Radiator Fans - BMW Luxury Touring Community
 
LinkBack Thread Tools Display Modes
post #1 of 14 Old Aug 15th, 2014, 7:58 pm Thread Starter
Senior Member
 
Join Date: Aug 2007
Location: Las Vegas, NV, United States
Posts: 114
Unhappy Radiator Fans

I got the trike back today (2000LT) from BMW Motorcycles of Fort Worth after a clutch/seal replacement, engine service. Ooops, the radiator fans run from key on continuously! I have checked the connection to the water pump temp sensor, OK. Anyone have any idea what they might have done to make this happen? Fans should not run until water is hot! Their tech is off today and Saturday, cannot ask him.

Jerry

BMWMOA # 134919
2000 LT Hannigan Trike
1986 Suzuki TM400 (gone)
1957 BSA 500 cc Twin (long gone)
1955 BSA Golden Flash (longer gone)
1950 or thereabouts HD 165 cc 2 stroke! (gone in 1954)
scubajgp is offline  
Sponsored Links
Advertisement
 
post #2 of 14 Old Aug 15th, 2014, 8:02 pm
Senior Member
 
zippy_gg's Avatar
 
Join Date: Jun 2004
Location: Kennesaw, GA, USA
Posts: 8,126
Re: Radiator Fans

If just one fan is continually on I would suspect an incorrect connection.
If both fans are on continuously I would suspect a relay.
Unfortunately it takes a bit of disassembly to get there, so best to wait until your tech gets back.

Gilles & Kathy
BMWMOA# 154719
IBA# 71594
2011 Ostra Gray RT
06 Mercedes-Benz E350 Estate (parts and people hauler)
2012 BMW X3 (parts and people hauler)
86 Porsche 911 Cabriolet (my "new" baby)



For her I climbed the highest mountain!
For her I swam across the deepest ocean!
For her I walked through the largest desert!
And then she left me... She said I was never home!!!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
zippy_gg is offline  
post #3 of 14 Old Aug 15th, 2014, 8:10 pm
Wrencher Extraordinaire
 
jzeiler's Avatar
 
Join Date: May 2004
Location: Hazel Green, AL, USA
Posts: 13,308
Re: Radiator Fans

The temp sensor on the back of the cylinder head (near the coil pack) if disconnected will trigger the fans on at key turn. Easy check but you have to pull some body panels.
Attached Thumbnails
Click image for larger version

Name:	Temp sensor.JPG
Views:	147
Size:	47.2 KB
ID:	62961  

John
2009 K1300GT Red Rocket
2009 R1200GS (Gone)
2005 K1200LT Ocean Blue Blue Wizard 110 K and counting...
2006 Bushtec Turbo+2 Spell
2004 330 Ci Convertable
K4AN

Have ridden a Motorcycle in all 48
But lack DE, MA, RI and CT with the 2005 LT

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
jzeiler is offline  
 
post #4 of 14 Old Aug 15th, 2014, 8:18 pm
Senior Member
 
sailor's Avatar
 
Join Date: Nov 2004
Location: Montreal ,QC , Canada
Posts: 1,171
Re: Radiator Fans

Quote:
Originally Posted by scubajgp View Post
I got the trike back today (2000LT) from BMW Motorcycles of Fort Worth after a clutch/seal replacement, engine service. Ooops, the radiator fans run from key on continuously! I have checked the connection to the water pump temp sensor, OK. Anyone have any idea what they might have done to make this happen? Fans should not run until water is hot! Their tech is off today and Saturday, cannot ask him.
Could be a bad radiator fan relay (does not fail often), but more probable is a bad Engine-temp-sensor (located into cylinder head of cylinder #4). First, check if connector of this sensor is not plugged correctly or if a wire is damaged, the behavior is the same: fans will run full time when values from sensor are out of limit.
See this post for more details: http://www.bmwlt.com/forums/showthread.php?t=61960

Better if you have a GS911, but you can do a rough check of resistance (ignition OFF) using an OhmMeter. This PICASSA picture tutorial is for the k1200RS, but the K1200LT has the same sensor - only the end connector is a bit lower:
https://plus.google.com/photos/10148...82307964672065
At 70F (or 21 Celcius), the reading should be close to 2500 Ohms. When engine is hot, you should read 220 (hot) to 170 Ohms (very hot). Leave ignition OFF for these tests.

