FZJ80 rear heater hoses

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How’s this holding up? I was messing with mine cutting with a dremel and nicked a hardline 🤦🏼. Really not wanting to replace them all. They look super corroded so I thought about removing the rear heater or doing what you did.
I kept my rear heater, you should have read my post about removing the stock clamps with a spring tool hook. U can order these gates formed hose if you need to bypass the rear. Order qty 2

Can anyone confirm where both lines from the rear heater end up in the engine bay?

I'm running the green stripe all the way (bypassing the metal/rubber routing, but NOT deleting).

It seems like the rear heater return comes into the 90 degree of the 'T' connector on the passenger side (US) of the engine bay and the return from the main heater core is the in-line of the 'T'.

Does the other hose that feeds the rear heater core run directly to the heater valve? I doesn't look like this rear heater was ever 'bypassed' but I have some empty metal hose terminations on the drivers side. I've looked and studied the videos and diagrams, and I really appreciate all the efforts that have been made, but I've love to see the tutorial that follows the flow of coolant, and explains how the rear heater diagram interfaces with the main cooling system diagram- I can't quite tell how they connect based on the diagram.
The rear water heater hoses are 1/2" ID and start from the firewall.

The right side comes off the bottom of the T connection, not quite a 90' bend to a hard pipe bolted to the firewall. That hose is not available as a separate part as it comes already attached (when the entire assembly is purchased) to the first set of hard lines seen in the diagrams above.

The second hose on the firewall for the rear water heater is located about in the middle of the firewall, you can see it if you stand by the right fender on a stool and look close the rear of the valve cover and firewall.

That short straight 1/2' hose section comes off the bottom pipe of a black pipe assembly that has two pipes coming off the lower section, one pipe is for 5/8" hose (main heater pipe coming out of the firewall) and the other is for the rear heater circuit which is a 1/2" hose which goes to a 1/2" hard line (see diagram above). Again, that 1/2" hose is not available as a separate Toyota part however it's straight so Gates Greenstripe will work. Or, there is a water heater circuit hose from a 100 series that can be cut to get both rear 1/2" heater hose sections: the ~90' hose and the straight section of hose if you want to use OEM hose that is.

Clear as Mud?

Try some searches for rear heater hoses firewall etc and you'll get some hits, been discussed.
Thanks for the reply- I found one of the YouTube videos to be the best, at actually showing the input versus return to the front and rear heater cores.

I plan to edit the diagram to highlight where the rear connects in- just haven’t done it yet. I think to replace the inflow requires removal of the valve assembly and possibly the intake too.

I bypassed the return with green stripe, but just did small splice on the input to the rear.

Hopefully will edit this post soon to be more helpful. You guys are great!

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