Mariner 30A Flywheel won't turn

[Bullie]

I am working on a Mariner 30A for a fellow. He said it wouldn't run and he thought that maybe it had some bad gas in it. Compression was 120/124 and spark jumped 7/16. I pulled off the fuel filter and it had a little water in it. Tonight I pulled the carb and the bowl was about half full of water. I cleaned it and reinstalled. Now the weird part. It won't turn over. Maybe a half inch of rotation. I pulled the plugs and tried again. Nothing. Any ideas?

 

[JonBrown]

Hello Bullie,
I have had a Mariner 30A and 30 Kick my butt a few times in the old days. Although it seems cannot be locked up. To check under the flywheel to see if there is corrosion? May lock it up. Just a idea. Can you see into the cylinders? Are they clear, no scratches and etc. If all looks clear then definitely a bearing , usually the top one under the flywheel may have locked. Although I never saw one turn over on a compression test and just lock up. There may been a lot of moisture ran through it. It will not burn it and it will be in the crankcase. I hope this vague answer helps.
Thanks, Jon

 

[Bullie]

I did try to look in the cylinders. Can't see much of the walls. The weird part was that we pulled it for the compression test about 10 days ago but now it won't budge at all. I am lost on this one.

 

[Texasmark]

How are you attempting to turn it? Grasping the flywheel by hand with the plugs out? When you say none at all, does that mean 0.00.00 degrees/min/sec? Or does that mean a few seconds maybe. If the latter, look in the spark plug hole and see if one of the pistons is trying to move and maybe the other isn't. Would indicate a stuck ring. In that case and maybe anyway, pull the exhaust manifold water jacket and cover and have a look at he side of the pistons via the exhaust ports. Giving everything a good dose of PB blaster wouldn't hurt, through the carb, spark plug holes and exhaust ports. Let it soak and try again. May have to pull the lower unit to ensure it isn't locked up and keeping the powerhead from turning.

 

[Bullie]

Texasmark, it had a little bit of movement I guess. I rocked it back and forth until I could turn it by grasping the flywheel with my hands. I tried that before I saw your reply and used fogging oil instead of PB Blaster. It was difficult but it would turn. I will pull the exhaust cover as you suggested and have a look around.

 

[Texasmark]

Since it is "cracked" I'd say that your problem is rings stuck to the cylinders and if your compression tests were done without any lube in the cylinders you may have scored them resulting in your present condition. Pull your exhaust manifold plate and water jacket cover under it and look at the exhaust ports of your cylinders. You can see if scoring is present and you can squirt some PB blaster through the ports into more of the ring-cylinder interface.

 

[Bullie]

I haven't had the opportunity to do any work on the motor but I walked by and tried the flywheel and it wouldn't turn again. Going on a camping/fishing trip for a few days. Will update when I have a chance to pull the cover off.

 

[Bullie]

I used a good dose of PB Blaster and Fogging Oil on this motor like you suggested. Next time I tried it moved well and started right up. Dialed the carb in for the kid that owns it and he is chasing fish again. Thanks a lot for the help.