Pegging out the Engine Temp

[woodlandsprite]

So I took the Confident Ridercourse / BRC2 today - the RX3 drew some attention and questions of course

But one thing that had me nervous after doing a bunch of stuff at low speeds in 1st and 2nd gear, the engine temp kept creeping up and several times it hit the high mark and blinked at me. I have adequate amount of coolant in the radiators, and the overflow bottle is showing fluid level between the low and high mark.

I could not tell if the fans were on behind the radiators - when the bike was in Neutral, I did check and they were NOT on. Are they supposed to be on and moving??

Riding home normally I had no issues with the temp maxing out, but my bike does occasionally like to creep itself up to 4 bars.

[roots]

Mine comes on just about every ride here in California. I can hear them on after I shut down. I make sure I keep my key on after I kill the engine. I believe the fans turn off when the key is turned off. Anyway, you should see and hear them and they should be on if you are reaching 4 bars.

I'm sure some of the experts will give you some instructions for evaluating their functionality.

Good luck!

[Jay In Milpitas]

First, congratulations on completing BRC2!!!!

Now on to the cooling fans. They are a "dumb" system in that they are not computer controlled. Power goes to the temperature switch in the left radiator (if I recall correctly) and when it reaches a certain temperature it sends power to the fans.

Start with checking each connector to be sure the wires are fully inserted and the pins are not messed up. You might have to relocate the fuel tank, not necessarily remove it, to access all the connectors.

If connections are good, then you will need to test the temp switch itself.

If it was only one fan not running, I would have suggested checking only that. Since it's both, start with common power source.

Good luck.

[SpudRider]

I agree with Jay.

The thermal switch located at the bottom of the left radiator is supposed to activate both fans when the coolant temperature reaches 82 degrees Celsius. See post #7, and post #8 in the following thread.

http://www.chinariders.net/showthread.php?t=15595



If you short the connectors in the plug shown above, the radiator fans should activate if the ignition key is on. If shorting the plug works, the thermal switch is defective, and CSC will send you a replacement. If shorting the plug doesn't work, you have a loose connection elsewhere in the wiring.



Even if the thermal switch is good, I suggest you purchase a spare. The switch can be killed by vibration. The following, radiator fan switch is equivalent to the switch employed by the Zongshen RX3. This switch is designed for the following Suzuki and Kawasaki motorcycles.

Suzuki

GSX-R600 97-05
GSX-R750 96-08
VL/VZ800 01-11
DL1000 V-Strom 03-09
GSX-R1000 01-04
SV1000 03-07
TL1000R/S 98-03
GSX-R1300 “Hayabusa” 99-07

Kawasaki

Ninja ZX-6R 2003-2004
ZX636 2003-2004
ZX600 2003-2004

http://www.ebay.com/sch/i.html?_from...witch&_sacat=0





Other RX3 equivalent parts are listed in the following thread.

http://www.chinariders.net/showthread.php?t=15532

[Weldangrind]

Originally Posted by woodlandsprite

So I took the Confident Ridercourse / BRC2 today - the RX3 drew some attention and questions of course

Good for you, Sprite! Excellent decision.

[SpudRider]

Originally Posted by Jay In Milpitas

First, congratulations on completing BRC2!!!!..

Originally Posted by Weldangrind

Good for you, Sprite! Excellent decision.

X3. Rider safety education is money well spent.

[woodlandsprite]

Once again you all prove to be very helpful. I had a feeling I'd seen something on thi forum about the cooling system workings but didn't think to go through that one linked by Spud! I have unfortunately managed to catch myself a cold so not sure if I'm up for troubleshooting the bike today.

Is there a recommended method for shorting out the plug?

I can also check the wiring, though I really do not relish pulling the tank off right now as its full of fuel...though I suppose I could siphon it if necessary.
Speaking of tanks, is mine the only one that leaks gas out the lid when turned upside down? I noticed some folks storing their tanks upside down in photos of doing valve work. I'm quite sure I had it sealed tightly when I had it off last time but it definitely leaked gas!!

[BARLOW]

first temp switch i have ever seen that put power to fans, and not ground ... but i do most cooling work on cars ... only my quad is liquid cooled, and i didnt trust the switch, si i just keep the fan on any time it is running, by connecting the 2 wires that went to the switch

[woodlandsprite]

Well, I found some electrical wire to make a jumper - and it looks like unless I was doing it wrong (I jumpered the socket in the plug and the fans did not turn on while the ignition key was in the on position), I'm going to have to take the tank off/moved to follow the wiring ....which is going to have to wait for another day *sigh* I wonder if I knocked something loose while doing the valve work over the holidays. *grumble*

[Jay In Milpitas]

First get yourself healthy.

