59 Johnson leaky head gasket?

Hi again guys,<br /><br /> I have a 1959 Johnson seahorse 18HP.<br /> I lost alot of power 1 hour after buying it. Tried everything I know Carb's clean, Fuel filters clean, Points are new and adjusted correctly, Got good spark, have good compression, have good pressure in the gas tank, and have no leaks in the hoses, and have to ask for help.<br /> The bottom spark plug is always wet, idles good but will not get up to full speed. The bottom cylinar does not seem to be igniting the fuel because that cylinder is not running very hot. The top one on the other hand is. Could this be an indication of a leak and maybe some water is getting into the bottom cylinder causing it not to fire as it should.<br /> The motor did sit for 3 years before I bought it.<br /> Thanks for any input.

Re: 59 Johnson leaky head gasket?

It also had some bad gas but I've pretty much eliminated all fuel problems.

Re: 59 Johnson leaky head gasket?

try a new plug in the lower hole first it may be as simple as a dead plug. if that dont work run a compression test and give us the numbers

Re: 59 Johnson leaky head gasket?

Hi norman158,<br /><br /> I tried new plugs twice.<br />The bottom cylinder plug always gets wet.<br /> Did a compression test and the results were right around 100 lbs per cylinder.<br /> <br /><br /> Thanks for helping.

Re: 59 Johnson leaky head gasket?

Hi Itec<br /> Is your bottom plug wet with fuel? If it was wet from water it will look clean (like new).<br />My guess is you have a problem in the ignition for that hole. Better remove that coil and test. Look for shorts,maybe bad condencer,worn points. Swap coils, and see if the problem moves to the top hole. Something maybe rubbing. Unless that lower plug looks steam cleaned I don't think it's a head gasket.