[zugre]

Hey, two weeks ago when i was changing oil, noticed that my coolant reservoir is bellow the low line (didnt see coolant at all in the reservoir) so i buy the new motul motocool expert coolant, flush out entire cooling system 3 times and put in the new coolant and bleed air in the system. Reservoir at full line. After 3-4 warm ups amd cool downs, checked the reservoir and added coolant again to the full line at reservoir. At this time i already spent exactly 2500ml (like it says in the k9 service manual book) and i thought this is it, the air in the coolant system is bleed out perfectly, so i put the plastics back on and ride the bike daily. After 2-3 days checked the reservoir level and the coolant is almost at the low level line. So if all cooling system is exactly 2500ml(with reservoir) why im losing coolant. I checked and everything is fine, radiator, hoses, hose clamps, everything is good and there is no leak anywhere…

 

[zugre]

hmm i found this just now, seems like broken hose?!
Only solution is the new hose or there is another fix like high temp silicone or glue?

 

[Beairsto Racing]

We don't glue hoses, we replace them...but are you sure it's the hose leaking and not the radiator itself, in that bottom corner?

 

[zugre]

We don't glue hoses, we replace them...but are you sure it's the hose leaking and not the radiator itself, in that bottom corner?

Im not sure, i will take off the hose tomorrow and see for cracks. Also to mention, when i take of the old coolant, there was a black dirt/a ton of very very very very small black pices (maybe hose rubber?) it seems like black rubber from the hose but not sure

also you said the radiator, but how can radiator be damaged on the back side.. im not sure what would damage the radiator at this place (btw, 40k kms at clock and the bike is in perfect condition)

 

[Beairsto Racing]

Radiators vibrate and flex, the core can fail...it's 13 years old.
It looks to me like you have a small leak that is weeping in that area.
Do you have a coolant system pressure tester?

 

[zugre]

Radiators vibrate and flex, the core can fail...it's 13 years old.
It looks to me like you have a small leak that is weeping in that area.
Do you have a coolant system pressure tester?

I am checking things out right now. Just warms up from 40c till 105 wih fan on.. nothing happens
Then goes for town ride half hour, comes home, nothing happens… i didnt see that water spot on radiator again. I will see tommorow again
No i dont have pressure tester

But im losing coolant as i said before, service manual says 2400ml of coolant. I put that ammount and was perfect to the full line when bike is cold.. now on cold its almost at low line. If there was air in the system thats okey but i put exactly 2500ml (and bleed air from two bolts) so there is no sense

 

[BillV]

Find a radiator repair shop. They will have a pressure tester. Pay attention to the possibility of a head gasket leak. Might the wet area be from a leak in the front that's getting blown through the radiator core? There can be air pockets in the head that don't get purged until you run it for a while. The OEM hoses are fairly robust. It seems highly unlikely that one would shed particles that end up circulating in the coolant. You could of course remove the hose and check the ID. Was the old coolant anything unusual? Something sounds fishy there.

 

[zugre]

just to inform, i was wrong about this issue!

1. I found that, that water leak spot on the radiator was caused by bike wash lol... the night before i spot that water leak, i was washing the bike and then garaged it, so the water did not dry out completely. (i found that yesterday, after the same situation happens after washing the bike again).

2. Also, in the service manual found that 2500ml of coolant is in the engine + 250ml in reservoir, so 2750ml overall. (instead of 2500 overall as i thought before).

so, everything is as it should be.

Till now, im at full line in reservoir with exactly 2600ml of coolant in the system. As im riding for a while in the future, maybe some air would purge again and i will add that coolant which have left (150ml), back in the reservoir.