Hello all. I recently had the 3.5L engine on my 2007 Dodge Magnum SXT hydrolock. Simple explanation, I didnt realize the puddle I was driving through at a low speed (slow enough for a fast walk) was so deep. You can figure out rest, Anyway, since then I brought the car home, I removed the intake plenum along with the coil packs and spark plugs to try to crank the engine to purge the engine of water inside. No such luck. When I turned the key, you can hear a click as though the starter is trying to engage, but the engine wont crank. I then manually vacuumed the water out with shop vac but the engine still won't crank and turn over. Does anyone have any ideas of anything I might be missing to get the engine to turn over or do I have the worst case scenario and the engine is scrap? Any input is greatly appreciated!

 

You may have internal engine damage, Can you manually turn the crank via balencer bolt in either direction? If not drop the pan and see what's going on.

 

I have done several hydrolocked engines. Usually a rod breaks or bends and binds things up. Unless it cracks the cylinder wall, its fixable. If you have a borescope, look in each cylinder to see if anything looks awry. Water in the cylinder, broken parts. Next, drop the oil pan. This should allow you access to check out all of the rods and pistons from the bottom. It'll be obvious as to which one(s) are bad.
You'll have to remove the respective heads so you can remove the bad pistons. Put thin rubber hose over the rod bolts to keep from scratching the crank. Either buy a new rod, piston, rings and bearings or pick up a used one on Ebay. I've used several without any problems. You just need to know what to look for when buying used. Hone the cylinders lightly to remove any surface irregularities and light rust if any. You may have some light dings and that's okay as long as they're minor. You're just trying to true/smooth up the surface. A minute or two with the hone is usually good enough. Use transmission fluid or WD-40 as a lube while honing. Be sure to wipe clean when done.
I've done a 2007 5.7 with a broken rod and a 2011 3.6 with a twisted rod and piston. Both run and drive great after fixing.