K11 Owners Group

[WidgetMan]

I agree, its very satisfying when a simple fix cures a longstanding problem. But this bike is a real case study in Murphy's Law - 'If anything can go wrong - it will.'

So the rail goes back on, the basics are reconnected, and lo the fuel pump charges and the engine turns over, and better yet she starts!! So we leave her idling to warm up and come back ten mins and a cuppa later to find she is still idling and also nice and warm. So we decide that whilst we have the skirts off we would have a go at balancing the airflow with a home made manometer. So we plug it in to each port on the throttle rail in turn to decide which to use as a benchmark. We decide that as pots 1 and 2 are about equal we would use them. Just as we are about to start the process of adjusting pot 4 there's a quiet pop and a jet of clear liquid shoots up 5 feet from somewhere on the other side of the bike!

I quickly shut off the ignition and we rush round to find water bubbling and fizzing from the reserve tank and its cap lying on top of the Motronic case. Bless her, she's overheated, 4 pots was just too much heat. Even though the radiator was hot all through for some reason the fan had not kicked in. So now its diagnosis time for an overheat.

Milky deposits were found on the oil filler cap which could indicate a cylinder head leak. However, it could also just be water evaporating from oil that has been stood for some weeks whilst the bike has been worked on. She is due an oil change anyway so the next day the oil was dropped into a sawn off milk container. All that came out was clear as mud - thankfully no milk. I also emptied out the water to check for oil contamination and thankfully that came out clean and clear as well, so a blown cylinder head gasket looks unlikely.

Continuity between the Motronic and the fan relay was checked OK and the relay swapped for the fuel pump one just to check it was working - it was. The fan was freewheeling and ran when triggered by connecting a 12v battery to its connector under the fuel tank. So now I suspect a faulty temp sensor (a web search revealed that apparently these loose sensitivity over time). It is tempting to put in an overide setup with a separate sensor and switch that bypasses the Motronic's control of the fan but the Motronic seems to use the input from the temp sensor to vary the richness of the fuel so I have to continue with Plan A and look into the whole fan/radiator setup another time.

A replacement sensor arrived today so, whilst most of the bike's water is pooled on the garage floor, I'll take the radiator off and flush water through it. For completeness sake I'll check the thermostat by bunging it into a mug of boiling water and waiting for it to trigger (Its only a few months old and I've found out the hard way that they can take a couple of minutes to respond), and then set about replacing the offending temp sensor. I'll post the next installment over the weekend if anyone's interested.

Maybe I should switch this post to another tread as it has moved on from the original. I'm sure someone will let me know if I should.

More to follow .....
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'93 K1100LT (tatty and ex-police - the bike, not me!!.)
K - 75,000 miles, me - 4000 miles.

[Flying Duck]

I split this off from the other thread for you.

The water and oil pump (same assembly) have a seal on the shaft which separates the water and oil. That could be your issue iif you have water in the oil.
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93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[Phil Marvin]

[Flying Duck]

Don't know. Never had a leaky one. I try to crash or sell my bikes before they hit 60k.
_________________
93 LT (x2)
94 RS
86-97 K75F(K75/100/1100 Frankenbrick)
86 K75C w/paralever, hi perf cams,TURBO!
91 & 92 K75Ss
91 K1
86 custom K100
14 WR250R
IBA #17739 (SS1K, BBG, 50CC)
Buy parts HERE

[Phil Marvin]

[Tim (Midland Section)]

So Tim, What was the running problem? Found the other post now 22:20 fri . As for your fan, do a search, there is a thread about overriding the fan. Also there are TWO temperature sensors, one for the guage alone, t'other for engine management. Look in the Tech stickies, there may be resistance vs temp charts to prove a good / bad sensor. If it seriously overheats, the Motronic, first lights a dash lamp, & second, kills the engine. Had my overflow cap go off like you describe, after an Austrian 3000ft hill climb in 35C sun. Only difference was that my arse was right above at the time. No ill effects caused.
HTH
http://www.k11og.org/forum/viewtopic.php?t=4944&highlight=temperature+sender
http://www.k11og.org/forum/viewtopic.php?t=4759&highlight=
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Regards Tim,

Grey haired riders don't get that way by pure luck
1996 Guzzi Cali3 LAPD
1972 750 Commando
G6HRN
#485