Coolant boiling normal?

[stRobe]

Im a new s4 owner so i need some help with the coolant thing.

 

When we 'top-up' the coolant, do we pour in the coolant into the plastic container at the side OR into the radiator cap?

 

Are these 2 seperate cooling systems on the bike?

[Winners]

Under normal situation, you should just top up the coolant in the expansion tank, which is the plastic container. When the engine is warmed, the expanded coolant in the radiator will flow into the expansion tank. When the engine is cooled again, the vacuum created inside the radiator will "suck" back the coolant from the expansion tank. All the above are taken in consideration that your radiator cap is working normally. Furthermore, the coolant system is a "close loop" system. Therefore, it shouldn't need frequent replenishment, unless there is a leak.

[bikeyroo]

No issues with removed thermostat in Genting and Fraser Hills. Starts normally in the morning pretty quick. No extra modifications needed. Was cruising average 150 and whacking on some stretches in hot sun and at night, no issues with temperature. Some trunk road was riding in heavy rain for hours. Some stretches on highway in rain. No issues as well. My conclusion is it can be removed in ALL operating conditions in Singapore and Malaysia without any further mods.

 

As for the above, did the water level in the reserve reservoir go down and you have to top up?

[xHxHx]

i have the same boiling issue

 

but a week ago i change the radiator cap and everythings back to normal

but aweek later which is now. same thing happen again. coolant start to boil. i top up water and from vivo to jurong. when i encounter red light water start to drip...(coolant leaking)

and coolant boiling..

so wat can i do now?

[Marcheline]

I just change my radiator cap for $8. Now no more boiling problem

 

Woah! I changed mine for $15 at Unique. Mech says its original Honda cap. Saw the number 1.1 on the cap.

[Pplater]

As for the above, did the water level in the reserve reservoir go down and you have to top up?

 

Remains constant. If water level goes down abnormally it means there is leakage or evapouration/boiling liao... usually radiator cap problem?

 

Anyways.. for those that haven't notice, S4 runs much cooler on semi-synthetic coolant. On fully syn, its much hotter. I usually suka suka switch between both...