Unable to turn motor by hand with spark plugs removed

Hello, my first time on forum, sure could appreciate some experienced advice. After he passed one year ago, I recently purchased my Father in law's 1985 19' Bayliner Capri Cuddy with the four cylinder AQ125. Background: Don was meticulous with his boat, always garaged, maintained. Just before he passed, I know he had the boat serviced because he had a trip planned the next month. I took it to the lake for a shakedown cruise; it started immediately, always been cold-blooded so warmed it up and idled out slowly. It sounded great, idled for about five minutes in gear while checking oil pressure and temp. Everything good, so spent the next hour running at different speeds on step, then idled, always watching the gauges. Very happy with everything, I was on step at about 4000 rpm when my wife and I heard a high squeally sound. I throttled down into neutral and the engine died; Checked under the doghouse and noticed part of the 1" thick insulation blanket had come loose near the alternator. Reattached it and expected that was the trouble, though couldn't see any marks on the silver foil insulation.Wouldn't start, just one click each time I turned the key. Checked connections, then motored in with the kicker. At my shop, I tested the batteries, voltage at the solenoid, cleaned all connections, tried her with the muffs on, but the engine turned maybe half a turn, then click, each time I keyed it, then turned fractionally, all the while sounding scratchy. Then nothing but a click. Pulled the starter and found metal shavings at the flywheel.Pulled the spark plugs and tried to turn the main pulley by hand. Won't budge. Tried with a deep socket and a short wrench (no cheater pipe), still would not budge. Hoping for some kind of miracle...? Any suggestions would help, I'm really bummed and I need a clear plan to move forward.

it does not sound like good news, is th estarter still out of the boat? try getting a large screwdriver of prybar on the flywheel tooth and se if you can get the engine to move byprying it against the bellhousing. it should turn unles the engine is locked up, which sounds like it did. you most likely need to pull the motor to investigate more.

I was on step at about 4000 rpm when my wife and I heard a high squeally sound.

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The above comment, plus the fact that you are now not able to turn the crankshaft, would indicate that something has locked the engine up.
I would pull it and further investigate.

Thanks stang32, I had tried turning the flywheel with no luck, although I didn't use a lot of force or a very large screwdriver. I don't have enough experience to know how much is too much, but this engine should turn, and it does not. Back to the machine shed, I guess, Thank you for your comment!

Okay RicardoMarine, I at least feel confident that I have a real problem. I appreciate the help. Taking a motor apart is out of my league, so I'll be calling a shop and hoping it isn't priced more than the boat is worth.

I'm not sure if this applies to your engine but on mine I have to be sure to turn it in the same direction that it normally rotates otherwise you may be fighting the water pump impeller and do damage to it.

Froze tight in either direction, and the belt will slip anyway. The mechanic is going to take over and likely pull the outdrive and see if the problem is there. He says one possibility is seized bearings on the short shaft to the outdrive. Never thought I'd be hoping for a seized bearing... I'll post his evaluation as soon as I get it.

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lcwillislll said:

Froze tight in either direction,
May we assume that by "Froze tight" you mean that the crankshaft won't budge one bit in either direction?
That is what I'm reading!

The mechanic is going to take over and likely pull the outdrive and see if the problem is there. He says one possibility is seized bearings on the short shaft to the outdrive.
OK... hold on!
This mechanic is not understanding the AQ series stern drive system.
What he's calling a "short shaft" is a PDS.... (primary drive shaft), and the drive coupler's center hub is spring cushioned.
If either the PDS bearing or the transmission (upper gear unit) is locked up, the engine will still rock back and forth a bit in either direction.
Plus, if the PDS bearing and/or transmission was locked up, we would pull the transmission ONLY....... not the entire stern drive.

If the crankshaft will not rock back and forth at all, you have engine problem, not a PDS bearing or transmission problem.

NOTE: When removing this engine, the stern drive does not need to be removed.
You will disconnect the engine from the flywheel cover (bell housing in the auto world), remove the lag bolts from the side mounts, and pull it out.


Hopefully I caught you in time.

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Thanks RicardoMarine, Yes you caught me in time, yes there is no movement either way that I can detect, and I sadly mischaracterized what the mechanic said. I asked him what his steps would be without leading with anything, and he said after looking it over he would pull the motor and the oil pan so he could get to the flywheel and something else I can't remember, which is in line with yours and stang32's advice.

RicardoMarine, stang32, motor pulled and a broken spacer from starter jammed tight to teeth of flywheel and the side of the bell housing. Coulda been so worse. Here's a pic of bunk rebuilt bosch starter with cracked spacer, another piece jammed into the starter housing at about 11 o'clock on the pic. No rebuilt starter for me on this boat. Glad it happened on a quiet lake shakedown cruise and not in the middle of the Columbia River bar. Thanks for your advice!

lcwillislll said:

RicardoMarine, stang32, motor pulled and a broken spacer from starter jammed tight to teeth of flywheel and the side of the bell housing. Coulda been so worse. Here's a pic of bunk rebuilt bosch starter with cracked spacer, another piece jammed into the starter housing at about 11 o'clock on the pic. No rebuilt starter for me on this boat. Glad it happened on a quiet lake shakedown cruise and not in the middle of the Columbia River bar. Thanks for your advice!
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well, like you said, could have been worse, shame you didnt inspect the starter when you pulled it to accss the flywheel.

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lcwillislll said:

RicardoMarine, stang32, motor pulled and a broken spacer from starter jammed tight to teeth of flywheel and the side of the bell housing. Coulda been so worse. Here's a pic of bunk rebuilt bosch starter with cracked spacer, another piece jammed into the starter housing at about 11 o'clock on the pic. No rebuilt starter for me on this boat. Glad it happened on a quiet lake shakedown cruise and not in the middle of the Columbia River bar. Thanks for your advice!
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Today, you can find a HTGR/PMGR starter motor for these engines.
Much faster cranking than with the non-gear reduction starter motors.