-------------------------------------------------
John (Montreal, CANADA)
K1200RS (2002 IceBlue/Red - 96,000 miles)
-------------------------------------------------
Think twice before you hit [SUBMIT REPLY] - famous quote by another member:
"The value of this board is not founded on dismissing the ideas of others, but by posting to share our experiences and what we've learned from them."
sailor is offline  
post #5 of 14 Old Aug 16th, 2014, 2:05 am
Senior Member
 
Join Date: Feb 2007
Location: Helsinki, Finland, Europe, Northern hemisphere
Posts: 594
Re: Radiator Fans

Considering the fact bike being back from clutch rebuild, the heat sensor has been (and still is) disconnected or wire damaged

Born to be wild so why not

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
C-A-D is offline  
post #6 of 14 Old Aug 16th, 2014, 10:54 pm
Senior Member
 
casualemt's Avatar
 
Join Date: Jun 2009
Location: Oak Harbor, WA, USA
Posts: 676
Re: Radiator Fans

+1 On JZ's reply, I know from my own experience that when the head temp sensor located on the back of the head goes bad, the fans will kick on prematurely, so I could see that if the shop disconnected the head temp wire, it would kick the fans on immediately.. pretty easy check/fix, just got to pull tupperware on the left side, you can see the head temp sensor sticking out of the rear side of the head, follow the wire, and the connector is just under the section of the tupperware that is under the seat area. Or you could ride it back to the shop, and tell them that they need to fix it...

RICH CANNON
2000 K1200LT "a great ride"
2002 GL1800 powerful, but boring..(gone)
1979 XS1100 (gone)
1986 VT500 Ascot (gone)
1972 Honda 500-4 (gone)
1961 Lambretta (way gone)
1962 Allstate Compact (gone but not forgotten)
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by casualemt; Aug 16th, 2014 at 10:55 pm. Reason: forgot something
casualemt is offline  
post #7 of 14 Old Aug 17th, 2014, 7:52 am
Senior Member
 
mtrevelino's Avatar
 
Join Date: Apr 2002
Location: Williamsburg, VA, USA
Posts: 2,556
Re: Radiator Fans

If the fans kicked on immediately, wouldn't the repair shop (mechanic) notice that before giving you your bike back? They must of been in a hurry to get that bike out!

Mike Trevelino
Williamsburg, VA
2008 RT
2000 LT - Totaled at 99,960 miles


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
mtrevelino is offline  
post #8 of 14 Old Sep 12th, 2014, 1:12 pm Thread Starter
Senior Member
 
Join Date: Aug 2007
Location: Las Vegas, NV, United States
Posts: 114
Re: Radiator Fans

Wow, what a great forum!! Great knowledge! We have been on a motor home trip to South Dakota, so was not able to tackle this issue until today.

The sensor is open, infinite resistance. I do not have the tools to remove/replace the sensor, so back to the shop she goes! (I don't know how anyone can get a wrench on that sensor!!!)

I really appreciate all the input from all of you, Thank You very much!!

Blessings.

Jerry

BMWMOA # 134919
2000 LT Hannigan Trike
1986 Suzuki TM400 (gone)
1957 BSA 500 cc Twin (long gone)
1955 BSA Golden Flash (longer gone)
1950 or thereabouts HD 165 cc 2 stroke! (gone in 1954)
scubajgp is offline  
post #9 of 14 Old Sep 12th, 2014, 3:37 pm Thread Starter
Senior Member
 
Join Date: Aug 2007
Location: Las Vegas, NV, United States
Posts: 114
Re: Radiator Fans

Well, I took another look, and I was able to remove the defective sensor. Was not too bad after all!!

Now to find a replacement!!!

Jerry

BMWMOA # 134919
2000 LT Hannigan Trike
1986 Suzuki TM400 (gone)
1957 BSA 500 cc Twin (long gone)
1955 BSA Golden Flash (longer gone)
1950 or thereabouts HD 165 cc 2 stroke! (gone in 1954)
scubajgp is offline  
post #10 of 14 Old Sep 12th, 2014, 10:28 pm Thread Starter
Senior Member
 
Join Date: Aug 2007
Location: Las Vegas, NV, United States
Posts: 114
Re: Radiator Fans

Yes, you would think so!!

