Is there a way to get the fan to kick in sooner on an '03 KTM 640 Adventure? For whatever reason the bike is getting VERY hot lately. Never did this before. The only thing that's changed recently is I swapped the original coolant for 100% Engine Ice - seems like that stuff runs hotter! Just driving city traffic today within 2 blocks the temp is at 6 bars!! Last week it actually pegged at 7 bars & started flashing along with the red overheat idiot light. Fan kicks in at 6 bars, but I'd like it to come on sooner.
If the engine is running noticeably hotter since you changed the coolant, then I think you have your answer - something changed when the coolant did. I'd go after the cause rather than trying to mask the symptom with more cooling fan action. You wouldn't think the new type of coolant would cause the problem, so I'd next suspect you have some air in the system. - Mark
Good call - but if there's air in there, how do I get it out? I did the following to flush the coolant: --------------------------- 1) Drain old coolant (from lower connecting hose between the two radiators) - fill with distilled water - run bike w/cap off until thermostat pops open (see water turn colour suddenly). Drain that water... ...repeat step 1 three times...water is now clear. 2) Fill with 100% Engine Ice, run with cap off until thermostat pops open - coolant level drops slightly - top off, run again. Check level & top if necessary. --------------------------- I figure running with the cap off would allow any air to 'burp' out of the system ... is there something I might not be doing...?
Sounds like you're doing it correctly, but perhaps someone who has done it has some tips - these things can be tricky. I'm about to do mine, so any help appreciated. You might get on KTMTalk and see if anyone there has any tips. - Mark
Im not sure if this may help at all, But do you know if the Engine Ice coolant is ment to be pre-mixed with water or is already diluted when you buy it. Im not sure about this brand but I do know that if you use 100% Glycol type coolant the engine will run hotter than normal, It aparantly needs water with it to disipate the heat. We normaly mix straight coolant at a ration of between 33% & 50%. As I said may not be the problem but worth a thought though.
Had a similar thing happen when I changed coolant on my LC4E. The way the two rads top tank vent line runs (through the frame) will not allow the air to get out of the lhs rad. When refilling, I found out that I could not get back in the system the same volume that I took out!. So, filled as much as I could, then dropped the bike onto the lhs to let all the air escape from the lhs rad, stood it back up and then added the remaining coolant. Been OK since. Hope that this helps.
I agree with Mr. Nicolls(?). I use Water Wetter and you use a cap full per litre of water. It either has to be mixed, or you have an air bubble somewhere. Drain again and start over, just add coolant slowly. you might want to remove a couple hoses and try filling them first too. I haven't added any to my KTM yet, but in my other bike the temp dropped an average of 10 degrees Celcius.
ak - Engine Ice is already premixed w/de-ionized water (big "do not add water" warnings on the bottle). Like everything wrapped into one product - wetting agent (Water Wetter), antifreeze, and water. wjohnb - good suggestion I hadn't heard that, but I laid the bike down on both sides & the coolant level didn't drop gybeman - I may just try your suggestion - drain & refill. One question - wouldn't the water pump remove any air trapped in the system through the vent hose near the cap?
Did you open the bleed screw on the front of the cylinder head? Take a look thru the LC4 owners book and it gives a good diagram.
:huh Bleed screw? Where is this? I checked the owner's manual, but all I can find is a very limited description of radiator function on page 36. The spare parts manual for the engine has a breakdown of both the cylinder & head, but I can't find anything that seems like a bleed screw specifically. (Note: this is an '03 640 Adventure w/the high-flow head)
i bled mine about 3 weeks ago added some water wetter and cranked it up and purged the system with the cap off ...... try this if that doesnt work pull a return line to the radiator {top hose} fire her up and see what kind of fluid flow you are getting ... might have a stuck thermostat stuck closed that is dont run it out of radiator fluid though :eek1 fwiw im pulling the 640 motor tonight to put in the lc4 racing cam this week end im adding a rally fan to the throttle side radiator and putting both fans on a toggle switch along with the water temp sensor auto kick in if youd like ill take pics and post them of the extra fan ......... all the other goodies too if you guys and gals behave Barry akrapovic exh fcr cam rallye clutch springs yadda yadda yadda
Dual fans ... cool. How did you bleed the system? After filling/draining a few times, I simply ran the system with the cap off until the thermostat opened - I assumed this would purge the system of air.
I would love that. I also promise to clean my room (the garage) I have a '02 and have never found a blead screw. Do all the LC4 motors have them?
Been wanting to do this as I end up stuck in traffic a lot with 110 degree heat. This has a tendency to spike the engine temps (I hate to see that yellow blinking light). I haven't been able to find a good right side fan. Apparently you have. PLEASE let me know where/when/how I can get one too!!! I'll mow the grass ('02 Adventure)
Barry, just wondering if you had postthe pictures somewhere, I might have missed the thread and I am really interested by this right fan on the adventure. Thanks for letting us know Luc
sorry guys Linzi stole my bike :huh since her stator and RR went to shit on mutley this means my high ass dollar 640 is in gainsville till tommorow with a new racing cam , brand new akra header and pipe , fcr 41 , and me know where around :eek1 ............. have the fan stuff out in the garage and as soon as i make and adapter plate ill show you what i have done Barry
You actually think I'm gonna bring this thing back? (No, really...HUGE thanks for loaning me your bike, Barry. )
Just an update to the original post ... I've been doing some loose testing down here in Baja - 1st gear climbs, high-speed river washes, plus some country & city road miles. Seems to be working fine! I think it runs slightly hotter than before, but that may be because all my rides the past few months were in winter. Regardless, I flushed out the Engine Ice & put a 60/40 mix water/Prestone, plus about 5 capfuls of Water Wetter - so far I haven't gone over 5 bars! So far so good... On another note - MT-21's are pretty cool, but I think I prefer the 606 front for stuff down here.
