water temp sensor issue

Post Fri Jul 29, 2005 9:08 pm

i have recently noticed that my leccy fan (91/99degC-but set to 91) has started coming in about 3mm further up the stock e30 gauge than it normally does (usually comes in just above half, noc coming in just below 3/4 of course this is still within normal limits howveer it worries me in traffic.....

now do u reckon this is down to the bmw brown temp sensor playing up there for it appearing to come in later but actually still coming in at normal actual temp..... or my switch for my leccy fan in the rad which is only a few yrs old playing up and coming in later than usual...

in any case i have fited a bypass switch just in case to turn my leccy fan on if needs be or for some doughnut/burnout action

Karan

Post Fri Jul 29, 2005 10:39 pm

Have you had this setup working Karan? (Brown temp sender and 91/99c Thermo switch?) I have this one mine, guess ur using the E36 switch?

Mine also comes in about 3/4 up the scale, so like you I just have an overide switch.

My conclusion was that the 24valvers run hotter?

Andy

Post Fri Jul 29, 2005 10:44 pm

Andy325i wrote:Have you had this setup working Karan? (Brown temp sender and 91/99c Thermo switch?) I have this one mine, guess ur using the E36 switch?

Mine also comes in about 3/4 up the scale, so like you I just have an overide switch.

My conclusion was that the 24valvers run hotter?

Andy

yeh ive always had it working......

just used to come on lower down the scale before.....

i have a feed into the sensor in rad then 2 outpts currenlty only one is in use-91degC as i only have a one speed fan whereas i believe some M3s had 2 speeds with the faster coming on at 99degC

Post Fri Jul 29, 2005 10:58 pm

Dam! There goes my theroy then!

Back to the drawing board!

Let me know when you slove it mate

Andy

Post Fri Jul 29, 2005 11:03 pm

Andy325i wrote:Dam! There goes my theroy then!

Back to the drawing board!

Let me know when you slove it mate

Andy

does ures acrually come on though at 91?

Post Fri Jul 29, 2005 11:06 pm

never measured the temp (any idea how?) just comes in way too hot for my liking (3/4 up the scale)

Andy

Post Sat Jul 30, 2005 9:59 am

Karan,

The only way to know if the problem is the radiator temp switch or the temp gauge (brown) sender, is to measure the temperature of the radiator itself. I have a temp probe for my multimeter for this, but not sure how you could do it without. When I installed an electric fan on Paul (Shinobi1's) car, I did measure the radiator temperature, and the switch did seem to be quite accurate.

As for Andy's problem, he may need to get a lower temp radiator switch. You can get an 80/88 degree switch under part number 61 31 8 361 787. This is a direct replacement for the 91/99 switch. For the record, I'm using the lower temp switch on my conversion, but have it wired for dual speed operation because of the aircon install.

Cheers,

Ian.

Post Sat Jul 30, 2005 10:40 am

ian332isport wrote:Karan,

The only way to know if the problem is the radiator temp switch or the temp gauge (brown) sender, is to measure the temperature of the radiator itself. I have a temp probe for my multimeter for this, but not sure how you could do it without. When I installed an electric fan on Paul (Shinobi1's) car, I did measure the radiator temperature, and the switch did seem to be quite accurate.

As for Andy's problem, he may need to get a lower temp radiator switch. You can get an 80/88 degree switch under part number 61 31 8 361 787. This is a direct replacement for the 91/99 switch. For the record, I'm using the lower temp switch on my conversion, but have it wired for dual speed operation because of the aircon install.

Cheers,

Ian.

Ian.... do u remember which one u put in my car? how much is this switch roughly then? ill try measuring somehow the temp but my multimeter doesnt have a probe... i guess some kind of thermometer will do LOL

cheers
Karan

Post Sat Jul 30, 2005 4:46 pm

Karan wrote: Ian.... do u remember which one u put in my car? how much is this switch roughly then? ill try measuring somehow the temp but my multimeter doesnt have a probe... i guess some kind of thermometer will do LOL

cheers
Karan

Hi Karan,

I don't recall which one we fitted to your car. Ste bought the switch, and I fitted it. They sell for about Ãƒ”šÃ‚£24, so not cheap for what it is

I guess any sort of thermometer that can be touched against the radiator fin's would work. My temp probe fit's snugly between the fin's, and gives a pretty accurate reading.

Ian.

Post Sat Jul 30, 2005 9:35 pm

ian332isport wrote:
As for Andy's problem, he may need to get a lower temp radiator switch. You can get an 80/88 degree switch under part number 61 31 8 361 787. This is a direct replacement for the 91/99 switch. For the record, I'm using the lower temp switch on my conversion, but have it wired for dual speed operation because of the aircon install.

Cheers,

Ian.

Thanyou again Ian

will order one of these on monday