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1Back to top Go down   temp sensor issues ? ... solved  Empty temp sensor issues ? ... solved Sun Dec 25, 2011 8:05 pm

charlie99

charlie99
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gday guys .....

for all of you that have had temperature issues i think i have the fix .....

rt showed me a temp sensor which he had pulled from his bike ....the diagnosis was by changing it he solved his temp sensor - fan operation issue .....there was more involved with the fan mechanism but we'll by pass that .

anyhow ...upon putting a mutimeter accross the temp sensor terminals i found there to be no issue ...both legs of the sensor mesured just right .

today i was exploring electricals and came accross an odd reading when probing the temp switch assembly .

(actually i was putting a bypass switch to ground out the temp sensor leg to activate the fan as an override )

i couldnt get anything from the sensor at all ...open circuit ...crikey !!!!

ok so doing some probing and removing the connector at the back of the sensor ( i thought the contacts on the connector was sure to be the issue )

i got conductivity from both legs to the right places ...efi and temp switch ...hmmm

i probed the connectors on the sensor mechanism and earth .....nada ....nothing at all ....what the ????

so i pulled the sensor ...(blocking the fluid release of corse) ... and measured it in my hand ....perfect ...

i reistalled it again ....dang nothing at all ....i retightened it ....still nothing

i measured between the stub and the engine in case of high resistance on the one bolt holding all together ....all ok

hmmm what to do ....

first thing i noticed on closer inspection was an aluminium crush washer and a brass housing on the sensor ... "click "

so with a little emory paper (wet and dry actually ) i cleaned up the brass collar of the sensor .....and the crush washer ...which was quite pited ...but looked only as surface corrosion and verry slight at that .there was no evidence of the white powdery corrosion that normally always accompanies this type of problem ...

any how the short version is ...dang the conductivity returned .....i would be guessing that most of us have been through the replacement process AND replaced the crush washer in this process .

my fix is ....clean up the surfaces where the sensor bonds ....

the threads i thought would create a good electrical contact ....and if you could clean them properly. probably would ...

so if you have a temp sensor related issue ....try this process first.



hope this helps someone



Last edited by charlie99 on Sun Dec 25, 2011 8:29 pm; edited 2 times in total

    

blaKey

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Brilliant deduction Charlie.


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Neil
K100RS 1986 RED!

Dress for the ride and the potential slide.
    

RicK G

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Have heard of that but never come across it my self. The copper oxide only conducts in one direction. You would remember the old copper oxide diodes Charlie.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

Albyalbatross1

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I had never heard of copper oxide diodes. So this a natural property of copper oxide? What sort of currents could they carry?

    

Inge K.

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Remembering that I did have a metal plate rectifier on my very first small bike, Suzuki 50cc `70.

wikipedia.

Inge K.

    

charlie99

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ah! ...yes i knew them a selanium rectifiers as well ....thanks for the link inge


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cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%Otemp sensor issues ? ... solved  Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

RicK G

RicK G
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@Albyalbatross1 wrote:I had never heard of copper oxide diodes. So this a natural property of copper oxide? What sort of currents could they carry?
They were the bees knees at the time but were prone to overheating and had high internal resiatance but were much more portable than a vacuum tube diode.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 2004 K1200GT 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

8Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Mon Dec 26, 2011 10:50 pm

RT

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Good to see you spending valuable off time for the good of mankind Charlie.
I need a heater here today, the world has gone crazy, and I think I better stiffen the suspension a bit till I can get back to normal food.
Cheers RT

    

charlie99

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oh ! just have to report ...back from a trip to day with other local members.

this is the first time i have acheived what seeemed to me to be about 25 kilometers per litre or 4 liters per 100

the sensor must have been working to some degree whether it is temperature related expansion of related components or lossy (high resistance ) possibly causing the temp sensor to read the engine at a lower temp than was actually occuring .

thats a massive 15 - 20 percent better running machine than normal

i have to say that the old "gerty von clickandshift" purred well today

    

10Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Wed Dec 28, 2011 3:02 am

Albyalbatross1

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I was impressed with Charlies improved performance yesterday. So have just spent the last hour doing the same with mine. I will go for a run on saturday and see if I can mprove on my 20k ltr.

I was discussing with a mech mate at work. he said charlies fix was spot on. The bike is no longer running CHOKED! I am going to check my old ute out tomorrow as well.

