so, i finally replaced the fan clutch, but it had no effect, so i think that my old fan clutch was good still. when idling, the car temp still seems really high (3/4) when the a/c is on. also, when the a/c is on, the aux fan runs. here's the thing, when i remove the k6 and k7 fuses, the aux fan still runs. is this normal? i did the high temp and low temp radiator switch tests. they were good. when i shorted the wires, the low temp wires triggered the aux fan on, but when i shorted the high temp wires it did not trigger the aux fan. i heard clicking which sounded like it came from the k6 k7 fuse area. i checked the aux fan resistor it regestered below 6ohms (around 2ohms). any ideas? '84 318i. thx
overheating
- Thread starter imtjm
- Start date
how fast does it heat up? If you start it cold do you get bubbling in your expansion tank if you start it up with your cap off?
perhaps your head gasket is letting exhaust into the coolant. (this causes quick and bad overheating.)
Perhaps your radiator is close to clogged.
Perhaps your thermostat is stuck closed.... no that couldn't be becasue your aux fan turns on and clearly your radiator gets hot....
One of the first two maybe?
perhaps your head gasket is letting exhaust into the coolant. (this causes quick and bad overheating.)
Perhaps your radiator is close to clogged.
Perhaps your thermostat is stuck closed.... no that couldn't be becasue your aux fan turns on and clearly your radiator gets hot....
One of the first two maybe?
Yeah it sounds to me that there is air in your cooling system and that the problem with your auxillary fan might not be related. Take the rad cap off when the car is at running temp and see if there are bubbles being released. Try to bleed the system free of air. If that doesn't work then you will probably have a dodgy cooling system.
Does driving at low revs with plenty of air-flow have a positive effect on the engine temp? If it still remains high then it will almost certainly be the cooling system. If the temp is higher without your a/c on then the aux fan aint kicking in at all so must have a bad connection somewhere.
I know this probably isn't very helpful to you but you have to rule out all the possibilities. It's likely that all the aforementioned problems are contributing to a higher engine temp.
Let us know how you get on.
Does driving at low revs with plenty of air-flow have a positive effect on the engine temp? If it still remains high then it will almost certainly be the cooling system. If the temp is higher without your a/c on then the aux fan aint kicking in at all so must have a bad connection somewhere.
I know this probably isn't very helpful to you but you have to rule out all the possibilities. It's likely that all the aforementioned problems are contributing to a higher engine temp.
Let us know how you get on.
would a bad water pump cause overheating or above normal operating temp? since I have the above normal operating temp when I'm in stop and go traffic and when idling, i was wondering if it could be the water pump causing the problem, since when I'm driving down the highway i do not have the problem. thx
The lower hose should be cooler. The hot water goes into the radiator from the top.
I knew my thermostat was buggered when driving at night time when it was about 5 degrees celcius (thats damn cold) and my engine temp would actually decrease. Or when i'd be sitting in traffic and the temp gauge would creep up. My thermostat was working but it wasn't working properly and so my car was running too cold on the freeway and too hot in the city and, as a result my fuel eco. was shot to pieces. If the water pump isn't working then your engine will be constantly hot, so that's obviously not your problem.
There is no definitive answer but taking all these variables into account you should be able to tell if your thermostat is gone.
I knew my thermostat was buggered when driving at night time when it was about 5 degrees celcius (thats damn cold) and my engine temp would actually decrease. Or when i'd be sitting in traffic and the temp gauge would creep up. My thermostat was working but it wasn't working properly and so my car was running too cold on the freeway and too hot in the city and, as a result my fuel eco. was shot to pieces. If the water pump isn't working then your engine will be constantly hot, so that's obviously not your problem.
There is no definitive answer but taking all these variables into account you should be able to tell if your thermostat is gone.
what happens when you install a thermostat upside down (this is for an '84 318i it is in line of the radiator hoses)? Your car overheats quickly, it starts to thunderstorm, you rip out the darn thermostat and flip it over, burning your arms in the process because you are too stupid to realize that you shouldn't be doing the thing when the engine is hot, but you are too mad to care. it was suppose to be a simple installation, no real effort involved except loosing hose clamps and swapping out the thermostats. i forgot the most important part about fixing stuff, tune my brain's head space and timing before I do anything.
after reinstalling the thermostat, the car did not shoot into the red, but i'm sensing that it may not have solved my high operating temperature problem though. it is running a hair over 1/2 with the a/c on in stop and go traffic and it's about 70-80ish out. i'll know tomorrow in the heat of the Texas day if it goes to 3/4 with a/c on in stop and go traffic as was the case with my old thermostat.
i don't think having the thermostat upside down would have damaged the thermostat, or could it? any comments on that?
does anyone know what the normal operating range with a/c on is for '84 318i? anyways, i was reading bentley and it says you can disconnect one of the wires going into the ICU if you are driving in a hot environment. I do not have the manual in front of me, so i do not know which wire, but it is listed in the manual. has anyone tried this?
thx
after reinstalling the thermostat, the car did not shoot into the red, but i'm sensing that it may not have solved my high operating temperature problem though. it is running a hair over 1/2 with the a/c on in stop and go traffic and it's about 70-80ish out. i'll know tomorrow in the heat of the Texas day if it goes to 3/4 with a/c on in stop and go traffic as was the case with my old thermostat.
i don't think having the thermostat upside down would have damaged the thermostat, or could it? any comments on that?
does anyone know what the normal operating range with a/c on is for '84 318i? anyways, i was reading bentley and it says you can disconnect one of the wires going into the ICU if you are driving in a hot environment. I do not have the manual in front of me, so i do not know which wire, but it is listed in the manual. has anyone tried this?
thx
S*** i forgot to mention that the thermostat has to be pointing the right way up...
I don't think it'll damage the thermostat having put it in incorrectly but you might've damaged the new gasket.
Take it all out again, get a new gasket, and put the 'stat back in the right way up and that might cure your problem.
Is there any leakage from around the thermostat?? Did you buy a Behr thermostat??
I don't think it'll damage the thermostat having put it in incorrectly but you might've damaged the new gasket.
Take it all out again, get a new gasket, and put the 'stat back in the right way up and that might cure your problem.
Is there any leakage from around the thermostat?? Did you buy a Behr thermostat??
'84 318i doesn't need a gasket b/c it is not fixed onto the engine. It's in line with hoses going to the sensors, the radiator, and the water pump. funny thing that all other inline parts have a directional arrow except the thermostat. the old one was Behr, the new one is some other german name from NAPA (Wahr i believe). neither have directional arrows. anyways, no overheating yet, and wouldn't you know it, it rained again today so it was cooler out. still maintaining a hair over 1/2 in stop and go. won't know for sure positive until i run it during hot temps.
has anyone disconnected the wire going to the ICU as bentley suggests during hot temperature days? thx
has anyone disconnected the wire going to the ICU as bentley suggests during hot temperature days? thx