Jerry

BMWMOA # 134919
2000 LT Hannigan Trike
1986 Suzuki TM400 (gone)
1957 BSA 500 cc Twin (long gone)
1955 BSA Golden Flash (longer gone)
1950 or thereabouts HD 165 cc 2 stroke! (gone in 1954)
scubajgp is offline  
post #11 of 14 Old Sep 21st, 2014, 7:03 pm
Junior Member
 
Join Date: Aug 2012
Location: Livingston, TX, USA
Posts: 10
Re: Radiator Fans

Quote:
Originally Posted by scubajgp View Post
I got the trike back today (2000LT) from BMW Motorcycles of Fort Worth after a clutch/seal replacement, engine service. Ooops, the radiator fans run from key on continuously! I have checked the connection to the water pump temp sensor, OK. Anyone have any idea what they might have done to make this happen? Fans should not run until water is hot! Their tech is off today and Saturday, cannot ask him.
About LT fans. I have had a continuous problem with a blown fan fuse since I purchased this LT, my 3rd, in July of 2014. The fuse would blow after the fans cycled a couple of times. I was finally able to get to a dealer two weeks ago who diagnosed the problem as a bad fan motor, excessive axial play and high friction in rotation, on the right side. New motor and fan installed, still blows the fuse. Dealer now telling me the other motor is bad as well . The tech exchanged fans, left side, with another bike in the shop and cycled them 6 times with no failure. I think that a failure of both fans, excessive current draw by both, as highly improbable. One caveat, the bike is a 2009 with only 4,992 miles on it when I bought it, and it came from the Midwest. Lots of humidity and too much time sitting.
I searched the forum for this type of failure. Nothing popped up. Any thoughts, similar experience??
rktman is offline  
post #12 of 14 Old Sep 21st, 2014, 7:57 pm
Wrencher Extraordinaire
 
jzeiler's Avatar
 
Join Date: May 2004
Location: Hazel Green, AL, USA
Posts: 13,308
Re: Radiator Fans

If both are bad then both were subjected to the same environment. Lack of use and high humidity could have driven the corrosion that caused the excessive play. Also the 09s were assembled with the last bits off the assembly line, just say'in.

John
2009 K1300GT Red Rocket
2009 R1200GS (Gone)
2005 K1200LT Ocean Blue Blue Wizard 110 K and counting...
2006 Bushtec Turbo+2 Spell
2004 330 Ci Convertable
K4AN

Have ridden a Motorcycle in all 48
But lack DE, MA, RI and CT with the 2005 LT

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
jzeiler is offline  
post #13 of 14 Old Sep 21st, 2014, 8:06 pm
Junior Member
 
Join Date: Aug 2012
Location: Livingston, TX, USA
Posts: 10
Re: Radiator Fans

That is the only thing I could come up with as well. I had another 09, wrecked in April, that was flawless. Thought I could get lucky again, lol.
rktman is offline  
post #14 of 14 Old Sep 22nd, 2014, 4:01 pm Thread Starter
Senior Member
 
Join Date: Aug 2007
Location: Las Vegas, NV, United States
Posts: 114
Re: Radiator Fans

OK, the fix is in!! I have followed the recommendations of this forum, and have successfully repaired this LT trike!! First on ordering the replacement sensor....I ordered from a BMW parts firm, didn't hear anything, called 2 times, nothing. So, I ordered another from 2 Wheel Pros. They were superb, received the part in 2 working days as advertised. In order to make sure I would not destroy the new part, I first put a 2.2K resistor on the connector to the fan relay, and sure enough, the fans did not start at key on. I was concerned that something else was wrong downstream from the sensor. I checked the voltage also, about 4.2 volts DC. So, I plugged in the new part, and yep, fans did not start at key on. All put back together now, behaves as it should! I want to thank everyone on this forum who contributed to my success!!

Jerry

BMWMOA # 134919
2000 LT Hannigan Trike
1986 Suzuki TM400 (gone)
1957 BSA 500 cc Twin (long gone)
1955 BSA Golden Flash (longer gone)
1950 or thereabouts HD 165 cc 2 stroke! (gone in 1954)
scubajgp is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the BMW Luxury Touring Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome