I finally heard back from my brother. Here is what he has to say. I hope it helps.
Maxes are not totally watertight like a boat. They have six axles sticking
out the sides, all of which will leak some. Lets see if I can make this
understandable. There are three seal points on each axle all of which can
leak. The primary seal is just the bearing (a sealed bearing). Water can
leak through the bearing if he doesn't keep them greased good. Where the
bearing fits around the shaft is just a tight fit so you can get some
leakage through there. The worst spot is between the bearing and the body.
There should be a rubber gasket in there to stop it. Check it for damage or
drying out, or if it is even there. Then there are the drain hole plugs.
They are plugged with car body plugs available at any body shop. They can
leak, especially if they are not there. Another possibility is he drove
into the water too fast and splashed it over the front or sides. Maxes do
not like rough water. They sit pretty low. And yes they feel pretty
unstable but in reality or pretty stable in the water. If you look at the
design of the tub where most of the floatation is occurring it is pretty
narrow and makes the Max rock quite a bit. However the upper part of the
tub is pretty wide and will act as outriggers. Tell him to go to the
discussion board at
www.route6x6.com if he has any more questions. Lots of
people mount bilge pumps to take care of the leakage and mount a trolling
motor if they plan to fish out of them. The tires will propel you through
the water but it is slow and inefficient.
