Check starter wiring connections and charge status of battery(ies). The connections on the actual starter can sometimes look clean and tight, but still have some corrosion. Unfortunately most inboard starters are difficult to reach, unless you have one of the rare engines with a top rear mount starter. Use a long extension on a socket wrench and loosen the nuts (much easier if you do not have to completely remove the nuts), carefully rotate the wire terminals, apply some lubricant and re-tighten the nuts. You may have to remove the starter to check the connections and starter. There are previous posts about using a short section of all thread rod to facilitate starter removal and re-installation.Good morning Gentlemen,
I am back at it. Family issue pushed back the work. Tried to start boat with good battery and jumped it with a running silverado. Only got a thunk sound from the starter. Pulled plugs, shot WD40 into each cylinder. Will try again in a few hours. Oil looks good in engine and velvet drive. I want to convert this to raw water cool and add a kicker for when the 302 finally dies. I tried to turn the motor with a ratchet on front nut; wouldn't budge.
Plenty of wet foam under the floor. Will break it up with a spade bit on a drill and vacuum it out. Probably will fill void with empty soda bottles and expanding foam.
Please chime in.
If you are concerned that the engine has locked up, disconnect ignition wire and belts, and attempt to slightly rotate crankshaft (correct rotation) with a large socket and breaker bar.