Coolant Overflow

This past sunday at the Firebird Raceway, my 2000 WR400 was filling up the coolant resevoir. Is this a sign of overheating? Blown head gasket? The temperatures weren't that high. It was probably 85 air temp and maybe 100*F track temperature. The track is a 11 turn 1.25 mile road course, so it had adequate air flow to radiators.

This is what it is there for!!!!!

I bet you when it got cool, the level dropped again.

The first thing that i would check is the radiator cap - 6 years old and after all it's only a cheap spring and a piece of rubber (subjected to heat and pressure) - tap washers don't last that long.

Secondly, check the plug to see if it's perhaps running a little lean - this can cause it to run a little hotter than normal ...

good luck ...

what would I check on the radiator cap? What effect does it have on cooling?

The rad cap pressureizes the coolant system, raising the coolant/water's boiling point. A weak rad cap would lower the boiling point send the boiling coolant into your res.

You are testing the radiator cap's ability to hold pressure. Or hold coolant in the cooling system if your radiator cap is more than a year old replace it. You can also search and order a 20 pound cap stock is 16 pound I belive after all this then start looking for a cooling problem.

Okay, the level has not dropped in the resvoir. Does that mean anything to you guys?

I'll definitely pick up a new radiator cap. Should I pick one up directly from a dealership or is there a recommended after market one?

What if the coolant doesn't get sucked back into the radiators, from teh resevoir?

What if the coolant doesn't get sucked back into the radiators, from teh resevoir?

Take off the radiator cap and see if the collant is covering the fins. If it is, don't worry. It should not be totally 100% full, there will be an air gap of maybe 1/2" - 2/3".

Take off the radiator cap and see if the collant is covering the fins. If it is, don't worry. It should not be totally 100% full, there will be an air gap of maybe 1/2" - 2/3".

Most coolant recovery systems will not 'recover' the coolant properly unless the rad reservoir is full to the top due to the discontinuity of the vacuum column.

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