Stuck engine following cranking last month

[Sherrysild]

My Merc MAG350MPI does not turn over after a few weeks. We cranked the engine, but without start due to poor battery in July. It has been two years in a cold and damp boathouse since last time it started. Rust in cylinders? Stuck pistons? How do I go about loosening the stuck engine? Is it at all possible? Thanks, Are

 

[Rick Stephens]

First thing pull the plugs and see what you got in there. Rusty? Squirt some oil in there, I'd use Marvell Mystery Oil to break loose a little rust.

Don't use the crankshaft nose bolt to try and turn things. Pull the three pulley bolts off the harmonic balancer and replace them with ones a little longer . Use a bar on those to try and turn it. Work it back and forth a bit.

 

[tpenfield]

Since it turned over a few weeks ago, if probably is not all that much stuck. As Rick mentioned remove the spark plugs and see if you can get the engine to turn over.

 

[Scott Danforth]

if you had water in the bores and it sat for a month, the motor is toast

especially if you boat in salt water.

first thing to do is to pull the plugs if any are wet, pull the motor

 

[wahlejim]

Step 1: Look for water after pulling plugs. If water is present, do as others have said.

Step 2: If no water is present, clean your electrical connections. Damp storage does not play well with electronics. Shiny clean metal from the battery to the starter to the engine ground and all connections in between. You can have a brand new top of the line battery fully charged, but if the connections are not great, it will act like a 10 year old battery that barely holds a charge.