Tohatsu 25 water in cylinder

[Ken matlock]

@2000 25 hp 2 cylinder 2 stroke. Hasn't ran in 4 years. Removed and cleaned carb. Checked spark all ok. New fuel and it fired up. Ran ruff. Removed top spark plug started engine while on muffs and noticed water blowing out of spark plug hole. Please tell me it could be something simple. I'm not a outboard mechanic. Not even a ok shade tree mechanic. While engine was running I noticed a water leak from a gasket on top of engine. I tightened both bolts and it quit leaking. At least on the outside of motor. I'm not sure what is under plate or gasket. I do not have a Manuel on engine since I just got it. I have pics but web site keeps kicking them back. Thanks for any help or advise

 

[Sea Rider]

Welcome to Iboats,

Could be water condensation due to long storage. Remove both plugs, spray a small portion of 50:1 fuel/oil mixture into combustion chambers, pull cord several times to clean water leftovers. The small upper part you described is the thermostat, just adjust both side bolts tight to seal small gasket under lid, don't over tighten. Better install a new set of spark plugs gaped tight to 1.0 mm for top engine performance.

Happy Boating

 

[Ken matlock]

Thanks for the response. I have replaced spark plugs and ran a gallon or so of fuel threw it in the yard on muffs. water is for sure entering cylinder somewhere. I ran it for a minute or so with plug out and water or more than steam was coming out. Water drops getting blown out would be my best description. Plug is firing but looks new. After a hour of idle an a little throttle in the yard. Bottom plug looks like a hour of use. Thanks again for ur info and help

 

[Sea Rider]

Being a 16 year oldie OB, would replace head gasket ASAP, there's water comming in through head water circuits. Gasket is already kaput, probably corroded, hardened , badly compressed, not sealing combustion chamber well. Clean to an immaculate state both mating surfaces before replacing new head gasket. Change thermostat gasket as well. Torke head gasket to 30 NM (Newton Meter) following torquing sequence with a torque wrench.

Happy Boating

 

[Ken matlock]

I was afraid u were going to say that. Thanks for ur help. I was hoping maybe something with the thermostat or gasket May of been the problem but I figured it was the head gasket. Always good to get a second opinion. Thanks again for ur time and knowledge

 

[Sea Rider]

You are welcome, before tearing head gasket down, your last resource is : re torque head gasket back to specs, if the internal leak doesn't stop, go for a new head gasket. Don't know why boaters are afraid about replacing head gaskets, we do it all the time on all our Tohatsu outboards as a preventive maintenance procedure, avoid corrective ones specially in plain hot summer time.Take advantage to decarbon pistons heads and internal head area.

Happy Boating