Seized engine MD 30 Volvo penta

[Sergy]

Hi everyone I need some advice as I am in a pickle
I have had the boat in the water over the winter, I changed the oil last fall before winterising i removed any salt water in the system by first running fresh water through the system then I drained all the water.
This is an older type MD 30 Volvo Penta which was running fine last fall. I have done all the necessary spring tune ups inserted the zincs in the oil cooler and heat exchanger, etc.
To my surprise the engine would not turn over so I suspected the Batteries as I would only hear the starter engage but the engine would not turn over. After boosting still no go. I became worried so I put socket and breaker bar on bolt head on front pulley (1” socket which I normally use when I want to adj the valves I could not bulge so the next step was to remove all the ejectors and pore oil in cylinders still no go, then I removed the valve cover and exposed the valves and push rods, I was able to spin all rods except 2 which were depressing on valve 1 Exhaust and Valve 2 Intake ( seems normal ) I put more penetrating oil in cylinders and I think next will be to ck bendix on starter as the engine feels locked wit a pin or something Maybe this is what a sized engine feels like so far if this is the case then the seizing would have to be in the Main brg., rod bearings, or cam shaft so my next move will be to pump oil into the oil galleries. I am at my wits end so if any wise mechanic out there has any advice I am all ears.

[Kettlewell]

Could be a tooth or chunk of the flywheel jamming the Bendix--I have heard of this happening. Try loosening the starter a bit or removing and see if it will turn over. When you loosen the starter the Bendix may snap back into position.

[gjordan]

I doubt that it will be your main bearings unless the crankcase filled with water after you changed the oil. Is the level correct on the dip stick? The normal culprit is moisture in a cylinder, and it doesnt take much to cause enough rust to make things not move. The best/cheapest rust breaker is a 50/50 mix of acetone and auto transmission fluid. Let it sit for a day and try to move the crank, repeat as needed. I would recommend taking a lead hammer and make sure all of the valves will move before you start turning things. If there is moisture in a cylinder, you may have a stuck valve, which will cause a bent pushrod if you break the engine free, but have not freed up the valve. Just reread your post, and agree that removing the starter would be the first step. Then go for the liquid in the cylinder. Another trick that I have used with some success is to rent a steam cleaner and plumb it into the cooling system, and heat and then cool the engine. The expansion and contraction of the metals will sometimes break up the rust and get it turning. Good luck with it and keep us posted as to your results.____Grant.

[Sergy]

Thanks Grant

[sailful]

Hi Sergy: Any update on your issues?
Thanks
Stan