Coolant overflowing the overflow container.
SEE PICTURES ON PAGE TWO OF THE THREAD. SEE PICTURES ON PAGE TWO OF THE THREAD. 2016 Toyota Sienna with 15,000 miles. Coolant has appeared on TOP of the overflow tank since the van was new. I...
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The bottle is nothing more than a visual expansion tank. Consequently, if the bottle is properly filled when the engine is cold and overflows when hot, you have something displacing the coolant in the motor and pushing the level up. I lean toward a perforated head gasket but it could also be the water pump sucking in air from the weep hole.
Sure way to find out the system cold to the correct pressure and do some observation around the motor without it running first, to see if coolant appears anywhere externally and the start and tun the motor and observe what the coolant in the expansion bottle does.
If you have a perforated head gasket it will rise and when cold and the system is at negative pressure, sucking coolant into a combustion chamber and burning it, don't mean you'll see it at the tailpipe because your emissions hardware will burn it off. Only way to be sure at the tailpipe is to do a emissions test. The test will show if any coolant is in the exhaust gas flow.
I'll put my money on a perforated head gasket. Did you take it to a Dealer or the ,local grease monkey?
Sure way to find out the system cold to the correct pressure and do some observation around the motor without it running first, to see if coolant appears anywhere externally and the start and tun the motor and observe what the coolant in the expansion bottle does.
If you have a perforated head gasket it will rise and when cold and the system is at negative pressure, sucking coolant into a combustion chamber and burning it, don't mean you'll see it at the tailpipe because your emissions hardware will burn it off. Only way to be sure at the tailpipe is to do a emissions test. The test will show if any coolant is in the exhaust gas flow.
I'll put my money on a perforated head gasket. Did you take it to a Dealer or the ,local grease monkey?
