Seized Motor

dmskibba

Recruit
Joined
Aug 7, 2002
Messages
1
I have a 1980 (approx) 28 HP Johnson Motor with rope start. I have not run it for the last two years. It has been stored under cover outdoors (in New Hampshire). It ran fine the last time it was used.<br /><br />I want to use it now and I (rather optimistically) assumed that if I put in new plugs along with a squirt or two of oil into the cylinder, everything would be fine.<br /><br />I cannot start it because I cannot pull the starter rope. With the cover off, I can move the flywheel with a pry bar.<br /><br />My question is whether this is a situation I can rectify or should I just take it in and have it fixed? I am comfortable with working on it up to the point of pulling the head.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: Seized Motor

Dboy..... If you can (by hand) move that flywheel the slightest bit back and forth, that would indicate that the binding is at the piston area, and that the crankshaft and its associated bearings are okay.<br /><br />If this is the case, tilt the engine and spray in some OMC Engine Tuner, then let it sit overnight. That should help somewhat whereas you'll be able to eventually get it to turn over.<br /><br />Since it's frozen, you've nothing to lose by trying to free it. If all else fails, then tear it down. Good Luck.....<br /><br />Oh, one more thing.... since the engine has been sitting for some time, be prepared to remove, clean, and rebuilt the carburetor as it is without a doubt, gummed and fouled.
 

harrison20002

Petty Officer 1st Class
Joined
Aug 26, 2001
Messages
222
Re: Seized Motor

Dboy: I learned this when I first discovered this forum.<br /><br />Pull the head[be careful not to twist off head bolts], Buy some PB Blaster [much better than WD-40 and most parts houses carry it], Spray all around the pistons and let it soak overnight. Take a wooden block and tap on top of the piston until it moves a little. Then repeat with the other piston. During this time keep wet with the Blaster.<br /><br />When you have it freed up inspect the cylinder walls. If only slightly scored you can dress them up with very fine steel wool.<br /><br />I had 9.9 that was "frozen" and now mine runs great. I hope this helps a little. Happy Boating, Hal
 
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