Originally Posted by Mattbzn
But it’s a rear-engine bus, so wouldn’t removing the heater hoses (even looped) disable all heating, including the defrost?
In my 2008 RE300 that is the case. I can only assume so for the 2006. The heaters are run in series so closing the valves or putting a loop in at the engine bay would cost you the function of all heaters, including the defroster, on the bus. I don't know if you've ever driven a vehicle without a defroster but I have, and you don't want to. Especially with a vehicle as large as a bus, it would be very unsafe.
I'd replace the damaged hose first, or patch it with a hose connector. Cut out the damaged section of hose, in your case a 1 inch section where the screw hole is, and install a hose connector with hose clamps. Hole fixed.
And then assuming the rest is exactly the same as mine:
In order to delete the midship heater, go under the bus where the side E-door is and go between the frame rails. You should see the blue heater hoses, yours are pretty dirty in the engine bay, but trust me, they're blue. At that point on the bus there should be a break in the heater hose line with some 90 degree metal hose connectors, those create a branch for the midship heater and go towards the E-door. Take out those 90 degree hose connectors and install a straight hose connector with some hose clamps to bypass that branch. Now you should have a continuous run of heater hose from the rear of the bus to the front of the bus.
As far as where to get those straight hose connectors. Check the section of hose you're removing for the midship heater, mine had three separate hose connectors in it. It's clear to me that they made that branch for the midship heater out of spare hose, and had to use a lot of connectors to make it work. If you aren't that luckily they sell them at pretty much every home improvement or plumbing store.