Spins without spark plugs. Wont spin with plugs installed. 96 SLP 112 HP

[Shoumard]

My 1996 Johnson 112hp slp was froze up/ stiff. A little lube( BP BLASTER) in the cylinders and it started to turn freely with the pull rope. I can spin the unit with a pull rope and or the starter with no problems with out he plugs inserted. When the plugs are installed I can not get the starter to turn the flywheel and or pull with the rope What is going on? Stuck valves? What to do? Is there a FOGGER that would free everything?

I had light brown fluid in the cylinders, I think there is water in the tank from a leak in a gasket . I switched to a three gallon portable tank with new gas,

 

[racerone]

No valves on this motor to cause those problems.---------Can you turn the flywheel slowly by hand for one complete revolution ??-------Wrench on the flywheel nut and see if it can be turned over that way ?

 

[pn]

i guess your directly connecting voltage to the starter, or starter solenoid or just turning the key?, if directly to starter then, starters bad if not then you'll have to check your whole circuit, (kill switch lanyard/ in neutral) check all connections and wires by feeling them, if they get hot you've got resistance. good luck.

 

[gm280]

Are you certain the plugs are the correct ones and not too long hitting the pistons? Because when you state that plugs out it spins and plugs in it won't move...?

 

[boobie]

Have your battery load tested and check all your battery cable connections.

 

[steelespike]

If there is a lot of lube added to the cylinders it may be so much that it won't compress.
Pull the plugs and lay it on its back so anything in the cylinders can drain.
Or try spinning it good with the the starter with the plugs out.

 

[emdsapmgr]

Try jumping the starter with a set of automotive jumper cables to a known strong battery. If the starter cranks normal rpm's it's not the starter. Then check the starter solenoid. If the internal contacts are burned (happens with age) it may not be transferring the proper current to the starter.

 

[andrewdouv]

Had the same issue last week. First I suspected my batter, so I parked my running truck next to the boat, grounded on the outboards powerhead and touched the starter. Still cranked very slowly. Hopeless. Then I checked for bad connections, etc and didn't see anything wrong. Tried another starter from my part motor, no luck. Finally I went back to suspecting battery and tried a brand spanking new battery and it started up fine.

TLDR; Had the same problem, in my case the battery was to blame. How old is your battery? Was it stored in the cold during the winter? Did you have it on a trickle charge inside?

 

[emdsapmgr]

Sounds like your original outboard battery may have had a bad cell.