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Help: Engine won’t crank or turn by hand. Seized?

Travise

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Today my clean out plug blew but the lid didn’t pop so I kept driving for a min before realizing the problem.

Then after I put plug back in it wouldn’t crank. Tried all the usual suspects: lanyard, clean out hatch switch, battery connection, fuse. Other engine started fine.

Drove back home with one motor and tested the starter with jumper cables when I got back. It made a clicking noise like it was trying to work but couldn’t turn.

Then I took out the spark plugs and tried to crank the engine by hand. It wouldn’t budge. I could turn the other engine fine (slowly). I read this means the engine is seized but that’s usually after you haven’t driven for a while. Did water get in the engine when I didn’t have the clean out plug in? What do I do???
 
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drewkaree

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From what you related, those two things don't sound related. The cleanout plugs simply let you clear the impellers, and even if the hatch switch was bad, it shouldn't cause the issues you're describing. Someone else can/will chime in, but don't throw in the towel just yet
 

WREKS

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Some debris may be jamming the impeller. Inspect closely and carefully!
 

mkbcaptain

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mkbcaptain

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Have you pulled the spark plugs and tried cranking? Maybe pull the pump off and make sure everything is straight and not seized up.
 

Travise

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Thanks for the help.

Yeah I pulled the spark plugs and tried cranking by hand but wouldn’t move. I felt around the impeller but didn’t see or feel anything amiss.

By pull the pump off do you mean the entire unit hooked to the back of the boat? Do I first take off the cover that slides down for reverse? I just unhook the 4 bolts or do I need to take off the hoses attached to it to get it off? It’s on a boat lift so I’ll be operating on a paddle board 😀. Cants drop anything. Here’s a pic:
 

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drewkaree

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It’s on a boat lift so I’ll be operating on a paddle board 😀. Cants drop anything.
This sounds like an expensive experience about to happen. Make sure to get this on video, I'll hold your beer for you! LOL

If you seriously don't have any option, at the very least use a lily pad float or something like that. Worst case scenario, go to Home Depot and get a sheet of XPS insulation (the thick rigid pink foam that comes in sheets like plywood). Trim the sides of it, and stick it to the topside to make yourself a tray that you can operate over so you can hopefully contain anything that you WILL drop.
 

WREKS

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You may be able to access the impeller shaft by going underneath the boat. Try rotating the shaft with a vise grip!
 

the MfM

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Either you have really bad luck and seized an engine at the exact moment the plug blew out... OR water get in the engine bay and did some damage. Hopefully the water didn’t make it into the engine.

I’d start by making sure the battery cables and engine grounds are clean and well connected.
 

Travise

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Ok I took the boat out of the water and removed the jet and impeller. The impeller spins fine when off the boat. I tried hand cranking it again with the impeller off and spark plugs out it still won’t hardly move. It barely moves 1mm back and forth but won’t spin like the other side.

Is there anything else I should try or is it time to take it to a mechanic? I read something that “hydro lock” is more salvageable than other seize types. What does that mean? How much would a new engine cost if it comes to that? Any other ideas?

@HELP
 

bronze_10

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That doesn't sound good. Hydro lock is when water enters the cylinder. Water doesn't compress like air. Often times it will bend a connecting rod. But alot of times it will still turn over after the pressure is released i.e. removing the plug. Unless its real bad. This is starting to sound expensive. Unfortunately.
 
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