1991 Johnson 150 cylinderhead sealant?

[cmax805]

I have a Johnson 150 faststrike J150GLEIS and I need to replace the seals on the cylinderhead for one side of my motor. The parts diagrams do not list a head gasket but rather o-rings for just the cylinder heads. The head still needs to be sealed to prevent water from leaking out of the cooling ports, but the seloc manual states "NEVER use automotive type head gasket sealer. The chemicals in the sealer will Cause electrolytic action and eat the aluminum faster than you can get to the bank for money to buy a new cylinder block." So what am I supposed to use to seal it?

 

[Faztbullet]

Black RTV

 

[cmax805]

Black RTV

Thanks for the reply. A guy in my local bass fishing group got back to me. Hopefully its just the cylinder ring/rtv thats causing low compression and not anything else like a hole in the top of the piston. I got the parts and rtv to fix if its just the ring/rtv. Starting on it now, wish me luck.

 

[racerone]

When head is off you will see why there is low compression.------And those SELOC manuals are best used in the wee house with the 1/4 moon in the door !!