Johnson 115, exhaust visible coming from head?

[russellcframe]

Hello,

I'm looking to possibly buy an old used boat. It has a Johnson 115 (which I believe is a '69). It has not run for a season. The owner received the boat from her husband in a divorce and doesn't know much about it. I ran the engine with ear muffs, it started fine and ran pretty well, shifting forward and reverse fine. I tested the compression and all 4 came out at 120.

I did notice that when we were running it there was a steady small puff of exhaust coming from the bottom of the cylinder/head (bottom right cylinder looking from behind the boat forward). I could not see exactly where it was coming from but I expect it was a blown head gasket. I believe it's fairly simple to repair if it is the head gasket, but I wanted to ask if there is any more serious potential problem here?

On an old motor like this I am expecting to decarb it with a SeaFoam treatment, rebuild carb, replace head gasket (if that's the problem above), new plugs and maybe wires, drain and fill lower unit, and take a look at the water pump and possibly replace impeller (unknown at this point).

Is there anything else I should be looking at, or concerned with right away?

Thank you for your assistance.

-Russ

 

[tashasdaddy]

Re: Johnson 115, exhaust visible coming from head?

compression say not the head gasket, maybe exhaust gasket or base gasket. did it have any problem running with the cowl on. that will tell you if there is an exhaust leak, as the do not like to breath exhaust. they will start to miss, and even die, due to lack of oxygen. replace impeller don't think about it.

read TOP SECRET FILE.

 

[R.Johnson]

Re: Johnson 115, exhaust visible coming from head?

You have an exhaust leak, period. That has to be fixed, no matter where it is coming from. If the leak is truly coming from the head, the gasket is blown from the combustion chamber, into the cooling passage, and then to the outside. I would pull the plug, and look for water beads. If you find the above, the head has to come off, which is no big chore.