What would make a flywheel hard to spin? Starter won't spin it.

jerryjerry05

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May 7, 2008
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18,037
Just sillycone the old one back in(if possible) then do a compression test.
The top of the piston can look great but if the rings are seized that can throw the comp off.
On the stbd. side are the port covers, you can take them off inspect the rings.
 

SemperFiDawg

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Oct 15, 2024
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Just sillycone the old one back in(if possible) then do a compression test.
The top of the piston can look great but if the rings are seized that can throw the comp off.
On the stbd. side are the port covers, you can take them off inspect the rings.
If the rings are seized it shouldn’t turn over even with the gasket cover off right? It does. It will spin with the plugs out.
 

SemperFiDawg

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Oct 15, 2024
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Reviewing older post I read it could be a bad ground so while I’m waiting on the head gasket I’m gonna clean up the engine block ground. Can’t hurt. Might help. Gasket should be in today. Will report progress if any.
 

The Force power

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Feb 3, 2019
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If the rings are seized it shouldn’t turn over even with the gasket cover off right? It does. It will spin with the plugs out.
Yes, it can turn over with seized rings & if it spins with the plugs out.....seems to me that you have a weak starter and/or bad wiring/connections/ground
 

SemperFiDawg

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Oct 15, 2024
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Yes, it can turn over with seized rings & if it spins with the plugs out.....seems to me that you have a weak starter and/or bad wiring/connections/ground
UPDATE! New thermostat and head gasket replaced today and cleaned ground terminal on engine block while I waited for them to come in. Turned ignition and she fired up first time. I'm assuming the major difference was moving the battery closer and possibly going to a larger wires to and from battery. But now I've got another problem. Will start a new thread because it's an entire separate issue.
 

SemperFiDawg

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Oct 15, 2024
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My stubbornness cost me some $$$. I couldn't do a compression test without buying a new starter so I got around to it today because after setting the timing it still ran rough. 90-32-30-90.
Lesson learned and the silver lining is I don't have to spend anymore time and money chasing another problem. Drove boat to local dealer and he's putting a Yamaha 90 SHO on it so I can be back fishing by the weekend. Now only thing I have to decide is whether I want to bring it back home and sell it as a parts motor or just let the dealer have it so I don't have to be bothered with it anymore. I'm favoring the latter because I'm about sick of looking at it.
 

jerryjerry05

Supreme Mariner
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May 7, 2008
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18,037
Usually when comp is low between the 2 middle cylinders the head gasket is the culprit, But that's over now. You'll love the new motor.

The dealer will sell the parts and charge like new prices.
Keep it and make some $$$ for yourself.
 
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