RaDiAtOr IsSuEs - United Bimmer Community

**jonspencer_1981** · 05-30-2007, 02:05 PM

Hi,

this is a follow up to a post I placed a few weeks back. Below is a picture of my radiator, where I think I have a problem.

If you remember, my radiator fan isn't working unless the AC is on. The coper plug blanks off a hole where I think (not sure) a temp. sensor should be. Next to it is a bunch of wires (3 in total - power, earth, ecu??? again, only assumption).
Does the temperature sensor just screw in here and then connect to these 3 wires?
If someone could post the same picture of their radiator, just so I can compare, or just if you can advise, I'd be v grateful!

Thanks in advance

**3050rpm** · 05-30-2007, 03:15 PM

Sorry the pic isn't better, but it should give you an idea...

**jonspencer_1981** · 05-30-2007, 03:21 PM

thanks. I'm presuming I've got the right wiring loom then?

**3050rpm** · 05-30-2007, 03:29 PM

I can't figure out what the brass plug is doing in your radiator, right where me sensor (or whatever is) goes.

**jonspencer_1981** · 05-30-2007, 04:04 PM

I think it must be a blanking plug. I had the radiator replaced when I bought the car, and it never had a sensor in to start with. The thermostat had been removed (which would explain the slow overheating), so maybe it is just the sensor that gores in there. I've had a look at a parts diagram, and that suggests the sensor fits there. We'll see I guess. Thanks anyway

**jonspencer_1981** · 05-30-2007, 04:06 PM

oh, btw, uk car! does that make any difference? by the looks of your picture, the rad filler tank is on the opposite side.

**3050rpm** · 05-30-2007, 04:13 PM

Right, I'm from one of the colonies, so I'm not sure of the left-right arrangement, plus I think BMW changed the position of the fill tank over the production run of the E36s. Smart idea to look at a parts diagram for your model year, but certainly a brass plug doesn't belong there, and without being overly alarmist I suggest you get it out, dissimilar metals exposed to a hot liquid environment don't bode well.

**jonspencer_1981** · 05-30-2007, 04:32 PM

well, the rad was fitted by an approved bmw garage. I think the sleeving for the temp sensor has the same compound, but I'll certainly investigate it. I'm 95% certain that those wires are related to the sensor, otherwise they'd be connected to something. They're not alarm wires (thats on the other side), and not to do with lights (as they all work). The only thing that doesn't work is the fan, and those are the only bare wires.
2 + 2 = ??

**3050rpm** · 05-30-2007, 04:35 PM

Well, I think you're on the right track...

**stevo** · 05-30-2007, 04:43 PM

jon, your radiator should have a temp sensor where the blanking plug is and you should also have a thermostat in your engine it looks as though some previous owner has had problems with overheating (probably the original temp sensor gone faulty) and decided the cheapest way would be to remove the sensor and thermostat but in the process they have disabled the engine cooling fan, check to make sure they haven't installed a manual switch somewhere to operate the cooling fan, or more likely they have had the engine cooling fan rigged to the AC switch which they used as the engine started to overheat.and it looks like the wires you have spare are indeed the wires for your engine temp sensor.

**jonspencer_1981** · 05-30-2007, 04:48 PM

thanks for your response. It was suggested to have the rad fan on a switch, but i don't want the engine to overheat after being switched off. The fan only works on AC backup as it should do. I just want to make sure the wires exposed are the correct ones for the sensor.
ps - new thermostat has been fitted (my dad gave same diagnosis as you have!!)
thanks. If you can confirm those wires are correct, or if there's any way of testing to make sure, then I'd love the help.
Thanks again,
Jon

**stevo** · 05-30-2007, 05:16 PM

I would say almost certainly the wires are for the sensor unit but you will need to go to a breakers yard and cannibalise another plug for the sensor from a wreck, I will check the colour coding of the wires tomorow after work as its just a tad dark outside at the moment.

**jonspencer_1981** · 05-30-2007, 05:21 PM

understandable, check your pm. I'm at work tomorrow, so you may be better texting or ringing.
cheers
Jon

**stevo** · 05-30-2007, 05:26 PM

no problem

**stevo** · 05-31-2007, 10:40 AM

heres a picture of what should be there
the colour coding of my wiring is ,left to right, black with green stripe, brown, black with white stripe. bearing in mind that my car is a 318se tourer.