351 wont start!

I have trying to get a friends 81 nautique started. the boat ran fine,then when taken out of the water, the thing will turn over but wont start. The engine is a 351, and the fuel pump, coil rotor and plugs have been replaced. The compression are between 120-160psi. seems to get fuel, and I even tried to use a portable ignition . I should note that the spark seemed weak to me with the boats ignition, but with the portable it seems plenty strong, but still no start either way, not even a hiccup!!

Check your timing. It's not the easiest but you can check base timing while the engine is cranking and not running. If your timing is out the engine won't start. Also check to make sure your plugs aren't fouled and are gapped correctly.

did you spin #1 until it blows your finger out of the hole? it sounds like its 180 out.

Right on Woody! Put on the correct rotation starter and I bet it'll bust off! (wish I had a $ for every time this has happened!)

OUCH!! Cranking and cranking an engine backwards just put a huge beating on the steep sloped side of the cam lobes... If it starts, change the oil after 10 minutes and be listening for any valvetrain noise.

Look at the firing order and bump the starter with the cap off... The rotor should point to the next cylinder in the firing order sequence if it's turning the right way.

Also, the weak spark is probably from not having the proper wiring direct from the starter to the "+" side of the coil. I say this cuz you just changed the starter, and you said a remote starter made the spark better. The remote starter puts a full 12volts to the coil, but the "key on" position only puts less than 7volts to the coil. Conventional points ignition should spark the same for LH or RH rotation at cranking speed.