georgeM

Heater hose

Howdy y'all, so I am merely a few weeks into owning a Toyota truck. Depending upon who you ask, it's a 1979 or 1980 with a 20R.

And I have two questions in regards to coolant lines- particularly those running to and from the heater core.

The previous owner capped the hose that exits the engine on the passenger side, and goes to the heater core. So this hose is not hooked up to the HC at all. First question is thus, would this be the supply line to the heater core?

Another hose, which is attached to the heater core port on the firewall snakes it's way between the master cylinder and the engine, goes to a bracket on the drivers side fender, and slightly beyond where it too is capped off. Second question, where the heck does this hose go? I can't for the life of me find a nipple where it would attach. My hypothesis is that, perhaps, I am running with a non stock radiator, and perhaps this hose is intended to attach to a port near the lower radiator hose. Could that be right?

I tried searching the forums and could really find the info I'm after, so may I offer an apology up front is this is a common question y'all have to assert with some frequency.˟

Any help would be appreciated.˟

Thanks and cheers,

GeorgeM

LittleBeast

no i dont think that one goes back to the radiator and yes i think that other one might be a supply line

Sensei

The passenger side hose should connect to the intake manifold while the driver's side should connect to the backside of the water pump ???
Check out TTORA or Pirate 4x4 sites. They have FSM's ( factory service manual) that you can download.

83rustbucket

Sounds similar to my 83 22R. My heater core is all connected and used to work, but I believe it to be clogged or the flow valve is not operating properly. I want to figure out which heater core hose is the inlet and which is the outlet but have not found any information regarding the direction of coolant flow.

I think what Sensei says is correct. I'm going from memory right now but, on my engine, there is one hose that connects to the intake manifold behind the thermostat and runs to the flow valve and then into the firewall. Another hose runs as you described from the firewall to a bracket on the driver's side fender, and then connects to the radiator lower hose.

I couldn't find much more info in Haynes or FSM.

That may or may not help, I can't remember all the specifics but I can post pics tomorrow if you are interested.

And if anyone knows for sure which HC hose goes in and which is out, that would help me. I'm going to run water through both sides of the HC anyway but still want to know where to put a T for backflushing the whole system.

suncomb1

One hose connects to a tube piece under the intake manifold. The tube piece is connected to a flange on the right side of the timing cover / water pump. The second hose goes around the rear portion of the engine and connects to a tube bib located on the driver's side fenderwell where the two lower radiator hoses are connected.