And don't turn on the water to the boat before starting the engine. Either do it at the same time, or start the engine just before turning the water on (if you're using the tee or a fake alake). The entire cooling system can fill with water pretty quick and the water going to the exhaust manifolds will run right into the cylinders if there's not exhaust pressure present.
You can hydro lock the engine pretty quick if you're not careful.
Chi 190 is correct, except that you can bump it into gear for a second or 2, just don't leave it in gear, it will heat up the strut bushing.
Same with running the engine without water attached. Starting it for a couple seconds is fine, longer will burn up the raw water impeller. If you must run it for longer without water, remove the impeller or take the cover off and squirt some soap in to lube it. Then you only have to worry about shutting it off before it overheats, which takes a while on a cast iron chevy engine. (I've run small block chevies for a half hour without any coolant (demo derby!, blown water pump in BFE, etc). WOuldn't reccomend it as common practice, but it won't kill you to run it for a couple min in the driveway as long as you protect the impeller.
'06 X2 MCX
"I understand why some people may not want to do this the way I have recommended but I can't understand the death grip some people have on a toilet plunger with a hose fitting." -JimN
Last edited by Thrall; 09-29-2009 at 06:57 PM.