Post by: Doodaadog on July 12, 2018, 05:51:27 AM
So have an ongoing saga of recommissioning my K11 which was holed up not running for 8 years...
Seem to have everything working and all fluids renewed.....my problems now alll relate to cooling...
Symptoms: no reading at temp gauge and fan not coming on, resulting in coolant overheat light coming on.
What Ive tried....
Tested thermostat which opens at the correct temps....
Cleaned contacts on the bottom water sensor (under the water pump).....no difference....
Fans spins freely when moved by hand
Tried to put 12v direct to fan....but does not operate
Checked contacts on relays (all clean)
Fuse is ok
...from what Ive read the bottom sensor just runs the temp gauge? So that has nothing to do with fan....guessing mine is toast...but dont know how to test.
So what signals the fan to operate?....is it the sensor on the coolant manifold on the rad?
Could someone help with a test sequence and next steps please?
Regards Greg
Post by: John Lang on July 12, 2018, 06:59:54 AM
Post by: Laitch on July 12, 2018, 07:21:03 AM
So what signals the fan to operate?....is it the sensor on the coolant manifold on the rad?It's the sensor in the box depicted in the attached image.
(http://www.motobrick.com/gallery/1/1601-120718071533.png)
Post by: Scott_ on July 12, 2018, 07:46:45 AM
Fan wiring, Violet/Yellow +12v, Brown- ground.
There is a "test" sequence that you can do to check the operation of the fan relay/fan circuit. You should be able to find it in the stickies section.
The fan relay is controlled by the motronic, and the temperature is measured by the sensor mounted behind the fan on the small coolant riser tube bolted to the block. Power for the fan relay should be from fuse #7
You can check and see if you have +12v at the temp gauge on green/black. (key on, kill switch on, side stand up, engine off)
Wires at the gauge:
Green/Black- +12 in from fuse #1,
Black- +12 out from gauge to temperature sensor at water pump,
Brown- ground for backlight
Grey/Blue- +12 for backlight.
Post by: Doodaadog on July 12, 2018, 09:01:35 AM
Regards Greg
Post by: Doodaadog on July 12, 2018, 09:13:03 AM
Mine is similar but not the same as your schematic...According to my workshop manual...seems the K1100 LT and RS even differ?
Regards Greg
Post by: Laitch on July 12, 2018, 11:46:18 AM
Hi LaitchThat diagram is from MaxBMW's K1100 parts fiche (https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51711&rnd=07242017). What BMW does with these diagrams is they will use the same diagram for many models even though there might be slight differences.
Mine is similar but not the same as your schematic...According to my workshop manual...seems the K1100 LT and RS even differ?
Post by: bizzaro on July 12, 2018, 03:18:28 PM
image.jpg (58.72 kB . 768x573 - viewed 1706 times)This is the fan test that Scott mentioned to check and see if the wiring, circuits(relay), and fan are working. On center stand, ignition off, side stand up, ground pin one of your diagnostic plug with a wire to a good ground. The diagnostic plug is right under your seat. Mine is a black 3 pin with a blue cover. (And I assume yours should be the same.) With the ignition off, Remove the cover and ground Pin 1. There is a good ground right behind the coils. Turn on the ignition, but do not start the bike. With the 1 pin grounded on the diagnostic plug and ignition on, Count to 5, and Remove the ground. Your fan should now pulse on and off till you turn off the ignition. If it doesn't you need to start testing your components. I just replaced my fan and have a pretty good photo montage which I hope to post as soon as I learn how to crop, size, and orient photos so as not to waste bandwidth.
Post by: bizzaro on July 12, 2018, 04:54:03 PM
Post by: Scott_ on July 12, 2018, 06:55:11 PM
Post by: rbm on July 12, 2018, 08:46:11 PM
Documentation Link: http://www.nt-guru.com/bmw/Motronic%20Fault%20Codes.doc
Post by: Doodaadog on July 13, 2018, 05:47:45 AM
Post by: Doodaadog on July 13, 2018, 08:13:25 AM
Tested supply to the temp gauge...
Have 12v to the backlight and 12v supply from fuse....
Only milliamps to the black wire
Ground is good.
Fan test:
I can hear the relay firing and checked the loom feed to fan and sure enough 12v was pulsing through.
So conclude the fan feed circuit is ok.
Will next check continuity to fan.....but suspect fan is toast....
Have already tried putting 12v direct to fan.... fan no likey
Thank you all for your invaluable advice with this saga...
Regards Greg
Post by: bizzaro on July 13, 2018, 08:44:42 AM
Unless the wiring to the fan has an issue, sounds like your fan is toast. So you have options now. And just so ya know, buying the BMW replacement for $350, shouldn't be one of them! :yow I replaced my fan with a Spal Fan. If you go this route You will need to use the old housing to mount the Spal Fan in place. You can also just replace the motor. And there is a European co. Making a really nice replacement for about $140 I think it was. You can peruse this thread here, http://www.motobrick.com/index.php/topic,11345.0.html and here are a few links to options.
https://www.amazon.com/Spal-30100402-Puller-6-5In-15Amp/dp/B01LXF8FWE/ref=sr_1_3?s=automotive&ie=UTF8&qid=1529794718&sr=1-3&keywords=spal+cooling+fan+6.5 (https://www.amazon.com/Spal-30100402-Puller-6-5In-15Amp/dp/B01LXF8FWE/ref=sr_1_3?s=automotive&ie=UTF8&qid=1529794718&sr=1-3&keywords=spal+cooling+fan+6.5)
/https://www.amazon.com/gp/product/B075FSCHZC/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1 (http://www.motobrick.com/https://www.amazon.com/gp/product/B075FSCHZC/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1)
https://www.tills.de/product-112-113-158.html
Post by: Doodaadog on July 13, 2018, 10:30:25 AM
If I could get the brush an easy cheap fix....will investigate
Cant easily remove fan from rad as the fixings are so corroded, going to plump for used fan and rad...(guaranteed tested) by the seller....as Im selling this brick on once Ive got everything working again.
Post by: bizzaro on July 13, 2018, 05:17:52 PM
Post by: The Mighty Gryphon on July 13, 2018, 06:23:50 PM
Geez, that looks hauntingly familiar!
Yep, seen that too...
Post by: Martin on July 13, 2018, 07:07:23 PM
Regards Martin.
Post by: bizzaro on July 13, 2018, 07:56:23 PM
Post by: Martin on July 14, 2018, 01:40:19 AM
Regards not so retired Martin.
Post by: Doodaadog on July 19, 2018, 09:27:03 AM
You can buy the cooling fan motor as a separate item
http://www.euromotoelectrics.com/BMW-Motor-Radiator-Fan-K-models-1983-1995-p/fan-k427m.htm
Post by: Laitch on July 19, 2018, 10:04:20 AM
New UpdateIs that what you did, or did you go with the whole radiator/fan substitution to accelerate you down the road to Flipdom?
You can buy the cooling fan motor as a separate item
Post by: Martin on July 19, 2018, 06:03:50 PM
Regards Martin.
Post by: Doodaadog on July 20, 2018, 05:42:28 AM
Bought a used rad and fan combo for 60GBP.......swapped fan onto mine....was very pleased to hear it run on fan test....so have a spare rad to go on eBay and recoup some dough.
Next is to find the 2 coolant sensors at reasonable cost.....
Or dig a hole in the yard and throw some money in!......