The ordinal 1 inch outside dia. thin wall tubing that was used
is available but hard to locate. You can search for aluminum
tubing suppliers and see what you can come up with. At the
home centers or some hardware stores with an aluminum rack
you will find 1-1/16” outside dia. thick wall tubing. I have filed
down the top of the thick wall tubing to 1” to fit inside the
exhaust manifold (don’t forget the hole for the above water
exhaust) and opened up the inside at the bottom to fit the
flange on lower unit. Its a much stronger exhaust than the fragile
tubing the motor came with.
Some time ago I found a shower curtain rod at a hardware store
that was the correct 1” thin wall tubing but it was a discontinued
item. I got the last one. This 1” thin wall tubing was also
common on aluminum folding chairs but they don’t usually have a
piece long enough for the exhaust tube.
Tubs.
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.