I know this may sound stupid, but which way does the coolant flow through the radiator? I have an '87 iS, in which I recently replaced all the hoses, thermostat, and waterpump. Now, two months later I'm overheating. The upper radiator hose is hot as hell and the lower hose is barely warm. Without knowing which way the coolant flows, I can't tell if its the new thermostat not opening, or my radiator is now clogged. Can anybody help me with this information?
-
-
~~~~~~~~~~~~~~~~~
'90 325i sedan daily driven
'85 325e coupe also a daily -
Thank You...
According to the flow diagram, it appears that my radiator is clogged, so the coolant flowing to the thermostat never gets hot enough to open it.Comment
-
The coolant always flows from the top of the radiator through it by gravity to the bottom. What you describe is perfectly normal and means that your radiator is working great. My guess is you need to bleed the system properly to get air out, or you have head gasket problem creating exhaust gas to get in the system and stopping the flow. If you really think the radiator is the problem pull it and check the flow with a garden hoseThe difference between porcupines and BMWs is that porcupines have the pricks on the outside!Comment
-
Yeah, I’m pretty sure the thermostat gets heated by the fluid in the cylinder head, so it would open and allow coolant to flow to the top radiator hose. It is possible that the thermostat has failed or there’s too much air in the system. Filling the old style system is very slow because the reservoir tank is just barely higher than the top radiator hose and it’s hard to tell if the coolant has filled the block and head. It takes a few heat cycles to get my sons ‘87 purged of air.My son has the 1987 325e, 2 door, 5speed
I daily the 1989 325i, 4 door, 5speedComment
Comment