    

Dennis

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Ahh, the old smoke and mirrors (electricery) stuff. Well I can add my little bit from the mechanical perspective to help close the loop on this annoying issue. The temp sensor telling the EFI that things are cold (when really they're not) means a rich mixture is supplied. Hence black smoke and increased fuel consumption as well as reduced performance. Then the richened mixture washes the oil film from the cylinder walls and oil consumption increases. If this is prolonged, in extreme instances the oil can be smelt to contain fuel. Faulty thermostats can cause similar problems if they fail to close, which causes very slow engine warm-up and possibly not reaching correct operating temp at all. 1 way to check if the thermosat is functioning correctly is to observe engine temperature on a long downhill run. If the temperature drops excessively it is possible that the thermostat is not closing off fully and should be replaced. Remember, EFI engines are designed to operate within a narrow temperature range.

    

12Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Wed Dec 28, 2011 4:20 am

charlie99

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good advice dennis


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%Otemp sensor issues ? ... solved  Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

13Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Sun Jan 15, 2012 2:53 pm

Oldgoat

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Really nice work Chaz. Cool


OG

    

14Back to top Go down   temp sensor issues ? ... solved  Empty Temp sensor Sun Jan 15, 2012 4:25 pm

Rjtrucker

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My sons 1985 K100RS has over 100,000 miles on it and all of a sudden the bike will not start when hot. I did change the temp sensor and still have the same problem. I dont know if this has anything to do with the brass or aluminum crush washer that is on there. Or do any of you have another idea?


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Ron S
NJ USA
74 R90/6 cafe project
93 K11LT
85 K100RS
85 K100RS turbo project.
And a load of K100 projects and parts.
    

15Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Mon Jan 16, 2012 4:39 am

ReneZ

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Measure the resistance of the sensor between pins 10 and 13 on the ECU plug. The bike has a safety that it can be run, but not restarted if it detects that its too hot. Look at Berrt's fault finding pages on this site related to the cooling water temperature.



Last edited by ReneZ on Mon Jan 16, 2012 12:39 pm; edited 1 time in total


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Greetings from Florida! Having a 'new' K  :cyclops:    Surprised-o: 

Rene


BMW K100 - 1985 (0030029) temp sensor issues ? ... solved  Rain
BMW K1200GT - 2003 (ZK01223)
    

16Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Mon Jan 16, 2012 5:10 am

charlie99

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as rene suggests it could be reading (resistance value ) verry low in ohms when it gets hot .......could it be a partial short to ground on the cables from the temp sensor .....from memory its really tight as it goes through the throttle bodies and onto the fuel rail let alone up the frame to under the tank (cable chaffing?) the under seat connections that rene suggest is ideal for measurement of this specific problem.

just a note ,,whilst several of us were away on a "tech " weekend at about 10.00 am (atmosphere was about 25 c and in the sun so could have been hotter ) we measured 3 bikes and found them within about 10 ohms of each other (around 1760 ohms )

rj ...i wonder if you have thought about the fuel regulator ,,,its tucked behind the tbs ...and we have seen some weird issues with them sticking open ... we havent established if this is temperatue related as well yet ...tank temperatures often get high also ...

could be thermostat partial operation as well ?does the fan operate at all ? durring or before this event ...or even if left running long enough ? we have seen issues there as well .

my initial investigation was due to lack of fan operation that made me suspect and start investigating .

food for thought ?

    

17Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Mon Jan 16, 2012 8:17 am

beanoldboy

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i had a wee giggle at "cable chaffing", it brought me to thought.
someone on this forum has , in passing , lauded the virtues of lanolin instead of wd40. Out of curiosity ( yes i am going through some cats!) i bought o can, and sam i am , converted. try please, its made from sheep smiles or something. i now dip my bikes ( 7 now ) in it at night !
I gonna start a new thread



Last edited by beanoldboy on Mon Jan 16, 2012 8:21 am; edited 1 time in total (Reason for editing : I gonna start a new thread)

http://www.airware.com.au
    

18Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Mon Jan 16, 2012 8:41 am

charlie99

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temp sensor issues ? ... solved  44271


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%Otemp sensor issues ? ... solved  Au-log10

'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
    

19Back to top Go down   temp sensor issues ? ... solved  Empty Re: temp sensor issues ? ... solved Tue Oct 20, 2015 1:24 am

Kafflut

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@Dennis wrote:Ahh, the old smoke and mirrors (electricery) stuff.  Well I can add my little bit from the mechanical perspective to help close the loop on this annoying issue.  The temp sensor telling the EFI that things are cold (when really they're not) means a rich mixture is supplied.

Mmm.. If you read my struggles with too fast idle in my posts on the subject you will understand why I'm interested in this. I think I must try cleaning that little sucker. I was wondering what the temp sensor/EFI connection was for.

Dennis, do you think it's possible that my fast idle(an understatement at 2000 rpm) could be due to EFI thinking it's cold outside?

http://bmwk100k75.weebly.com/
    

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