You did correctly jump the connector contacts. I've been known to just use a paper clip. So since it's likely that power is not getting to the temp switch, it appears the next connector is upstream from there at the diode. Yes, it sits under the tank as shown in these pics:
http://www.chinariders.net/showpost....7&postcount=24

Kind of right where fingers go while playing with intake valves. I don't know if it's visible from underneath without raising the tank. Might be able to just lift your rear up.

[woodlandsprite]

thanks for the link and info Jay (and Spud too of course!)
Hopefully I won't have to move the tank completely to have a look.

[woodlandsprite]

*sigh* I have an electrical issue. Gerry is demonstrating the famous and wonderful CSC customer service and is helping me troubleshoot my bike remotely.

[SpudRider]

Thanks for posting the update, Sprite. Please do let us know how, and when, the problem is resolved.

[woodlandsprite]

Alrighty, sorry for the delay - the diagnosing and repair took all afternoon on Saturday, but in the end, I've got it fixed and the fans are running as they should be now.

So to recap: Radiator Fans were not kicking on and while doing a lot of low speed manoevering during a training class, the bike overheated. Coolant levels normal (though I did take the opportunity to top up the radiator which was not quite completely full when the bike was checked on the sidestand).

What I was able to troubleshoot on my own:
1) Shorting out the plug to the temp sensor did not turn the fans on
2) pulled the tank to check the next connector upstream - connector was tightly connected, no signs of corrosion.

Somewhat at a loss of what to do, I hopped on the phone, hoping Gerry could point me in a direction - he did better than that, he helped me diagnose over the phone and gave me a suggestion for repair.

So here's what we did:
1) Checked voltage at the plug to the temp sensor and found it to be nonexistant (when the ignition key was turned to on but bike not running), and seriously low while the bike was running
2) Checked voltage at the next connector upstream, and also found it to be low
3) checked voltage at the fuse box for the relay in question and found power to be fine
4) checked voltage at the black triangular connector near the solenoid (the connector is the one next to the cylindrical connector with the purple ends), found power to be fine (all pins hot)

This meant that there was a wire that had gone flaky between that black connector and the diode. Possibly where the the wiring harness gets squished next to a bolt on the frame closer to the front of the bike.

The options presented to me were 1) get a replacement wiring harness and run that 2) button it back up and take it to a shop or 3) run a parallel wire - I chose option 3 - and I completed it with splice connectors/plier taps. A solder join would definitely have been more secure. Since I had to cut open the sheathing around the wire bundle that goes to the diode a fair bit, I secured the whole lot after the repair (new red wire) including the splice connector with self fusing tape. The other connector I did not do the same to, because it's pretty well shoehorned in place and hopefully will not work itself loose.

During the course of this adventure I learned all about the judicious use of paper clips for back probing and jumpering, how to use a wire tap/splice connector and I learned that I need to learn how to do a solder join. Also learned that the colors noted on the wiring diagram may not be consistent with what is in the bike.

Before putting everything back, I checked the voltages at all the connectors that I touched to ensure that i had power where I should, and at the correct value. After everything was buttoned back up, I made sure the temperature sensor was also working by leaving the bike idling to get the engine temp up to 3 bars, at which point the fans happily kicked on.

Now that I'm done with the repair and playing the what-if game in my head, I'm wondering if I was too eager to do the repair myself, because if something goes wonky down the line I'm not sure I'm going to be able to get those splice connectors off to attempt a soldered repair.

Ah well, and since it's always "photos or it didn't happen" here you are:



oops, one more thing - I had a tricky time getting the tank back on, probably because i had been moving things all around, and the fuel lines generally didn't want to go back nicely under the tank. I did ask if there was a trick or tip for disconnecting the tank and Gerry suggested disconnecting the fuel line below the fuel filter - rather than the 2 lines directly at the tank.

[rjmorel]

Wow excellent job woodlandsprite. You did something I would tremble to do and you actually fixed it. Bonus points for the dirty hands too. True spirit of Zongyness. I've used those connecters in the past and never had any trouble with them. You can unfold them and take a screw driver and pry out the metal part that makes the connection but you may never have too. Fixable situation anytime. You may want to write your self a note on what you did and a little wiring diagram so if your ever out on a trip you'll remember what you did and be able to go directly to the problem area. Put the note in your owners manual.
At 59 I find I'll forget what I did to my bikes and several years later find myself going thru the same scenario and wasting time trouble shooting the thing all over again. Then I have the senior OH Yah moment and remember. SIGH, rj