Getting Hot

[WoodI]

Hi there, I'm new to this forum. I have the 4 litre SC400. Now it is getting hot. Almost like the thermostat is sticking. It gets really hot and the heater blows cool air. Then , as if an air bubble just yet loose, the heater will bow warm air and the temp will come down. Not all the way, but down to a safer level. Do I have to pull that bung on top of the thermostat to bleed an air lock?

[UCF3]

Woody:

Welcome to the forum. there are a number of possible scenario you should try.

1) see if there are any loose leaves blocking the cabin air duct (between windshield and bonnet).

2) there is a control arm/latch that controls your heater and cooler from coming into the cabin. the door and latch is located on the passenger-side of the firewall. move the temp settings to max cold and then max hot to see if the door is openning and closing.

3) the Final one is what you're doing right now. a coolant flush will help, but remember to use the Toyota long-life version and use the machine. When the body shop did mine and i paid for them to flush the system they must have not used the machine beucase the engine is warming up again.

Let us know how it goes.