Over heating 318

[E36bitch]

Hi

I've got a 1997 318 i which refuses to switch the electric fan on when the A/C / Climate control is switched off.

I've changed the sensor at the top of the rad, no change, the hoses are hot , top and bottom. The electric fan cuts in and out if the A/C is on. But if left off the temp guage eventually heads for the red and the warning light comes on.

BMW said it might be the ECU not sending the message to the fan to switch on?

Any thoughts, or am I in for a airconditioned winter..............

[Sk1d]

Has your car got 2 fans, 1 belt driven 1 and 1 electric 1??? Its just that normally the electric fan, if its on the bumper side of the rad, will only kik in when the air-con is on anyway. If this is the case you might want to start lookin 4 other problems like ur thermostat stuck shut or a broken water pump...

Just a thought...

[Autotechnica]

That's correct, the 318 has 2 fans. 1 electric fan is for the A/C and the other is a belt driven (not electric) fan which is always running. The belt driven fan is driven by the waterpump pulley. This cools the radiator. Also, make sure you have the fan shroud in place (plastic peice covering the clutch fan). This peice is needed to create a vaccum, your rad will not properly cool if this isn't in place.

Chances are if the clutch fan doesn't spin, the bearing is broken, the fan is seized or the belt is broken or missing. Either way, have someone inspect the fan and replace if necessary.

It's unlikely that your thermostat is not working properly. However, if it's been a while since you've replaced that, replace that as well. Usually the engine will run too cold if the thermostat is broken.

Bry

[Sk1d]

I was thinking more along the lines of the thermostat being siezed shut rather than stuck open, causing lack of coolant flow in the block and eventual overheating. But u've got a point about the fan shroud...

[Autotechnica]

Good point. There's an easy way to test it though. Squeez the larger rad hoses which run into the thermostat housing. You should hear "clicking" noises which is the sound of the thermostat plates opening and closing. If you don't hear it, it's probably seized.

Bry

[E36bitch]

Hi Guys,

Look I'm no expert but I can only find 1 fan under here.

I think the cars got the M40 4 cylinder "ladies engine" in it, not a straight 6.

Can I send some VGA pics?

[Sk1d]

If u can post any pics on here, that'd b a winner. Can always have a look 4 u then...

[Autotechnica]

There's only one fan you can see easily which is located infront of the engine under the hood (behind the radiator).

The other fan is located infront of the radiator but behind the front bumper. So it's pretty much hidden. You can stick your head under there and you should be able to see the fan blades through the front of the bumper.

The fan that you should be worried about is the one that's mounted INSIDE the engine bay, the one you can see easily. You really can't miss it, either it's there or it isn't.

Where are you located by the way? The M40's are a European only model as we don't have them here in North America, we only have the M42 and M44 which are also 4 cyl.

Bry

[Autotechnica]

next pic

sorry caption should read

"old M40 and M42" not M44

[Autotechnica]

Here's a picture of my car's front end taken apart. As you can see, there is yet another fan mounted in the front of the car behind the bumper. This fan is for the A/c only and does not affect your engine temp, so forget about this fan. As I said before, the engine fan is the important one.

Hope my pictures helped to clear things up.

Bry

[Sk1d]

Sweet engine bay dude, specially tha charger sat on top... Nice 1...

U'll have 2 excuse this woosy lookin engine, i kno it dun look like tha monster Autotechnica's runnin...