[Green-Ti]

Hi Guys,
My overheating woes continue. I have a new theory.
About 12 months ago, my heater core cracked and leakeged coolent out the back of Arkaroola. To make it home i bypaassed the heater by connecting the inlet hose to the outlet. This worked no worries and has been like this ever since and my heating issues only occurred after this. Looking through the Nissan Service manual i noted that this connection creates a kind of short circuit in the cooling system and essentially provides a path from the head to the block that bypasses the radiator. Now this may be normal depending on the way the heater works.

Does anyone know if the is a valve in the heater unit which stops coolant flowing through the core when the heater is not in use?

When changing the coolant according to the service manual you have to turn the heater ON flat out, this suggests to me that there is a valve which must be open in order to drain all of the coolant..? i could not find anything in the genuine service manual about it.

I'm going to try blocking this line and see what that does for my temps.

Cheers

 

[Roo72]

I'd reckon you'd be right. If the heater core always had hot water flowing through it you would always have hot air coming out. the heater core and the aircon evaporator are in the the same air path.

 

[petefire427]

Na mate, to my understanding they are a constant flow system through the heater core. They then use a "blend door" to control and mix the air flow. I also have a Twine heat exchanger and you don't have to put the heater on to make it work, so there would be no heater tap in the system.