Ok, well not hot enough to burn the 4runner down, but pretty damn warm. I'm guessing it's the coolant lines for the rear heater that are the culprit. I have both the rear fan and the "heat selector" both off. Should it still be circulating coolant through the rear heater? Is there a seperate valve for the coolant going to the rear heater?

Thanks,

Casey

 

The rear heater has a seperate heater core that coolant flows through. It should be getting warm. Its perfectly normal. the only "valve" is in the rear heater core itself, so it will always get warm.

 

The valve in the rear heater should shut off the coolant flow if the valve is working and fully opens and closes. At least that is the way it was on my '85 rear console.

 

Yes, but the coolant flow up to that valve should be warm, which will create some heat in the center console area.

 

With the valve closed, there is (or should be) no flow. Being several feet back from and a foot or two below the source of coolant (at the firewall heater control valve) it is unlikely that you would get much heat conducted/convected back through the non-flowing coolant in the inlet tube. Note that the coolant circuit it an inlet line, a valve and the return line. If the inlet line is blocked by the valve, no coolant flows in or out. The valve is a simple open or closed device, it has no bypass feature.

But yes, if the valve in the rear heater is not fully closed then you could get some flow and resultant heat build up. You will get a fair bit of heat radiating/convecting up from the transfer case which sits just below the console. I know mine gets pretty warm (dual cases put out more heat) and I no longer have a rear heater in the console.

 

Ok, So the valve for the rear heater is at the rear heater core? I wanted to make sure before I tore into it just to find out the valve was located at the firewall. i think if the valve were working the flow of coolant would stop and eventually cool. It must not be fulling closing in my case as the console stays hot.

I thought that it might be the T-case or the Tranny but I dont feel any heat on the carpet at the base of the console. Just on the sides between the seats and the console on both driver and passenger sides.

 

Yes, the valve is in the rear heater, it is what the lever that controls the temperature is connected to.

One simple test would be to bypass the heater lines under the cab (i.e. connect the inlet to the outlet line) and if the heat goes away, then the valve may be at fault.