"Hunter..... That depends on e
"Hunter..... That depends on exactly how hot the previous owner ran that engine, and just how good it ran before he ran aground.
Also.... If you're saying that sand exists IN THE WATER PASSAGEWAYS that surround the cylinder walls, the following reply will pertain. BUT if you're saying that sand actually got INTO THE CYLINDERS WITH THE PISTONS while the engine was running, scrap the engine and ignore the following reply.
Check the bolts, screws etc that attach the coils, pack, etc etc... whatever bolts you can get at. If they're all loose, the engine was pretty hot. However, that doesn't mean the engine is shot.
If it was a good engine previously, and excepting loose bolts, none of the engine components have melted down... the initial work would be to remove the lower unit so that you can install a new water pump. Now, with the lower unit off, you can use a air compressor to blow out the sand from the engine's water passageways and the inlet water tube(s) that normally slide into the lower unit. Getting rid of that sand, if it's a bad as you say, might take some time.
Use extreme caution that you DO NOT allow that sand to enter the piston and cylinder wall areas. Besides doing damage to the cylinder walls, the intake and exhaust ports would allow access to the wrist pin, connecting rod, and main bearing areas etc. Plug those cylinders holes properly!
The initial investment (or $$gamble$$) would be the price of a new water pump assy and two head gaskets. New spark plugs of course. If the engine now runs as it did before, you've come out ahead. If not, you can always part it out.
Whether or not you decide to go the above route is a judgement call you'll need to make.
Joe (30+ Years With OMC)"
