I have a 1999 4Runner with a rear seat heater that is fed with coolant. One of the lines has started leaking. I have a service appointment on 9/1/22 but it’s dripping a little each night on my driveway. I wrapped the drip point with an absorbent towel and must have dislodged some crust, making the leak worse.

Can I pinch off the line while I wait to get it in the shop? It’s my daily driver and I don’t need the rear heater to function. Does that line need to flow fluid for the rest of the coolant system to work properly?

Thanks,

Erich

 

Since we aren’t in cold weather months yet. The easiest way to bypass the rear heat circuit is up in the engine compartment. Along the firewall, about halfway between the center and the passenger side, you’ll find 2 metal hard lines attached to the firewall that disappears down, and have a 90* bend point forward connected to 2 rubber lines about 3/8” in diameter.

Here you can follow the 2 rubber lines and figure out which is easier to disconnect on the engine side. You are going to undo both lines, but on different sides. I’ll try to explain this without the help of pictures.

you have 2 rubber lines, A and B. They are connected at the firewall, Af and Bf, and at the engine Ae and Be. Let’s say Be connection is the easiest one to find. You are going to disconnect Af and Be connections, then run Af to where Be was connected, and run Be where Af was connected. Now you should have the 2 rubber lines connected as a loop at the firewall and as a loop at the engine. Line B should be connected Bf and Af, and line A should be connected Ae and Be.


Now for long term repairs. Those hard lines for the rear heat are expensive and tough to get into place. The easier way is to buy like 20’ of rubber line, connect it to the 2 fittings at the engine, fish it down along the original meta lines, and connect it to the 2 fittings under the passenger seat. Essentially replacing the metal lines with rubber.

 

Great advice!!

Thanks,

Erich