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08 450 EXC Boiling over

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So I replaced the radiator fluid on my 08 KTM 450 Exc...

I refilled it with 1 L of Engine Ice... I noticed on my skidplate there is left over coolant after I run the bike and take the skid plate off. The coolant was traced up the frame to the overflow from the radiator.

Now even after I take the bike just up and down the street it seems to spit coolant out of the overflow.... Like it is boiling over...

Plz help... I am thinking about draining and refilling the radiators again... :thumbsup:

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when you drained it did you drain the cyclinder head? if all you did was crack the plug on the radiator there will still be coolant in the head, this needs to be drained as well. when you refilled the system did you bleed the air out of the head? the highest part of the cyclinder head is above the lower radiator hose, if you dont bleed the air out of it your bike will constantly overheat because of the trapped air in the system. i dont know where the bleed and drain bolts are on the 08 head, but on the 07 the drain bolt is just below the exhaust, and the bleed is just above the spark plug hole on the forward side of the head. your manual should have in it the right way to bleed the system, it may take more than once to get right, with so little coolant in the system any amout of trapped air will send you into boilerland. good luck!!:thumbsup:

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I have a 08 450 exc and when i replaced the radiator fluid i drained it by taking off the water pump cover. After i replaced the cover, i fIlled the radiator and never had a problem and its been about 200 miles now.

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K so I think I possibly overfilled the radiator. I took some of the fluid out and it isn't spilling out from under the frame like before. It isn't boiling over that's for sure, cuz I can't hear the boiling noise from the radiator that you normally hear. Also, is the cap supposed to prevent the fluid from entering back into the overflow drain tube?

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I have a 08 450 exc and when i replaced the radiator fluid i drained it by taking off the water pump cover.

what?

you have specified instructions through the bike manual or engine manual,

there are two screws to play with, one is under the exhaust, which you open and drain the entire system into a tank or so, you can watch this being done in one of mcgoodies video's.

the other is when you fill it up again, it is just like cliffsherman said taking the air out, you fill the radiators with fluid, than open the screw and hear the air going out till some water start to flow, then close it and complete the radiator filling.

socalmedic- had the same issue, filled it up too much and got anxious over it spilling over the engine while riding,

while playing with it, took the water pump cover off as well so that was a bit worrying,

it was a great relief knowing it's nothing.

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The 08 manuel tells you to drain the fluid by removing the bottum screw of the water cover, so you might as well check the water pump impeller. After that fill it up and ride. In the manuel there is no mention of air bleed screws.

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The 08 manuel tells you to drain the fluid by removing the bottum screw of the water cover, so you might as well check the water pump impeller. After that fill it up and ride. In the manuel there is no mention of air bleed screws.

Exactly what I did.... and now I think I just filled it too full... it isn't spewing anymore:banana::thumbsup:

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In the manuel there is no mention of air bleed screws.

my bad,

talking about an RFS 2006,

i'm just so dumb sometimes :thumbsup:.

:confused:

Edited by mazungo

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