320i radiator, new head gasket, refurbished head, bmw blue coolant with destilated water, radiator cap, new hoses, and a pusher fan and still when going up hill or in traffic it overheads, in the highway dont, y try to take out the bubles the best i could,  reving the engine will presing the top radiator hose , i dont have a termostat so it supose to be always cold, i dont have space for the oem fan with the new radiator , and i dont have heater any info is greatly greated 

[dlacey]

If you don't have a heater, is the heater circuit blocked or bypassed? If it's bypassed then this can be a cause of overheating, as this "short circuits" the radiator, causing most of the water to just circulate thought the cylinder head and water pump and never get cooled.

 

Edited June 29, 2019 by dlacey

[jimk]

4 hours ago, alexander pastelblau said:

i dont have a termostat so it supose to be always cold

The thermostat not only controls the flow from the radiator, but i controls the recirculation warm up flow from the head outlet back to the pump suction.  I shuts off the recirculation warm up flow when the engine reaches operating temperature.  Need the thermostat too keep it cool!

[coloincaalpine RIP 2021]

+1 JIMK.     You need a T-Stat to allow the water to stay in the radiator long enough to cool, otherwise, it creates the snowball effect and keeps getting hotter and hotter and hotter. Also, how does your "pusher" fan function, I.e.: temp switch and relay,manual switch?   IMHO,  pusher fans can impede air flow through the radiator if they are not on a low temp switch. Is your 320 radiator new? If not, was it flushed and inspected?

Good Luck,

dq

[Mike Self]

You don't say whether you have A/C or not, but the A/C condenser can also block airflow through the radiator, contributing to overheating.  

 

And...since the factory thermostat is at the junction of three hoses, how are you joining those hoses without a thermostat?  Or did a PO do some jury rigging?  Perhaps the hoses are not correctly connected.  At any rate, you do need a thermostat for proper cooling.

 

mike

[Jim Blaschke]

Take block plug out and see if you have anything coming out. Mine was blocked solid with crud. 

['76mintgrün'02]

Before pulling the block's drain plug (under the exhaust manifold), you might want to hang a shower curtain under the car;  funneling the precious blue coolant into a clean container.  If it stays clean, you can pour it back in when you're done.

[Mike Self]

7 hours ago, '76mintgrün'02 said:

Before pulling the block's drain plug (under the exhaust manifold), you might want to hang a shower curtain under the car;

And then when the plug is out and the coolant is all drained from the block, take the block drain plug down to a hardware store or auto parts house and find a brass drain cock that will fit the hole, preferably a drain cock with a nipple to which you can attach a short length of hose and direct the coolant into a bucket or drain pan.  Then you can re-hang your shower curtain and (hopefully) escape your significant other's wrath!

 

mike

['76mintgrün'02]

31 minutes ago, mike said:

find a brass drain cock that will fit the hole

 

something like this?

 

[coloincaalpine RIP 2021]

Yes, though in metric.I think 19x1.50mm