1985 K100 RT That didn't run...does now with issues!

[Filmcamera]

I have just done this and found that removing the radiator was the easiest way to go to get to the temp sensor.  Once that was done it is pretty simple job, though you will need a 19mm ring spanner to remove the sensor, a socket cannot fit on and an open ended spanner is too wide.

[Laitch]

Laitch one involves draining and removing the radiator the second method involves . . .

So you wrote, but my reading stopped after the first sentence following 2/.

Anyway, Supershooter, do the radiator method, especially if you don't have another sensor as a substitute. The radiator fins could probably use a thorough cleaning. Drain the coolant by first removing the radiator cap then emptying from the lower hose connection.

[Martin]

A 19mm socket fits fine, on the 75 and the 100 2V, maybe the 4V is different.
Regards Martin.

[Filmcamera]

On my 4v at least there is an tube connection protruding out of the engine just to the left of the water temp sensor meaning there is not room to get a socket on, I think it has something do with CA emissions?


20161121_115535.jpg (48.49 kB . 768x575 - viewed 720 times)

[Martin]

I just did a remove and replace sensor last week and that fitting was not evident. The way I went in, all that was required was a 19mm socket an extension bar and a ratchet. :dunno
Regards Martin.

[Filmcamera]

Must be either a 16v or CA model only thing - just my luck huh?!?!

[Supershooter]

Thanks Guys

I was going to go in via air box removal route but the radiator removal makes sense too. I appreciate the advice.

Supershooter

[Supershooter]

How do the wires going to the sensor come apart?


Supershooter

[Filmcamera]

That looks like the water temp sensor. 
The connector just pulls off, it does not have the little wire across the top you need to push down like some of the connectors.


If it is a little stuck some gentle persuasion with a small screwdriver where the tabs connect with the sensor may help.

[Inge K.]

Open (or remove) the wire clip at the red arrows, so it go clear of the barbs at the green arrows.

[Supershooter]

Inge K, does the wire clip spread apart by the red arrows or pull out from the opposition side?


Supershooter

[rbm]

Spread out from the red arrows.  Maintain control of the wire, otherwise they go shooting off into the deepest most inaccessible areas of your garage, never to be found.  Needle-nose pliers are your friend.

[Supershooter]

Got it apart, Thanks for the help!  Now I need to get a deep meteric socket to get the sensor removed.


Supershooter

[Filmcamera]

Got it apart, Thanks for the help!  Now I need to get a deep meteric socket to get the sensor removed.


Supershooter

It is a 19mm nut. I used a ring spanner to get mine off btw

Sent from my SM-G935F using Tapatalk

[Supershooter]

A new 19mm deep socket and a its off.


Bench test showed 4540 ohms at 68-70 F, resistance should be around 2500 at 70 F. I boiled some water, resistance went down to 800. Should have dipped to around 250.


So if I understand correctly my water temp sensor is telling the bike its cooler than it actually is. Hence, the cooling fan did not start and run the last time I ran the bike and it puked antifreeze. But does that explain anything when it comes to not starting?


Dustin

[Laitch]

So if I understand correctly my water temp sensor is telling the bike its cooler than it actually is. . But does that explain anything when it comes to not starting?

Yes, Dustin, it could explain starting trouble. What's the air temperature when you're trying to start this relic?

If the engine is getting excess fuel because the sensor is signalling cooler conditions than actually exist, it will be difficult to start. That's flooding. In post #115 you stated that the plugs were wet and that you had spark. That's one of the signs of flooding and post #116 recommended testing the coolant temperature sensor, and that's why we've all gathered here on this beautiful Sunday. Run the test again. If you get the similar results, replace the sensor.

[Supershooter]

Laitch,
I keep the shop where she’s stored between 50-74F. I’ll get a new sensor coming.
Thanks

[Laitch]

I keep the shop where she’s stored between 50-74F.

Luxurious! At least you're relatively warm when your bike disappoints you.  :2thumbup:

[Martin]

If the sensor or the connector is bad the information the FIC gets is the engine is cold so it richens up the mixture. This causes the engine to flood. If you get stuck out on the road there is a way to get it started. Remove the spark plugs and let it air out for fifteen to thirty minutes. Replace the spark plugs and remove the fuel pum fuse number 6 marked krafftsoppe. The next part is better with two people but can be done with one. Start the bike, it should start on the residual fuel left in the combustion chamber as the engine dies ram home the fuse. With a bit of throttle manipulation the bike will run albeit badly. At traffic lights you will have to keep the revs up or it will cut out. TMG suggested unplugging the four pin harness to the pump as an alternative to removing the fuse. Either or what ever you find easiest. There is now a two part DeoxIT ( the second tin puts a gold coating on the pins) which should be used on the connector, a bit of heavy silicone grease around the edge of the connector would help to keep out the water.
Regards Martin.

[rbm]

Bench test showed 4540 ohms at 68-70 F, resistance should be around 2500 at 70 F. I boiled some water, resistance went down to 800. Should have dipped to around 250.

Did you take your measurement between both spade terminals?  Or between one spade terminal and the body of the sender?  If the former, that's the wrong technique and your conclusions may be wrong.  If the latter, then your diagnosis is correct.

[Supershooter]

Removed the fuel return fitting, no wonder the fuel lines kept breaking and spewing gas all over my legs.


Supershooter

[Timbox]

Glad I saw that, I am sure that is something I should be doing.  I would guess mine is the same :(  Thanks to you I will have to go dig a little deeper sense the parts are still on order.  Thanks SS for pointing that part out.

[Supershooter]

RBM,
I took the reading with the multimeter touching space terminal in the fitting, but it sounds like I need to test differently. So I need to have one lead on the body of the sensor and the other on a spade? Does it matter which lead touches the body of the sensor or spade, or one spade or the other?


Tim,
Sorry to break the news, the alternative is not pleasant, and the fitting is $8.00.

[rbm]

Yes, you need to connect one lead  of the multimeter to the body of the sensor and the other lead to either one of the spade terminals.  Which one doesn't matter.  There are two thermistors embedded within the sensor; one lead of each goes to a spade connector and both of the other leads are common and connected to the body.  Both thermistors have the same values and same response curves which is why it doesn't matter.

[Supershooter]

Upon retesting of the water temp sensor the reading came back at 2170 and 2222 on the spade connectors at room temp, and 269 for both spade connectors when placed in hot water, slightly below boiling. These seem to be inspect, or am I wrong?


Supershooter