Shallow ridin!
Like Karl says, the engines in your boat, the 1503 4-TEC engines are 4 stroke and have a closed loop cooling system. But the cooler (radiator) that is used in exchanging heat is built into the ride plate. So, depending on the strength of that ride plate, striking the bottom may cause damage to it.
As for picking up sand....this is a big problem with PWC/watercraft owners who love to ride the surf. My boat's original owner only used it at the beach. When I removed the head cover, I found quite a bit of sand that had settled in the bottom of the jugs.....
I've thought about putting one of those water filters on it, with the glass cover, so that I can see the amount of sand being built up in it. That way, riding in a sandy environment would keep the small granules of sand from getting trapped in the orifices of the cooling system.
The inlet cooling hoses are about 1/2" in size. If you think you might like to mount some type of clear filter with a stainless screen, you'd need one with a larger flow, like 1" in and out. Then, use reducers to drop your sizes back to your cooling water hose size. This will give you piece of mind that your flow rates won't be affected until the strainer basket begins to take on a few cups of sand. If you check it after every outing, you would think it to work pretty good............
It's just something I've pondered in doing to keep the sand and debris out of my cooling system. I have't actually done it yet.
Good luck!..........
Oh BTW, although you'd be able to run on shallow draft, if you let the boat off plane, you'd have one hell of a time getting it off the sand bar....:ack:
